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27 tirse ← ridjinme → nikle - ↑ Co ↓ Rh
tolsteci
cmene, sinxa, namcu	ridjinme, Co, 27
selratni porsi	binjinkle
girzu, dikni, dikni girzu	9, 4, d
viska selsimlu	mligusjinska sligu
teryratni	58.933195(5) g/mol
dutydikca kantu	[Ar] 3d7 4s2
dutydikca spisa terfendi nejni bo senta	2, 8, 15, 2
rarna ckaji
ganzu tcini	sligu
denmi to jibni kumke'o toi	8.90 g/cm³
selrunme	1768 K to 1495 °C toi
selfebvi	3200 K to 2927 °C toi
nalylikseltcini	le ? K .e le ? MPa
runme kelvo nejni	16.06 kJ/mol
febvi kelvo nejni	377 kJ/mol
gacyda'e
selratyte'i
krilisu'a	xavbliku
kijnentcini	2,3 jiljavslami joi kijno
ratni mijbi'ikoimre	135 pm
vricite'i
makpoi	barfu'imaksi
nengla greka'e	to 300 K toi 100 mW m-1K-1
snasutra	to le cinla garna .e le 293 K toi 4720 m/s
teryratni selcmi
djuno

ni'o lo ridjinme goi ko'a cu ratni li 27 li 58pi933195 fi'o sinxa la'o xy. Co xy. gi'e jdari rijblabi tirmaksi jinminra jinme

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

出典: フリー百科事典『ウィキペディア（Wikipedia）』

鉄 - コバルト - ニッケル Co Rh
一般特性
名称, 記号, 番号	コバルト, Co, 27
分類	遷移金属
族, 周期, ブロック	9（VIII）, 4 , d
密度, 硬度	8900 kg/m3, 5.0
色	光沢ある灰色
原子特性
原子量	58.933195 amu
原子半径（計測値）	135（152）pm
共有結合半径	126 pm
VDW半径	n/a pm
電子配置	[Ar]3d74s2
電子殻	2, 8, 15, 2
酸化数（酸化物）	2, 3（両性酸化物）
結晶構造	六方最密構造
物理特性
相	固体（強磁性）
融点	1768 K（1495 ℃）
沸点	3200 K（2927 ℃）
モル体積	6.67 ×10-3 m3/mol
気化熱	376.5 kJ/mol
融解熱	16.19 kJ/mol
蒸気圧	175 Pa（1768 K）
音の伝わる速さ	4720 m/s（293.15 K）
その他
クラーク数	0.004 %
電気陰性度	1.88（ポーリング）
比熱容量	420 J/（kg*K）
導電率	17.2 106/m Ω
熱伝導率	100 W/（m*K）
第1イオン化エネルギー	760.4 kJ/mol
第2イオン化エネルギー	1648 kJ/mol
第3イオン化エネルギー	3232 kJ/mol
第4イオン化エネルギー	4950 kJ/mol
（比較的）安定同位体
同位体 NA 半減期 DM DE MeV DP 56Co {syn.} 77.27 日 ε 4.566 56Fe 57Co {syn.} 271.79 日 ε 0.836 57Fe 58Co {syn.} 70.86 日 ε 2.307 58Fe 59Co 100% 中性子32個で安定 60Co {syn.} 5.2714 年 β- 2.824 60Ni
注記がない限り国際単位系使用及び標準状態下。

コバルト（Cobalt）は、原子番号 27 の元素。元素記号は Co。鉄族元素の一つ。安定な結晶構造は六方最密充填構造 (hcp) で、強磁性体。純粋なものは銀白色の金属である。722K以上で面心立方構造 (fcc) に転移する。

鉄より酸化されにくく、酸やアルカリにも強い。

[編集] 歴史

1737年 、ゲオルグ・ブラント（Georg Brandt、スウェーデン）により発見。コバルトという名称と元素記号は、ドイツ語で地の妖精を意味するコーボルト（Koboldまたはkobalt）に由来する。コバルト鉱物は冶金が困難なため、16世紀頃のドイツでは、コーボルトが坑夫を困らせる為に魔法をかけたものとされていた。

[編集] 用途

単体金属としてのコバルトの用途はほとんどないが、その中で最も重要なものは、放射性同位体のコバルト60をγ線源として用いるもので、医療分野での放射線療法、ガンマ線滅菌、食品分野での食品照射（ジャガイモの発芽防止）などに広く利用されている。

コバルトが不純物（ケイ酸コバルト）として入ることによって、ガラスなどが青色を呈する。青色の顔料であるコバルトブルーはアルミン酸コバルトを主成分としており、陶磁器の着色や絵具などに用いられている。他にも亜鉛とコバルトの複合酸化物は、コバルトグリーンと呼ばれる緑色の顔料になるなど、冷色系の顔料の原料として重要である。暖色系でも亜硝酸第二コバルトカリはコバルトイエローと呼ばれる黄色の顔料となり、オーレオリンの名前で絵具として使われる。

化合物の塩化コバルト(II) は、シリカゲルに混ぜ、湿気の吸収具合を色の変化で示す指示薬として使われる。

また、コバルトは、主に合金として重要であり工業的に利用される。初期のコバルト合金はそれまでの、高速度工具鋼にコバルトを添加した超高速度工具鋼に用いられたほか、切断工具材料としてそれまでの合金に添加されることで、コバルトの需要は増していった。現在、ニッケル・クロム・モリブデン・タングステン、あるいはタンタルやニオブを添加したコバルト合金は高温でも磨耗しにくく、腐食にも強いため、ガスタービンやジェットエンジンといった、高温で高い負荷が生ずる装置などに用いられているほか、溶鉱炉や石油化学コンビナートなどでも十分に役割を果たす。またステライトに代表されるコバルト・クロム・タングステン（あるいはモリブデン）・炭素を使った4元系の合金は、磨耗に強く表面強化が必要とされた工業分野において幅広く利用され始めている。この合金は、鋳型として使用するほか、粉末として吹き付けることや溶射して利用することも可能であり、利用技術の発達によって、航空機の表面にコーディングすることなどをはじめ、広い分野で実用化が始まっている。コバルト-モリブデン-ケイ素合金は、耐摩耗性を有し摩擦係数が小さい（滑らかな）性質を示し、ベアリングの特徴を併せ持つなどなど有用な特性を持った合金も開発されている。またコバルト-クロム-モリブデン合金とコバルト-クロム-タングステン-ニッケル合金は腐食しにくいため歯科医療や外科手術などでも使われている。近年では飛躍的に進歩したものとして、ニッケル-コバルト-モリブデン鋼の大幅な特性向上があげられる。非常に強い強度と高い靭性を持ったこの合金は、多くの分野での応用が期待されており研究が進んでいる。

加えてコバルト合金は他にも磁気材料として鉄とともに最も重要な役割を果たしてきた。コバルトを添加することにより、磁性やキュリー値が上昇するなど磁気材料としての性能が高まる。コバルトを使った合金のひとつであるアルニコ合金はかつては最も幅広く用いられていた永久磁気材料であった。サマリウムコバルト磁石はコバルトとサマリウムの金属間化合物で、強い保持力がある。

また人体にとって、コバルトは微量ながら必須の元素である。ビタミンB12に含まれている。

この金属は、日本国内において産業上重要性が高いものの地殻存在度が低く供給構造が脆弱である。日本では国内で消費する鉱物資源の多くを他国からの輸入で支えている実情から、万一の国際情勢の急変に対する安全保障策として国内消費量の最低60日分を国家備蓄すると定められている。

[編集] コバルト爆弾

核爆弾の一種で、原子爆弾又は水素爆弾の まわりをコバルトで包んだもの。具体的には、核反応が充分に進行しないうちに核物質が四散して爆発が不完全に終わるのを防ぐ「タンパー」と呼ばれる重金属 の覆いにコバルトを用いる。コバルトの原子量は59であるが、核反応により放出される中性子を取り込んでコバルト60が生成され、これが爆弾の爆発と共に 広範囲にまき散らされる。コバルト60は半減期5.3年でガンマ線を放射するため、コバルト爆弾は放射線兵器となる。中性子爆弾と共にSFの第三次世界大戦など核戦争による世界破滅するジャンルでよく使用想定されていたが、中性子爆弾と違って、コバルト爆弾では半減期の長いコバルト60による汚染のため味方にも被害が及び、被災地の占領も困難であるなどの理由で実用性に乏しく、理論上の兵器に終わった。

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

Úr Wikipediu, frjálsa alfræðiritinu

Járn	Kóbolt	Nikkel
	Ródín
Útlit Efnatákn Co Sætistala 27 Efnaflokkur Hliðarmálmur Eðlismassi 8900,0 kg/m³ Harka 5,0 Atómmassi 58,9332 g/mól Bræðslumark 1768,0 K Suðumark 3000,0 K Efnisástand (við staðalaðstæður) Fast form Lotukerfið

Kóbolt er frumefni með efnatáknið Co og er númer 27 í lotukerfinu.

[breyta] Almennir eiginleikar

Kóbolt er hart, silfurhvítt járnsegulefni. Það er oft tengt nikkel og bæði efnin einkenna loftsteinajárn. Spendýr þarfnast smárra skammta af Kóboltsöltum til að lifa. Kóbolt-60, sem er geislavirk samsæta þess, er mikilvægt sporefni og var notað við geislameðferð krabbameins. Kóbolt hefur tvo þriðju segulleiðni járns.

Algeng oxunarstig kóbolts eru +2 og +3 og jafnvel +1.

[breyta] Notkun

• Í málmblöndur
  • Í ýmsa hluta þotuhreyfla.
  • Tæringar- og slitþolnar málmblöndur.
  • Háhraðastál.
  • Steypta karbíða og demantatól.
• Í segulstál og segulmagnaða upptökumiðla:
  • Alnico segulstál.
• Sem hvati í olíu- og efnaiðnaði.
• Í rafhúðun sökum útlits, hörku og oxunarviðnáms.
• Sem þerringarefni í málningu, lakk og blek.
• Sem undirlag fyrir glerung á postulíni.
• Litarefni (kóboltblár og kóboltgrænn).
• Rafskaut rafhlaðna.
• Styrking í dekk.
• Kóbolt-60 hefur mörg not sem uppspretta gammageislunar
  • Við geislalækningar.
  • Við dauðhreinsun.
  • Það er notað í gegnumlýsingu í iðnaði til að finna samsetningargalla í málmhlutum.

Co-60 er nytsamlegt sem uppspretta gammageisla að hluta til því að það getur verið framleitt í þekktum stærðum og í mjög stórum stíl með því að láta nifteindir dynja á náttúrulegu Kóbolti í kjarnaofni í ákveðinn tíma.

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

Kobal adalah suatu unsur kimia dalam tabel periodik yang memiliki lambang Co dan nomor atom 27.

Warna: sedikit berkilauan, metalik, keabu-abuan Penggolongan: Metalik Ketersediaan: unsur kimia kobal tersedia di dalam banyak formulasi yang mencakup kertas perak, potongan, bedak, tangkai, dan kawat. contoh besar Dan kecil unsur kimia. Unsur kimia kobalt juga merupakan suatu unsure dengan sifat rapuh agak kerasdan mengandung metal serta kaya sifat magnetis yang serupa setrika. Unsur kimia kobalt adalah batu bintang. Deposit bijih. Cobalt-60 ( 60Co) adalah suatu isotop yang diproduksi menggunakan suatu sumber sinar ( radiasi energi tinggi). unsur kimia/kobalt mewarnai gelas/kaca serta memiliki suatu keindahan warna kebiruan.

Secara umum dapat kita deskripsikan sebagai berikut :

• Nama: unsur kimia kobal • Lambang: Co • Nomor-Atom: 27 • Berat atom: 58.933200 ( 9) • Golongkan nomor;jumlah: 9 • Nomor periode;Jumlah: 4

Salah satu makanan yang kita konsumsi ber sumber vitamin B12 yang merupakan suatu campuran yang berisi unsur kobalt, adalah marmite, tetapi unsure yang dikandung didalamnya tergolong unsur lebih lemah dan lembut. Di Australia dikenal dengan Vegemite, sedangkan di Amerika, Marmite dicampur dengan pindakas.

Banyak bijih berisi unsur kimia kobalt, tetapi tidak memiliki arti penting untuk ekonomi. meliputi sulfid dan arsenides linnaeite, Co3S4, kobaltit, Coass, dan smaltite, Coas2. Digunakan untuk industri, secara normal diproduksi sebagai byproduct dari produstion tembaga, nikel Bijih yang dibakar Secara normal membentuk suatu campuran oksida metal. Perawatan dengan cuka sulphuric dapat meninggalkan tembaga metalik sebagai residu dan disolves. Besi diperoleh oleh hujan, timbulnya dengan lima kapur perekat ( Cao) sedang unsur kimia/kobalt diproduksi ketika hidroksida hujan hujan akantimbul hipoklorit sodium ( Naocl) 2Co2+(aq) + NaOCl(aq) + 4OH-(aq) + H2O 2Co(OH)3(s) + NaCl(aq)

Trihydroxide Co(OH)3 dipanaskan untuk membentuk oksida dan kemudian dikurangi dengan karbon akan untuk membentuk unsur kimia/kobalt metal. 2Co(OH)3 (heat) Co2O3 + 3H2O 2Co2O3 + 3C Co + 3CO2 berikut Penggunaan untuk unsur kobalt : 1. Dapat dicampur dengan besi, nikel dan batang-batang rel lain untuk membuat Alnico, suatu campuran logam memiliki kekuatan magnetis yang banyak digunakan mesin jet dan turbin gas mesin/motor. 2. Digunakan sebagai bahan baja tahan-karat dan baja magnit. 3. Digunakan di dalam campuran logamuntuk turbin gas generator dan turbin pancaran 4. Digunakan di dalam menyepuh listrik oleh karena penampilannya, kekerasan, dan perlawanan ke oksidasi 5. Digunakan untuk produksi warna biru permanen dan brilian untuk porselin, gelas/kaca, serta barang tembikar, pekerjaan ubin, dan email 6. Cobalt-60, merupakan artifical isotop, dimana sebagai suatu sumber sinar penting, dan secara ekstensif digunakan sebagai suatu pengusut serta agen radiotherapeutic. Sumber 60Co yang Ringkas dan mudah. 7. Digunakan sebagai campuran pigmen cat

Senyawa biner : beberapa senyawa biner dengan halogen yang dikenal sebagai halides, oksigen dan hidrogen yang dikenal sebagai hydrides. Bagian ini Webelements akan diperluas di masa datang. Karena masing-masing campuran, yang didasarkan jumlah oksidasi, suatu bentuk wujud elektronik.. juga diberi campuran yang lebih eksotis. Istilah hydride digunakan di dalam suatu pengertian umum untuk menandai adanya campuran dan tidak harus menunjukkan campuran yang didaftar secara kimiawi. Di dalam campuran unsur kimia kobalt dikenal angka-angka oksidasi unsur kimia yang paling umum adalah: 3, dan 2.

Hydrides Istilah hydride digunakan untuk menandai adanya campuran secara kimiawi.

Fluorides • CoF2: cobalt (II) fluoride

unsur kimia/kobalt ( II) fluoride " Rumusan [sebagai/ketika] biasanya [di]tertulis: Cof2 " sistem bukit Rumusan: Co1F2 " CAS nomor;jumlah pencatatan: [ 10026-17-2] " Rumusan menimbang: 96.93 " Kelas: fluoride

Sinonim

" unsur kimia/kobalt ( II) fluoride " unsur kimia/kobalt difluoride " unsur kimia/kobalt fluoride Sifat fisis " Warna: merah muda " Penampilan: padat dari kristal/jernih " Titik-Lebur: 1200°C " Mendidih titik: 1400°C " Kepadatan: 4460 kg m-3

unsur angka-angka oksidasi dan Analisa
Karena masing-masing campuran, dan [di mana/jika] mungkin, suatu nomor;jumlah oksidasi formal untuk masing-masing unsur diberi, hanyalah  kegunaan nomor;jumlah ini terbatas, terutama sangat untuk p-block unsur-unsur khususnya. yang didasarkan Yang nomor;jumlah oksidasi, suatu bentuk wujud elektronik adalah juga diberi tetapi catatan yang untuk campuran [yang] lebih eksotis [yang] kamu perlu memandang ini sebagai pemandu [yang] saja.

Element % Oksidasi formal bentuk wujud Elektronik formal Co 60.80 2 [Ar].3d7 F 39.20 -1 [He].2s2.2p6 Sintese

Tidak tersedia
status padat Struktur

" Ilmu ukur unsur kimia/kobalt: " Prototypical struktur:

Isotop mempola

Apa [yang]  mengikuti menjadi isotop yang dihitung mempola untuk Cof2 unit dengan ion [yang] yang paling keras mulai 100%.
Rumusan: Co1F2

Chlorides • CoCl2: cobalt (II) chloride Campuran unsur kimia/kobalt:

unsur kimia/kobalt ( II) klorid

" Rumusan [sebagai/ketika] biasanya [di]tertulis: Cocl2 " sistem bukit Rumusan: Cl2Co1 " CAS nomor;jumlah pencatatan: [ 7646-79-9] " Rumusan menimbang: 129.839 " Kelas: klorid Sinonim " unsur kimia/kobalt ( II) klorid " unsur kimia/kobalt klorid " unsur kimia/kobalt dichloride

Sifat fisis

" Warna: biru " Penampilan: padat dari kristal/jernih " Titik-Lebur: 724°C; 735°C " Mendidih titik: 1049°C " Kepadatan: 3360 kg m-3 unsur angka-angka oksidasi dan Analisa

Karena masing-masing campuran, dan [di mana/jika] mungkin, suatu nomor;jumlah oksidasi formal untuk masing-masing unsur diberi, hanyalah  kegunaan nomor;jumlah ini terbatas, terutama sangat untuk p-block unsur-unsur khususnya. yang didasarkan Yang nomor;jumlah oksidasi, suatu bentuk wujud elektronik adalah juga diberi tetapi catatan yang untuk campuran [yang] lebih eksotis [yang] kamu perlu memandang ini sebagai pemandu [yang] saja

Element % Oksidasi formal menyatakan bentuk wujud Elektronik formal Cl 54.61 -1 [Ne].3s2.3p6 Co 45.39 2 [Ar].3d7 Co 45.39 2 [ Ar].3D7

Sintese
Tidak tersedia
status padat Struktur

" Ilmu ukur unsur kimia/kobalt: " Prototypical struktur: Cdcl2

Isotop mempola

Apa [yang]  mengikuti menjadi isotop yang dihitung mempola untuk Cocl2 unit dengan ion [yang] yang paling keras mulai 100%.
Rumusan: Co1Cl2

Campuran unsur kimia/kobalt:

unsur kimia/kobalt ( II) bromida/hal umum

" Rumusan [sebagai/ketika] biasanya [di]tertulis: Cobr2 " sistem bukit Rumusan: Br2Co1 " CAS nomor;jumlah pencatatan: [ 7789-43-7] " Rumusan menimbang: 218.741 " Kelas: bromida/hal umum Sinonim " kimia/kobalt unsur( II) bromida/hal umum " unsur kimia/kobalt bromida/hal umum " kimia/kobalt unsur dibromide

Sifat fisis

" Warna: hijau " Penampilan: crytalline padat " Titik-Lebur: 678°C " Mendidih titik: " Kepadatan: 4900 kg m-3 unsur angka-angka oksidasi dan Analisa

Karena masing-masing campuran, dan [di mana/jika] mungkin, suatu nomor;jumlah oksidasi formal untuk masing-masing unsur diberi, hanyalah  kegunaan nomor;jumlah ini terbatas, terutama sangat untuk p-block unsur-unsur khususnya. yang didasarkan Yang nomor;jumlah oksidasi, suatu bentuk wujud elektronik adalah juga diberi tetapi catatan yang untuk campuran [yang] lebih eksotis [yang] kamu perlu memandang ini sebagai pemandu [yang] saja

Element % Oksidasi formal bentuk wujud Elektronik formal Br 73.06 -1 [Ar].3d10.4s2.4p6 Co 26.94 2 [Ar].3d7 Co 26.94 2 [ Ar].3D7

Sintese
Tidak tersedia
status padat Struktur

" Ilmu ukur unsur kimia/kobalt: " Prototypical struktur: Cdi2

Isotop mempola

Apa [yang]  mengikuti menjadi isotop yang dihitung mempola untuk Cobr2 unit dengan ion [yang] yang paling keras mulai 100%

Campuran unsur kimia/kobalt:

unsur kimia/kobalt ( II) iodid

" Rumusan [sebagai/ketika] biasanya [di]tertulis: Coi2 " sistem bukit Rumusan: Co1I2 " CAS nomor;jumlah pencatatan: [ 15238-00-3] " Rumusan menimbang: 312.742 " Kelas: iodid

Sinonim

" unsur kimia/kobalt ( II) iodid " unsur kimia/kobalt diiodide " unsur kimia/kobalt diiodide(, hitam) " unsur kimia/kobalt iodid " unsur kimia/kobalt iodid(, hitam) " unsur kimia/kobalt iodid(, hitam) Sifat fisis " Warna: blue-black " Penampilan: padat dari kristal/jernih " Titik-Lebur: 515°C (( di (dalam) vacuo)) " Mendidih titik: " Kepadatan: 5600 kg m-3

unsur angka-angka oksidasi dan Analisa
Karena masing-masing campuran, dan [di mana/jika] mungkin, suatu nomor;jumlah oksidasi formal untuk masing-masing unsur diberi, hanyalah  kegunaan nomor;jumlah ini terbatas, terutama sangat untuk p-block unsur-unsur khususnya. yang didasarkan Yang nomor;jumlah oksidasi, suatu bentuk wujud elektronik adalah juga diberi tetapi catatan yang untuk campuran [yang] lebih eksotis [yang] kamu perlu memandang ini sebagai pemandu [yang] saja

Element % Oksidasi formal bentuk wujud Elektronik formal Co 18.84 2 [Ar].3d7 I 81.16 -1 [Kr].4d10.5s2.5p6

Sintese

Tidak tersedia
status padat Struktur

" Ilmu ukur unsur kimia/kobalt: " Prototypical struktur:

Campuran unsur kimia/kobalt:

unsur kimia/kobalt ( II) oksida

" Rumusan [sebagai/ketika] biasanya [di]tertulis: Suara dengkur " sistem bukit Rumusan: Co1O1 " CAS nomor;jumlah pencatatan: [ 1307-96-6] " Rumusan menimbang: 74.933 " Kelas: oksida Sinonim " unsur kimia/kobalt ( II) oksida " unsur kimia/kobalt oksida

Sifat fisis

" Warna: abu-abu atau buah zaitun hijau " Penampilan: padat dari kristal/jernih " Titik-Lebur: 1830°C " Mendidih titik: " Kepadatan: 6400 kg m-3 unsur angka-angka oksidasi dan Analisa

Karena masing-masing campuran, dan [di mana/jika] mungkin, suatu nomor;jumlah oksidasi formal untuk masing-masing unsur diberi, hanyalah  kegunaan nomor;jumlah ini terbatas, terutama sangat untuk p-block unsur-unsur khususnya. yang didasarkan Yang nomor;jumlah oksidasi, suatu bentuk wujud elektronik adalah juga diberi tetapi catatan yang untuk campuran [yang] lebih eksotis [yang] kamu perlu memandang ini sebagai pemandu [yang] saja

Element % Oksidasi formal bentuk wujud Elektronik formal Co 78.65 2 [Ar].3d7 O 21.35 -2 [He].2s2.2p6 Sintese

Tidak tersedia
status padat Struktur

" Ilmu ukur unsur kimia/kobalt: " Prototypical struktur: Nacl ( garam-batuan)

Isotop mempola

Apa [yang]  mengikuti menjadi isotop yang dihitung mempola untuk suara dengkur Unit dengan ion [yang] yang paling keras mulai 100%.
Rumusan: Co1O1

Campuran unsur kimia/kobalt:

unsur kimia/kobalt ( II) sulfid

" Rumusan [sebagai/ketika] biasanya [di]tertulis: Cos " sistem bukit Rumusan: Co1S1 " CAS nomor;jumlah pencatatan: [ 1317-42-6] " Rumusan menimbang: 90.999 " Kelas: sulfid

Sinonim

" unsur kimia/kobalt ( II) sulfid " unsur kimia/kobalt sulfide

Sifat fisis " Warna: hitam " Penampilan: bedak " Titik-Lebur: 1182°C " Mendidih titik: " Kepadatan: 5450 kg m-3

unsur angka-angka oksidasi dan Analisa

Karena masing-masing campuran, dan [di mana/jika] mungkin, suatu nomor;jumlah oksidasi formal untuk masing-masing unsur diberi, hanyalah  kegunaan nomor;jumlah ini terbatas, terutama sangat untuk p-block unsur-unsur khususnya. yang didasarkan Yang nomor;jumlah oksidasi, suatu bentuk wujud elektronik adalah juga diberi tetapi catatan yang untuk campuran [yang] lebih eksotis [yang] kamu perlu memandang ini sebagai pemandu [yang] saja

Element % Formal oxidation state Formal electronic configuration Co 64.76 2 [Ar].3d7 S 35.24 -2 [Ne].3s2.3p6 Sintese

Tidak tersedia
status padat Struktur

" Ilmu ukur unsur kimia/kobalt: " Prototypical struktur:

Isotop mempola

Apa [yang]  mengikuti menjadi isotop yang dihitung mempola untuk Cos unit dengan ion [yang] yang paling keras mulai 100%.
Rumusan: Co1S1

Campuran unsur kimia/kobalt:

unsur kimia/kobalt ( II) telluride

" Rumusan [sebagai/ketika] biasanya [di]tertulis: Kandang kecil untuk ternak " sistem bukit Rumusan: Co1Te1 " CAS nomor;jumlah pencatatan: [ 12017-13-9] " Rumusan menimbang: 186.533 " Kelas: telluride

Sinonim

" unsur kimia/kobalt ( II) telluride " unsur kimia/kobalt telluride Sifat fisis " Warna: " Penampilan: padat dari kristal/jernih " Titik-Lebur: " Mendidih titik: " Kepadatan: 8800 kg m-3 [yang] kira-kira

unsur angka-angka oksidasi dan Analisa
Karena masing-masing campuran, dan [di mana/jika] mungkin, suatu nomor;jumlah oksidasi formal untuk masing-masing unsur diberi, hanyalah  kegunaan nomor;jumlah ini terbatas, terutama sangat untuk p-block unsur-unsur khususnya. yang didasarkan Yang nomor;jumlah oksidasi, suatu bentuk wujud elektronik adalah juga diberi tetapi catatan yang untuk campuran [yang] lebih eksotis [yang] kamu perlu memandang ini sebagai pemandu [yang] saja

Element % Formal oxidation state Formal electronic configuration Co 31.59 2 [Ar].3d7 Te 68.41 -2 [Kr].4d10.5s2.5p6 Sintese

Tidak tersedia
Isotop mempola
Apa [yang]  mengikuti menjadi isotop yang dihitung mempola untuk kandang kecil untuk ternak Unit dengan ion [yang] yang paling keras mulai 100%.
Rumusan: Co1Te1

Chlorides • CoCl2: cobalt (II) chloride Bromides • CoBr2: cobalt (II) bromide Iodides • CoI2: cobalt (II) iodide Oxides • CoO: cobalt (II) oxide

Sulfides • CoS: cobalt (II) sulphide Tellurides • CoTe: cobalt (II) telluride

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

ניקל - קובלט - ברזל Co Rh
כללי
מספר אטומי	27
סמל כימי	Co
סדרה כימית	מתכות מעבר
צפיפות	8900 kg/m3
מראה	מתכתי עם גוון אפור
תכונות אטומיות
משקל אטומי	58.933200 amu
רדיוס ואן דר ולס	____ pm
סידור אלקטרונים ברמות אנרגיה	2, 8, 15, 2
תכונות פיזיקליות
מצב צבירה בטמפ' החדר	מוצק
טמפרטורת התכה	1,490°C
טמפרטורת רתיחה	2,930°C
לחץ אדים	175Pa ב 1768°K
מהירות הקול	4720 מטר לשנייה ב293.15°K
שונות
אלקטרושליליות	1.88
קיבול חום סגולי	420 J/(kg·K)
מוליכות חשמלית	17.2 106/m·Ω
מוליכות תרמית	100 W/(m·K)
אנרגיית יינון ראשונה	760.4 kJ/mol

קובלט (cobalt) הוא יסוד כימי שסימלו Co ומספרו האטומי 27.

[עריכה] תכונות

קובלט הוא מתכת חזקה, בצבע לבן כסוף ופרומגנטית. קובלט וניקל הם חומרים אופיינים למטאורים. קובלט מתכתי מכיל תערובת של שתי צורות קריסטלוגרפיות, hcp וfcc.

דרגות החימצון של קובלט הן 2+ ו3+. הדרגה 1+ קיימת לעתים נדירות.

[עריכה] שימושים

לקובלט מספר שימושים, הנה חלק מהם:

• • נייר הספוג ביוני קובלט (נייר קובלט) הינו אִינדיקטור המזהה נוכחות מים.
• בסגסוגות:
  • ייצור סגסוגות-על (שיכולות לעמוד בלחץ וטמפרטורה גבוהים מאוד) שאיתן בונים מנועים למטוסים.
  • שילוב קובלט בסגסוגות מגביר עמידות לקורוזיה ושחיקה.
  • חיזוק קרבידים וכלים אחרים.
• ייצור מגנטים אמצעי אחסון מגנטיים.
  • מגנטי "אלניקו" - סגסוגת קובלט ברזל, ניקל, אלומיניום ונחושת.
• לקובלט תפקיד כזרז בתעשיית הנפט והכימיקלים.
• בציפוי מתכות באלקטרוליזה, בזכות הקשיחות ועמידות לקורוזיה.
• פיגמנטים בצבעים כחול וירוק.
• קובלט הוא אחד ממרכיבי סוללות.
• קובלט-60 הוא מקור לקרינת גמא מכיוון שקל ונוח להפיק אותו בכמויות גדולות.
  • לקובלט-60 שימוש ברדיותרפיה.
  • סטריליזציה של מזון ("פסטור קר").

[עריכה] שימושים ברפואה

קובלט-60 הוא מתכת רדיואקטיבית שמשתמשים בה לעתים קרובות ברדיותרפיה. אחד החסרונות בשימוש בקובלט-60 הוא העובדה ששימוש בו מפזר אבק מתכתי שיכול לגרום לבעיות בהגנה נגד קרינה. המקור לקובלט-60 שימושי ל־5 שנים, למרות שהוא ממשיך להקרין גם אחרי זמן זה. המכונה הראשונה שנבנתה לטיפול בעזרת קובלט-60 הוקמה בקנדה.

[עריכה] היסטוריה

תרכובות קובלט ידועות עוד מימי קדם, ששימשו לצביעת זכוכית בצבע כחול. האדם שגילה את הקובלט הוא ג'ורג' ברנדט התאריך המדויק אינו ידוע, אבל משוער שזה קרה בין השנים 1730 ל-1737. ג'ורג' הוכיח שמקור הצבע הכחול בזכוכית הוא מקובלט ולא מביסמוט (שנמצא לעתים קרובות עם קובלט).

במשך המאה ה-19, בין 70%-80% מהקובלט בעולם הופק בנורבגיה.

ב-1938, ג'ואן ליוינגוד וגלן סיבורג גילו את האיזוטופ קובלט-60.

מקור השם הוא במלה הגרמנית Kobold שמשמעותה "שדון" או "רוח זדונית". כורים היו מכנים את הקובלט כך מכיוון שלעתים קרובות היה מרעיל אותם.

[עריכה] תפקיד ביולוגי

בכמויות קטנות קובלט חיוני להרבה יצורים חיים, כולל בני אדם. כמויות מזעריות של קובלט באדמה משפרות את הבריאות של חיות מרעה. קובלט היא אחד ממרכיבי ויטמין B12.

[עריכה] צורה בטבע

קובלט לא נמצא בטבע בצורתו המתכתית והוא נכרה במכרות ומופק מעופרותיו. המחצבים העיקריים הם קובלטיט (Cobaltite), אריתריט (Erythrite), גלאוקודוט (Glaucodt) וסקאטרודיט (Skutterudite). המדינות המובילות בייצור קובלט בעולם הן זמביה, רוסיה, סין ואוסטרליה.

[עריכה] אמצעי זהירות

תרכובות קובלט מצריכות טיפול מיוחד מכיוון שהן רעילות. חשיפה לקובלט-60 יכולה לגרום לסרטן, אכילת קובלט-60 מסוכנת עוד יותר, מכיוון שבמקרה זה הקובלט יכנס לתוך רקמות וישתחרר באיטיות. בנשק גרעיני לעתים מעשירים את המעטפת בקובלט-60 וכך יוצרים מקור קרינה נוסף.

[עריכה] קישורים חיצוניים

• קובלט ב־Webelements (אנגלית)

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

一、精密磨削和超精密磨削

随着技术创新与高科技产品的不断涌现，零件的加工精度和表面完整性要求愈来愈高。例如，广泛用于液压随动系统中精密偶件的阀芯与阀套的配合精度常要求达到 μm级，录像头、影碟机等精密零件的加工精度已提高到0.1μm，激光陀螺平面反射镜的平面度误差要求小于0.05μmRa<0.001μm。目前 作为传统精密加工方法的磨削正在向超精密磨削、超精密研磨和抛光等方向发展。精密和超精密磨削的关键是最后一道工序，要从工件表面降去一层小于或等于工件 最后精度等级的表面层。因此，要实现精密或超精密磨削，首先要减少磨粒单刃切除量，而使用微细或超微细微粉的磨粒是减少单刃切除量的最有效途径。日本镜面 磨削时使用的磨具粒度为4000~8000#，其微粉的平均尺寸为1.5μm~4μm，加工后工件表面粗糙度可达Ra0.003μm~0.005μm。使 用粒径为20nm的SiO2超微细微粉及锡抛光盘对蓝宝石单晶进行无损超精密研磨的抛光，可获得Ra＜1nm的表面。目前精密量块、光学平晶、集成电路的 硅基片等精密零件都是采用上述方法来获得高质量的表面。为使研磨压力均匀可控，近几年来还开发了磁力研磨，磁流体超精研磨及弹性发射加工（EEM）等新技 术。

实现超精密磨削是一项系统工程，包括研制高速高精度的磨床主轴、导轨与微进给机构，精密的磨具及其平衡与修整技术，以及磨削环境的净化与冷却方式等。我国 郑州磨产磨具磨削研究所开发的喷涂陶瓷精密磨削工艺，其尺寸精度和加工表面粗糙度均与国外水平相当，磨削效率高于国外一倍左右。该工艺在张家口石油机械 厂、武汉青山热电厂等单位使用后，取得了显著的经济效益。

二、开发了SG和ABN800等磨料新品种

SG磨料是美国Norton公司首先推出的。它是由亚微米级的Al2O3晶体，采用溶胶凝胶（Sol-gel）工艺合成并经烧结制成的新型陶瓷刚玉磨料。 与普通电熔刚玉磨料相比，不但硬度高，而且因磨粒是微晶结构，它有很多晶解面，在外力作用下或在修锐和修整中仅微晶脱落，不断产生锋利的切削刃，自锐性 好，且剥落较少，用其制作的磨具具有耐磨性好、磨削热少，使用寿命长、磨削比（磨除材料体积与磨具消耗体积之比）大、切除率高和磨削质量好等优点，现已广 泛用于航空航天、汽车、轴承、工模具、仪器仪表等领域的精磨与成形磨削等方面的加工。目前常用的是SG与WA（白刚玉）或A（棕刚玉）的混合磨料，其中 SG所占比例有100%、50%、30%、20%、10%等多种，分别用SG、SG5、SG3、SG2、SG1来表示。国外一些性能优异的磨具制品，如德 国Hermes磨料公司的CB宝石蓝砂轮、奥地利Tyrolit公司开发的CSS砂轮、美国Cincinnati Milacron公司生产的MSB砂轮、日本Noritake株式会社推出的新型CX陶瓷砂轮，都是类似SG磨料的微晶烧结刚玉的产品。

在激烈的市场竞争中，近年来美国Norton公司又推出了SG磨料的第二代产品——TG（Targa）磨料。它保留了SG的优点，在磨料形状上作了新的突 破，很有细的棒状晶态结构，适用于缓进给磨削及加工铬镍铁合金、高温合金等难加工材料。据称，TG磨料的材料切除率为刚玉的2倍，寿命为刚玉的7倍。

SG磨料的磨削性能介于刚玉与CBN（立方氮化硼）之间，价格适中，是一种很有应用前景的磨料新品种。新型SG磨料我国亦已开发成功，第七砂轮集团公司已在进行该磨料的工业性应用。

ABN800和ABN600是De Beers公司开发的CBN磨料新品种。其磨粒均是微晶结构，具有较高的抗压强度和热稳定性。其中ABN800有更独特的晶体特性，磨料在受力破碎时无论 大小都具有尖角，使其在使用过程中能始终保持锋利的磨削性能，因而磨削时产生的磨削力小，功率消耗少，加工质量好，使用寿命长。近几年来在国际展览会上， 国外展出的一些CBN磨具大多是ABN800和ABN600的微晶CBN磨料制品。

三、高效率磨削

高简编和高精度是现代制造技术追求的两大目标。大家知道，磨削虽然在达到的加工精度和表面粗糙度方面具有无可比拟的优势，但其材料切除率Q（单位时产内磨 除材料的体积，mm3/s）难以与其他切削抗衡。这是因为Q等于磨屑平均断面积、磨屑平均长度和单位时间内的作用磨粒数（磨屑数）三者的乘积。所以，为了 提高磨削效率，必须采用增大单位时间内作用的磨粒数（如高速磨削、超高速磨削、砂带磨削等）、增大磨屑平均断面积（如各种重磨削）及增大磨屑平均长度（如 缓进给深磨、立轴平磨）等许多高效率磨削技术。其中重负荷荒磨、超高速磨削、砂带磨削和高效深磨技术的发展尤为引人注目。

重磨削的发展，使磨削不仅适用于精密加工和超精密加工，而且也适用于粗加工与荒加工。

高速磨削是指磨削速度vc为50m/s~150m/s的磨削，而vc＞150m/s的磨削称为超高速磨削。近年来研究表明，超高速磨削不但可大幅度提高工 效、延长磨具寿命用降低表面粗糙度，而且可对硬脆材料实现延性磨削，对高塑性材料和难磨材料也有良好的磨削效果。过去由于受磨具回转破裂速度的限制，以及 磨削温度高和工件表面烧伤的制约，磨削速度长期停滞在80m/s左右。随着CBN磨料的使用和高速磨削机理研究的深入，现在工业上实用的磨削速度已达到了 150m/s~250m/s，实验室中达到500m/s。超高速磨削需要有超高速磨削磨具、超高速磨床、磨削液及其供液过滤系统以及对磨削过程监控等相关 技术作支撑。在IMTS98，Toyota Machinery USA展出的高速磨床，磨50HRC淬硬钢的传动轴，砂轮线速度达120m/s；展出的凸轮磨床，砂轮线速度为200m/s。我国在国家自然科学基金资助 下，已建造了200m/s的超高速磨削试验台，并开展了对超高速磨削机理的系统研究。

砂带磨削的加工效率比普通磨削高5~10倍以上。由于它属于弹性磨削，有利于解决磨削烧伤和工作变形等问题。所以，工业发达国家的砂带磨削已占总磨削量的 一半左右。近几年来国外的砂带已用Cubitron（美国3M公司）和SG磨料取代普通刚玉磨料，同时由于采用新基体、新结合剂而使砂带寿命延长。

缓进给深磨是一种大切深和缓进给的高效磨削技术，它不但工效高，而且磨削精度高和加工表面质量好。特别是近几年来出现的一种集超高速 （150m/s~250m/s）、大切深（0.1mm~30mm）、快进给（0.5m/min~10m/min）于一体的高效深磨HEDG（High Efficiency Deep Grinding）新技术，它结合CBN砂轮与CNC技术，可使单位宽度砂轮上的材料磨除率高达2000mm3/mm·s~3000mm3/mm·s。用 此法磨削成形表面和沟槽零件（如转子槽、钻头上螺旋槽）时，可获得远高于切削加工的材料切除率。我国东北大学已制造出了大功率超高效深磨磨床，砂轮电动机 功率为55kW，磨削速度为250m/s。

四、超硬磨料磨削技术的新发展

由金刚石或CBN磨料制作的磨具称为超硬磨料磨具。由于其优良的磨削性能，现已广泛用于磨削技术各个方面，并成为超精密磨削、高效率磨削、难加工材料磨削、高精度成形磨削、磨削自动化和无人化等技术进步的基础。

金刚石和CBN磨料由于它们在加工材料适应方面的互补性，使由它们所构成的磨具可加工范围大为扩展，覆盖了包括各种高硬、高脆、高强韧性材料的几乎全部被加工材料。

金刚石磨具是磨削硬质合金、光学玻璃、陶瓷和形容词石等硬脆材料的最佳磨具，但因其在700℃~800℃时容易碳化，所以它不适于磨削钢铁材料及超高速磨 削。CBN磨料的出现导致磨削技术的革命，它能承受1300℃~1400℃的高温，对铁族元素化学惰性大，导热性好，磨钢料时的切除率高，磨削比大，磨具 寿命长，是磨削淬硬钢、高速钢、高强度钢、不锈钢和耐热合金等高硬度韧性大的金属的最佳磨料。此外，CBN磨具还适用于超高速磨削，金属基体CBN磨具线 速度超过250m/s也会不破碎。

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

影响金刚石圆锯片效率和寿命的因素有锯切工艺参数和金刚石的粒度、浓度、结合剂硬度等。据切能数有锯片线速、锯切浓度和进刀速度。

一、锯切参数

（1） 锯片线速度：在实际工作中，金刚石圆锯片的线速度受到设备条件、锯片质量和被锯切石才性质的限制。从最佳锯片使用寿命与锯切效率来说，应根据 不同石材的性质选择锯片的线速度。锯切花岗石时，锯片线速度可在25m～35m/s范围内选定。对于石英含量高而难于锯切的花岗石，锯片线速度取下限值为 宜。在生产花岗石面砖时，使用的金刚石圆锯片直径较小，线速度可以达到35m/s。

（2） 锯切深度：锯切深度是涉及金刚石磨耗、有效锯切、锯片受力情况和被锯切石材性质的重要参数。一般来讲，当金刚石圆锯片的线速度较高时，应选取小的切消深 度，从目前技术来说，锯切金刚石的深度可在1mm～10mm 之间选择。通常用大直径锯片锯切花岗石荒料时，锯切深度可控制在1mm～2mm之间，与此同时应降低进刀速度。当金刚石圆锯片的线速度较大时，应选取大的 切削深度。但当在锯机性能和刀具强度许可范围内，应尽量取较大的切削浓度进行切削，以提高切削效率。当对加工表面有要求时，则应采用小深度切削。

（3） 进刀速度：进刀速度即被锯切石材的进给速度。它的大小影响锯切率、锯片受力以及锯切区的散热情况。它的取值应根据被锯切石材的性质来选定。一般来讲，锯切 较软的石材，如大理石，可适当提高进刀速度，若进刀速度过低，更有利于提高锯切率。锯切细粒结构的、比较均质的花岗石，可适当提高进刀速度，若进刀速度过 低，金刚石刃容易被磨平。但锯切粗粒结构而软硬不均的花岗石时，应降低进刀速度，否则会引起锯片振动导致金刚石碎裂而降低锯切率。锯切花岗石的进刀速度一 般在9m～12m/min范围内选定。

二、其他影响因素

（1）金刚石粒度：常用的金刚石粒度在30/35～60/80范 围内。岩石愈坚硬，宜选取用较细的粒度。因为在同等压力条件下，金刚石愈细愈锋利， 有利于切入坚硬的岩石。另外，一般大直径的锯片要求锯切效率高，宜选取用较粗的粒度，如30/40，40/50；小直径的锯片锯切的效率低，要求岩石锯切 截面光滑，宜选用较细的粒度，如50/60，60/80。

（2）刀头浓度：所谓金刚石浓度，是指金刚石在工作层胎体中分布的密度（即单位 面积内所含金刚石的重量）。“规范”规定，每立方厘米工作胎体中含 4.4克拉的金刚石时，其浓度为100%，含3.3 克拉的金刚石时，其浓度为75%。体积浓度表示结块中金刚石所占体积的多少，并规定，当金刚石的体积占总体积的1/4时的浓度为100%。增大金刚石浓度 可望延长锯片的寿命，因为增加浓度即减小了每粒金刚石所受的平均切削力。但增加深度必然增加锯片的成本，因而存在一个最经济的浓度，且该浓度随铖切率增大 而增大。

（3） 刀头结合剂的硬度：一般来说，结合剂的硬度越高，其抗磨损能力越强。因而，当锯切研磨性大的岩石时，结合剂硬度宜高；当锯切材质软的岩石时，结合剂硬度宜低；当锯切研磨性大且硬的岩石时，结合剂硬度宜适中。

（4） 力效应、温度效应及磨破损：金刚石圆锯片在切割石材的过程中，会受到离心力、锯切力、锯切热等交变载荷的作用。由于力效应和温度效应而引起金刚石圆锯片的磨破捐损。

力效应：在锯切过程中，锯片要受到轴向力和切向力的作用。由于在圆周方向和径向存在力的作用，使得锯片在轴向呈波浪状，在径向呈碟状。这两种变形都会造成岩石切面不平直、石材浪费多、锯切时噪音大、振动加剧，造成金刚石结块早期破损、锯片寿命降低。

温度效应：传统理论认为：温度对锯片过程的影响主要表现在两个方面：一是导致结块中的金刚石石墨化；二是造成金刚石与胎体的热奕力而导致金刚石颗粒过早脱 落。新研究表明：切割过程中产生的热量主要传入结块。弧区温度不高，一般在40～120℃之间。而磨粒磨削点温度却较高，一般在250～700℃之间。而 冷却液只降低弧区的平均温度，对磨粒温度却影响较小。这样的温度不致使石墨炭化，却会使磨粒与工件之间摩擦性能发生变化，并使金刚石与添加剂之间发生热应 力，而导致金刚石失效机理发生根本性弯化。研究表明，温度效应是使锯片破损的最大影响因素。

磨破损：由于力效应和温度较应，锯片经过一段时间的使用往往会产生磨破损。磨破损的形式主要有以下几种：磨料磨损、局部破碎、大面积破碎、脱落、结合剂沿 锯切速度方向的机械擦伤。磨料磨损：金刚石颗粒与式件不断摩擦，棱边钝化成平面，失去切削性能，增大摩擦。锯切热会使金刚石颗粒表面出现石墨化薄层，硬度 大大降低，加剧磨损：金刚石颗粒表面承受交变的热应力，同时还承受交变的切削应力，就会出现疲劳裂纹而局部破碎，显露出锐利的新棱边，是较为理想的磨损形 态；大面积破碎：金刚石颗粒在切入切出时承受冲击载荷，比较突出的颗粒和晶粒过早消耗掉；脱落：交变的切削力使金刚石颗粒在结合剂中不断的被晃动而产生松 动。同时，锯切过程中的结合剂本身的磨损和锯切热使结合剂软化。这就使结合剂的把持力下降，当颗粒上的切削力大于把持力时，金刚石颗粒就会脱落。无论哪一 种磨损都与金刚石颗粒所承受的载荷和温度密切相关。而这两者都取决于铖切工艺和冷却润滑条件。

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

Na Galipedia, a wikipedia en galego.

ferro - cobalto - níquel Co Rh Ir
Xeral
Nome, símbolo, número	cobalto, Co, 27
Serie química	metal de transición
Grupo, período, bloque	9 , 4 , d
Densidade, dureza Mohs	8900 kg/m³, 5.0
Aparencia	metálico con tinte gris
Propiedades atómicas
Peso atómico	58,933200 uma
Radio medio†	135 pm
Radio atómico calculado	152 pm
Radio covalente	126 pm
Radio de Van der Waals	Sen datos pm
Configuración electrónica	[Ar]3d74s²
Estados de oxidación (Óxido)	2,3 (anfótero)
Estrutura cristalina	Hexagonal
Propiedades físicas
Estado da materia	Sólido (ferromagnético)
Punto de fusión	1768 K
Punto de ebulición	3200 K
Entalpía de vaporización	376,5 kJ/mol
Entalpía de fusión	16,19 kJ/mol
Presión de vapor	175 Pa a 1768 K
Velocidade do son	4720 m/s a 293,15 K
Información diversa
Electronegatividade	1,88 (Pauling)
Calor específico	420 J/(kg*K)
Condutividade eléctrica	17,2 106 m-1·Ω-1
Condutividade térmica	100 W/(m*K)
1° potencial de ionización	760,4 kJ/mol
2° potencial de ionización	1648 kJ/mol
3° potencial de ionización	3232 kJ/mol
4° potencial de ionización	4950 kJ/mol
Isótopos máis estables
iso. AN Vida media MD ED MeV PD 56Co Sintético 77,27 d ε 4,566 56Fe 57Co Sintético 271,79 d ε 0,836 57Fe 58Co Sintético 70,86 d ε 2,307 58Fe 59Co 100% Co es estable con 32 neutróns 60Co Sintético 5,2714 años β- 2,824 60Ni
Valores no SI e condicións normais (0 ºC e 1 atm), agás indicación en contra. †Calculado a partir de distintas lonxitudes de enlace covalente, metálico ou iónico.

O cobalto é un elemento químico de número atómico 27 e símbolo Co situado no grupo 9 da táboa periódica dos elementos.

[editar] Características principais

O cobalto é un metal duro, ferromagnético, de cor branca azulada. A súa temperatura de Curie é de 1388 K. Normalmente atópase xunto con níquel, e ambos adoitan formar parte dos meteoritos de ferro. É un elemento químico esencial para os mamíferos en pequenas cantidades. O Co-60, un radioisótopo de cobalto, é un importante trazador e axente no tratamento do cancro.

O cobalto metálico está comunmente constituído dunha mestura de dúas formas alotrópicas con estruturas cristalinas hexagonal e cúbica centrada nas caras sendo a temperatura de transición entre ambas de 722 K.

Presenta estados de oxidación baixos. Os compostos nos cales o cobalto ten un estado de oxidación de 4 son pouco comúns. O estado de oxidación 2 é moi frecuente, así como o 3. Tamén existen complexos importantes co estado de oxidación 1.

[editar] Aplicacións

Cristal decorativo, azul grazas a engadir cobalto. Feito a man en Bristol, Inglaterra.

• Aliaxes entre as que cabo sinalar superaliaxes usadas en turbinas de gas de aviación, aliaxes resistentes á corrosión, aceiros rápidos, e carburos cementados e ferramentas de diamante.
• Imans (Alnico) e cintas magnéticas.
• Catálise do petróleo e industria química.
• Recubrimentos metálicos por deposición electrolítica polo seu aspecto, dureza e resistencia á oxidación.
• Secante para pinturas, vernices e tintas.
• Recubrimento base de esmaltes vitrificados.
• Pigmentos (cobalto azul e cobalto verde).
• Electrodos de baterías eléctricas
• Cables de aceiro de pneumáticos.
• O Co-60 úsase como fonte de radiación gamma en radioterapia, esterilización de alimentos (pasteurización fría) e radiografía industrial para o control de calidade de metais (detección de gretas).

[editar] Papel biolóxico

O cobalto en pequenas cantidades é esencial para numerosos organismos, incluídos os humanos. A presenza de cantidades entre 0,13 e 0,30 ppm no chan mellora ostensiblemente a saúde dos animais de pastoreo. O cobalto é un compoñente central da vitamina B12 (cianocobalamina)

[editar] Historia

O elemento foi descuberto por George Brandt. A data do descubrimento varía nas diversas fontes entre 1730 e 1737. Brandt foi capaz de demostrar que o cobalto era o responsable da cor azul do vidro que previamente se atribuía ao bismuto.

O seu nome provén do alemán kobalt ou kobold, espírito maligno, chamado así polos mineiros pola súa toxicidade e os problemas que ocasionaba xa que do mesmo xeito que o níquel contaminaba e degradaba os elementos que se desexaba extraer.

Durante o século XIX, entre o 70 e 80% da produción mundial de cobalto obtíñase na fábrica norueguesa Blaafarveværket do industrial prusiano Benjamin Wegner.

En 1938 John Livingood e Glenn Seaborg descubriron o cobalto-60. A primeira máquina de radioterapia, bomba de cobalto, construída en Canadá por un equipo liderado por Ivan Smith e Roy Errington utilizouse nun paciente o 27 de outubro de 1951; o equipo atópase actualmente exposto no Saskatoon Cancer Centre, na cidade de Saskatoon (Saskatchewan).

[editar] Abundancia e obtención

O metal non se atopa en estado nativo, senón en diversos minerais, razón pola que se extrae usualmente xunto a outros produtos, especialmente como subproduto do níquel e o cobre. As principais menas de cobalto son a cobaltita, eritrina, cobaltocalcita e skuterudita. Os maiores produtores de cobalto son China, Zambia, Rusia e Australia.

[editar] Compostos

Debido aos varios estados de oxidación que presenta, existe un abundante número de compostos de cobalto. Os óxidos CoO (temperatura de Neel 291 K) e Co3Ou4 (temperatura de Neel 40 K) son ambos antiferromagnéticos a baixa temperatura.

[editar] Isótopos

O cobalto natural só ten un isótopo estable, o Co-59. Caracterizáronse 22 radioisótopos sendo os máis estables o Co-60, o Co-57 e o Co-56 con vidas medias de 5,2714 anos, 271,79 días e 70,86 días respectivamente. Os demais isótopos radioactivos teñen vidas medias inferiores a 18 horas e a maioría menores de 1 segundo. O cobalto presenta ademais catro metaestados, todos eles con vidas medias menores de 15 minutos.

A masa atómica dos isótopos do cobalto oscila entre 50 uma (Co-50) e 73 uma (Co-73). Os isótopos máis lixeiros có estable (Co-59) se desintegran principalmente por captura electrónica orixinando isótopos de ferro, mentres que os máis pesados có isótopo estable se desintegran por emisión beta dando lugar a isótopos de níquel.

O cobalto-60 úsase en radioterapia en substitución do radio polo seu menor prezo. Produce dous raios gamma con enerxías de 1,17 MeV e 1,33 MeV e ao ser a fonte empregada duns dous centímetros de radio provoca a aparición de zonas de penumbra dispersando a radiación en torno á dirección de radiación. O metal tende a producir un po moi fino que dificulta a protección fronte á radiación. A fonte de Co-60 ten unha vida útil de aproximadamente 5 anos, pero superado ese tempo segue sendo moi radioactiva, polo que estas fontes perderon, en certa medida, a súa popularidade en occidente.

[editar] Precaucións

O cobalto metálico en po finamente dividido é inflamable. Os compostos de cobalto en xeral deben manipularse con precaución pola lixeira toxicidade do metal.

O Co-60 é radioactivo e a exposición á súa radiación pode provocar cancro. A inxestión de Co-60 leva a acumulación dalgunha cantidade nos tecidos, cantidade que se elimina moi lentamente. Nunha eventual confrontación nuclear, a emisión de neutróns convertería o ferro en Co-60 multiplicando os efectos da radiación trala explosión e prolongando no tempo os efectos da contaminación radioactiva; con este propósito deséñanse algunhas armas nucleares denominadas bombas sucias (do inglés dirty bomb). En ausencia de guerra nuclear, o risco provén da inadecuada manipulación ou mantemento das unidades de radioterapia.

[editar] Véxase tamén

• Táboa periódica dos elementos

[editar] Ligazóns externas

• Enciclopedia Libre - Cobalto
• Os Alamos National Laboratory - Cobalto
• WebElements.com - Cobalto
• EnvironmentalChemistry.com - Cobalto
• Instituto Nacional de Seguridade e Hixiene no Traballo de España: Ficha internacional de seguridade química do cobalto.

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

Is dúil cheimiceach é cóbalt. Is é an meáchán adamhach atá aige ná 58.933195(5) g·mol−1. Tá uimhir adamhach 27 agus siombail Co air.

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

Koboltti (lat. cobaltum) on alkuaine, jonka kemiallinen merkki on Co, järjestysluku 27 ja CAS-numero 7440-48-4. Tiheys on 8,9 g/cm³. Sen sulamispiste on 1768 K (1495 °C) ja kiehumispiste 3200 K (2927 °C).

Koboltti on kova ferromagneettinen hopeanvalkoinen alkuaine. Se esiintyy usein nikkelin yhteydessä, ja molempia esiintyy meteoriittiraudassa. Nisäkkäät tarvitsevat pieniä määriä kobolttisuoloja. Koboltti-60 on keinotekoinen radioaktiivinen isotooppi, joka on tärkeä radioaktiivisuuden jäljitysaine ja sitä käytetään mm. elintarvikkeiden steriloinnissa ja syövän hoidossa.

Kobolttia käytetään metalliseoksissa, kuten superlejeerinkiosissa lentokoneiden suihkumoottoreissa, korroosion- ja vedenkestävissä seoksissa, myös timanttityökaluissa. Kobolttia käytetään myös magneeteissa ja magneettisena tallennusaineena, Alnico-magneeteissa, katalyytteinä kemianteollisuudessa ja elektrolyyttisenä päällysteenä, keramiikassa, maaleissa ja pariston elektrodeina.

Antiikin aikaan koboltin yhdisteillä värjättiin lasia syvänsiniseksi. Muinaisen Egyptin haudoista on löytynyt koboltilla värjättyjä esineitä. Kiinalaisten tiedetään käyttäneen sitä jo aiemmin. Koboltin keksijänä pidetään Georg Brandtia, joka osoitti 1730-luvulla, että koboltti aiheutti sinisen värin lasissa.

Hienojakoinen kobolttimetalli muodostaa tulipalovaaran. Kobolttiyhdisteitä tulisi käsitellä varoen johtuen koboltin lievästä myrkyllisyydestä.

[muokkaa] Koboltti ihmisen ravitsemuksessa

Koboltti on hivenaineena tärkeä monille eliöille, myös ihmiselle. Se on keskeinen komponentti B₁₂-vitamiinissa. Vaikka B₁₂-vitamiinia muodostuu paksusuolessa, sitä tarvitaan jonkin verran myös ravinnosta. Sen puutetta ei juuri esiinny muilla kuin kasvissyöjillä, sillä sitä on esimerkiksi simpukoissa, lohessa, sillissä, maksassa ja kananmunassa.

Kobolttia lasiputkessa

Kobolttimalmia

Bristolinsinistä lasia, sinisyys tulee koboltista

[muokkaa] Merkittävimmät esiintymisalueet

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

از ویکی‌پدیا، دانشنامهٔ آزاد.

کان‌سنگ کبالت.

کُبالت فلزی است سفید با علامت شیمیایی Co، شبیه نیکل ولی با ته رنگ آبی به جای ته رنگ زرد نیکل. از لحاظ شیمیایی فعالتر از نیکل است. در اسید سولفوریک و اسید نیتریک محلول و به کندی تحت تأثیر قلیایی‌ها قرار می‌‌گیرد. یرعت اکسایش کبالت ۲۵ برابر نیکل است. قدرت آن در سفید کردن آلیاژ‌های مس کمتر از نیکل بوده، ولی مقادیر کمی از آن در آلیاژهای نیکل- مس ته رنگ زرد نیکل را حنثی و آنها را سفید تر می‌‌کند. این فلز مانند نیکل دیامغناطیس بوده ولی تقریباً دارای ۳ برابر حداکثر نفوذ پذیری آن است. مانند تنگستن دارای خاصیت اضافه کردن سرخ سختی به آلیاژهای برشکاری است. همچنین به میزان بیشتر از نیکل سخت می‌‌کند به ویژه در مجاورت کربن، در آلیاژها می‌‌تواند بیشتر از نیکل ترکیبات شیمیایی دهد.

کبالت در جدول تناوبی.

کبالت دارای وزن مخصوص ۷۵۶/۸، نقطه ذوبی برابر ۱۴۹۳ درجه سانتی گراد، سختی برینل ۸۶، رسانایی الکتریکی حدود ۱۶ درصد مس است. استحکام کششی کبالت ریختگی خالص ۲۴ کیلوگرم بر میلیمتر مربع، ولی با اضافه کردن۲۵/۰ درصد کربن به ۵/۴۳ کیلوگرم بر میلیمتر مربع افزایش می‌‌یابد. این فلز در آلیاژهای برشکاری و فولادهای ابزار در آلیاژهای مغناطیسی بکار می‌رود.

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Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

Allikas: Vikipeedia

Koobalt on keemiline element järjenumbriga 27.

Tal on üks stabiilne isotoop massiarvuga 59.

Omadustelt on koobalt metall. Tema tihedus normaaltingimustel on 8,9 g/cm³ ja sulamistemperatuur 1495 Celsiuse kraadi.

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

Papel biológico [editar]

El cobalto en pequeñas cantidades es esencial para numerosos organismos, incluidos los humanos. La presencia de cantidades entre 0,13 y 0,30 ppm en el suelo mejora ostensiblemente la salud de los animales de pastoreo. El cobalto es un componente central de la vitamina B12 (cianocobalamina)

Historia [editar]

El elemento fue descubierto por George Brandt. La fecha del descubrimiento varía en las diversas fuentes entre 1730 y 1737. Brandt fue capaz de demostrar que el cobalto era el responsable del color azul del vidrio que previamente se atribuía al bismuto.

Su nombre proviene del alemán kobalt o kobold, espíritu maligno, llamado así por los mineros por su toxicidad y los problemas que ocasionaba ya que al igual que el níquel contaminaba y degradaba los elementos que se deseaba extraer.

Durante el siglo XIX, entre el 70 y 80% de la producción mundial de cobalto se obtenía en la fábrica noruega Blaafarveværket del industrial prusiano Benjamin Wegner.

En 1938 John Livingood y Glenn Seaborg descubrieron el cobalto-60. La primera máquina de radioterapia, bomba de cobalto, construida en Canadá por un equipo liderado por Ivan Smith y Roy Errington se utilizó en un paciente el 27 de octubre de 1951; el equipo se encuentra actualmente expuesto en el Saskatoon Cancer Centre, en la ciudad de Saskatoon (Saskatchewan).

Compuestos [editar]

Debido a los varios estados de oxidación que presenta, existe un abundante número de compuestos de cobalto. Los óxidos CoO (temperatura de Néel 291 K) y Co₃O₄ (temperatura de Néel 40 K) son ambos antiferromagnéticos a baja temperatura.

Isótopos [editar]

El cobalto natural solo tiene un isótopo estable, el Co-59. Se han caracterizado 22 radioisótopos siendo los más estables el Co-60, el Co-57 y el Co-56 con periodos de semidesintegración de 5,2714 años, 271,79 días y 70,86 días respectivamente. Los demás isótopos radioactivos tiene periodos de semidesintegración inferiores a 18 horas y la mayoría menores de 1 segundo. El cobalto presenta además cuatro metaestados, todos ellos con periodos de semidesintegración menores de 15 minutos.

La masa atómica de los isótopos del cobalto oscila entre 50 uma (Co-50) y 73 uma (Co-73). Los isótopos más ligeros que el estable (Co-59) se desintegran principalmente por captura electrónica originando isótopos de hierro, mientras que los más pesados que el isótopo estable se desintegran por emisión beta dando lugar a isótopos de níquel.

El cobalto-60 se usa en radioterapia en sustitución del radio por su menor precio (y considerando que el radio se desintegra en radon que es un elemento radiactivo y se presenta en forma de gas, por lo que es difícil encapsularlo para evitar contaminación radiactiva). Produce dos rayos gamma con energías de 1,17 MeV y 1,33 MeV y al ser la fuente empleada de unos dos centímetros de radio provoca la aparición de zonas de penumbra dispersando la radiación en torno a la dirección de radiación. El metal tiende a producir un polvo muy fino que dificulta la protección frente a la radiación. La fuente de Co-60 tiene una vida útil de aproximadamente 5 años, pero superado ese tiempo sigue siendo muy radioactivo, por lo que estas fuentes han perdido, en cierta medida, su popularidad en occidente.

Precauciones [editar]

El cobalto metálico en polvo finamente dividido es inflamable. Los compuestos de cobalto en general deben manipularse con precaución por la ligera toxicidad del metal.

El Co-60 es radiactivo y la exposición a su radiación puede provocar cáncer. La ingestión de Co-60 conlleva la acumulación de alguna cantidad en los tejidos, cantidad que se elimina muy lentamente. En una eventual confrontación nuclear, la emisión de neutrones convertiría el hierro en Co-60 multiplicando los efectos de la radiación tras la explosión y prolongando en el tiempo los efectos de la contaminación radioactiva; con este propósito se diseñan algunas armas nucleares denominadas bombas sucias (del inglés dirty bomb). En ausencia de guerra nuclear, el riesgo proviene de la inadecuada manipulación o mantenimiento de las unidades de radioterapia.

Referencias [editar]

1. ↑ Breve diccionario etimológico de la lengua castellana, Joan Corominas, Madrid, Gredos, 1961.

Enlaces externos [editar]

• Commons alberga contenido multimedia sobre Cobalto.Commons
• ATSDR en Español - ToxFAQs™: cobalto
• Enciclopedia Libre - Cobalto
• EnvironmentalChemistry.com - Cobalto
• Instituto Nacional de Seguridad e Higiene en el Trabajo de España: Ficha internacional de seguridad química del cobalto.
• Los Alamos National Laboratory - Cobalto
• WebElements.com - Cobalto

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Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

From Wikipedia, the free encyclopedia

27 iron ← cobalt → nickel - ↑ Co ↓ Rh
General
Name, Symbol, Number	cobalt, Co, 27
Chemical series	transition metals
Group, Period, Block	9, 4, d
Appearance	metallic with gray tinge
Standard atomic weight	58.933195(5) g·mol−1
Electron configuration	[Ar] 3d7 4s2
Electrons per shell	2, 8, 15, 2
Density (near r.t.)	8.90 g·cm−3
Liquid density at m.p.	7.75 g·cm−3
Melting point	1768 K (1495 °C, 2723 °F)
Boiling point	3200 K (2927 °C, 5301 °F)
Heat of fusion	16.06 kJ·mol−1
Heat of vaporization	377 kJ·mol−1
Heat capacity	(25 °C) 24.81 J·mol−1·K−1
Vapor pressure P/Pa 1 10 100 1 k 10 k 100 k at T/K 1790 1960 2165 2423 2755 3198
Atomic properties
Crystal structure	hexagonal
Oxidation states	2, 3 (amphoteric oxide)
Electronegativity	1.88 (Pauling scale)
Ionization energies (more)	1st: 760.4 kJ·mol−1
	2nd: 1648 kJ·mol−1
	3rd: 3232 kJ·mol−1
Atomic radius	135 pm
Atomic radius (calc.)	152 pm
Covalent radius	126 pm
Miscellaneous
Magnetic ordering	ferromagnetic
Electrical resistivity	(20 °C) 62.4 nΩ·m
Thermal conductivity	(300 K) 100 W·m−1·K−1
Thermal expansion	(25 °C) 13.0 µm·m−1·K−1
Speed of sound (thin rod)	(20 °C) 4720 m/s
Young's modulus	209 GPa
Shear modulus	75 GPa
Bulk modulus	180 GPa
Poisson ratio	0.31
Mohs hardness	5.0
Vickers hardness	1043 MPa
Brinell hardness	700 MPa
CAS registry number	7440-48-4
Selected isotopes
Main article: Isotopes of cobalt iso NA half-life DM DE (MeV) DP 56Co syn 77.27 d ε 4.566 56Fe 57Co syn 271.79 d ε 0.836 57Fe 58Co syn 70.86 d ε 2.307 58Fe 59Co 100% Co is stable with 32 neutrons 60Co syn 5.2714 years β- 2.824 60Ni
References
This box: view • talk • edit

Cobalt (IPA: /ˈkəʊbɒlt/) is a hard, lustrous, silver-grey metal, a chemical element with symbol Co. It is found in various ores, and is used in the preparation of magnetic, wear-resistant, and high-strength alloys. Its compounds are used in the production of inks, paints, and varnishes.

[edit] Notable characteristics

Cobalt is a silver or grey ferromagnetic element with atomic number 27. The Curie temperature is of 1388 K with 1.6~1.7 Bohr magnetons per atom. It is frequently associated with nickel, and both are characteristic ingredients of meteoric iron. Mammals require small amounts of cobalt salts. Cobalt-60, an artificially produced radioactive isotope of cobalt, is an important radioactive tracer and cancer-treatment agent. Cobalt has a relative permeability two thirds that of iron. Metallic cobalt commonly presents a mixture of two crystallographic structures hcp and fcc with a transition temperature hcp→fcc of 722 K.

Common oxidation states of cobalt include +2 and +3, though +1 is also seen.

[edit] Applications

[edit] Naturally occurring cobalt uses

• Alloys, such as
  • Superalloys, for parts in gas turbine aircraft engines.
  • Corrosion- and wear-resistant alloys.
  • High speed steels.
  • Cemented carbides (also called hard metals) and diamond tools.
• Magnets and magnetic recording media.
  • Alnico magnets.
  • Samarium-cobalt magnets.
• Catalysts for the petroleum and chemical industries.
• Electroplating because of its appearance, hardness, and resistance to oxidation.
• Drying agents for paints, varnishes, and inks.
• Ground coats for porcelain enamels.
• Pigments (cobalt blue and cobalt green).

Cobalt blue glass

• Lithium ion battery electrodes.
• Steel-belted radial tires.
• Purification of histidine-tagged fusion proteins in biotechnology applications.

[edit] Radioisotopes of Cobalt

Naturally occurring cobalt is composed of 1 stable isotope, ⁵⁹Co. 22 radioisotopes have been characterized with the most stable being ⁶⁰Co with a half-life of 5.2714 years, ⁵⁷Co with a half-life of 271.79 days, ⁵⁶Co with a half-life of 77.27 days, and ⁵⁸Co with a half-life of 70.86 days. All of the remaining radioactive isotopes have half-lives that are less than 18 hours and the majority of these have half-lives that are less than 1 second. This element also has 4 meta states, all of which have half-lives less than 15 minutes.

The isotopes of cobalt range in atomic weight from 50 u (⁵⁰Co) to 73 u (⁷³Co). The primary decay mode for isotopes with atomic mass unit values less than that of the most abundant stable isotope, ⁵⁹Co, is electron capture and the primary mode of decay for those of greater than 59 atomic mass units is beta decay. The primary decay products before ⁵⁹Co are element 26 (iron) isotopes and the primary products after are element 28 (nickel) isotopes.

[edit] Use of Cobalt radioisotopes in medicine

Cobalt-60 (Co-60 or ⁶⁰Co) is a radioactive metal that is used in radiotherapy. It produces two gamma rays with energies of 1.17 MeV and 1.33 MeV. The ⁶⁰Co source is about 2 cm in diameter and as a result produces a geometric penumbra, making the edge of the radiation field fuzzy. The metal has the unfortunate habit of producing a fine dust, causing problems with radiation protection. The ⁶⁰Co source is useful for about 5 years but even after this point is still very radioactive, and so cobalt machines have fallen from favor in the Western world where linacs are common. Cobalt with alloying additions of chromium and molybdenum is widely used as a bio-medical implant material.

Cobalt-57 (Co-57 or ⁵⁷Co) is a radioactive metal that is used in medical tests; it is used as a radiolabel for vitamin B-12 uptake. It is useful for the Schilling's test.^[2]

[edit] Industrial uses for radioactive isotopes

Cobalt-60 (Co-60 or ⁶⁰Co) is useful as a gamma ray source because it can be produced—in predictable quantity, and high activity—by simply exposing natural cobalt to neutrons in a reactor for a given time. It is used for

• sterilization of medical supplies, and medical waste;
• radiation treatment of foods for sterilization (cold pasteurization);
• industrial radiography (e.g., weld integrity radiographs);
• density measurements (e.g., concrete density measurements); and
• tank fill height switches.

[edit] History

Cobalt compounds have been used for centuries to impart a rich blue color to glass, glazes, and ceramics. Cobalt has been detected in Egyptian sculpture and Persian jewelry from the third millennium BC, in the ruins of Pompeii (destroyed AD 79), and in China dating from the Tang dynasty (AD 618–907) and the Ming dynasty (AD 1368–1644)^[3]. Cobalt glass ingots have been recovered from shipwrecks dating to the time of the Minoans^{[citation needed]}.

Swedish chemist Georg Brandt (1694–1768) is credited with isolating cobalt sometime between 1730 and 1737. He was able to show that cobalt was the source of the blue color in glass, which previously had been attributed to the bismuth found with cobalt.

During the 19th century, cobalt blue was produced at the Norwegian Blaafarveværket (70-80% of world production), led by the Prussian industrialist Benjamin Wegner.

In 1938, John Livingood and Glenn Seaborg discovered cobalt-60.

The word cobalt is derived from the German kobalt, from kobold meaning "goblin", a term used for the ore of cobalt by miners. The first attempts at smelting the cobalt ores to produce cobalt metal failed, yielding cobalt(II) oxide instead; not only that, but because of cobalt's curious affinity for arsenic, the primary ores of cobalt always contain arsenic, and upon smelting the arsenic oxidized into the highly toxic As₄O₆, which was breathed in by workers.

[edit] Biological role

Cobalt in small amounts is essential to many living organisms, including humans. Having 0.13 to 0.30 mg/kg of cobalt in soils markedly improves the health of grazing animals. Cobalt is a central component of the vitamin cobalamin, or vitamin B-12.

[edit] Occurrence

Cobalt ore

Cobalt output in 2005

Cobalt is not found as a native metal but generally found in the form of ores. Cobalt is usually not mined alone, and tends to be produced as a by-product of nickel and copper mining activities. The main ores of cobalt are cobaltite, erythrite, glaucodot, and skutterudite.

In 2005, the Democratic Republic of the Congo was the top producer of cobalt with almost 40% world share followed by Canada, Zambia, Russia, Brazil and Cuba, reports the British Geological Survey.

see also Category:Cobalt minerals

[edit] Compounds

There is a wide variety of cobalt compounds. The +2 and +3 oxidation states are most prevalent, however cobalt(I) complexes are also fairly common. Cobalt(II) salts form the red-pink [Co(OH₂)₆]²⁺ complex in aqueous solution. Adding excess chloride will also change the colour from pink to blue, due to the formation of [CoCl₄]^2-. Cobalt oxides are antiferromagnetic at low temperature: CoO (Neel temperature 291 K) and Co₃O₄ (Neel temperature: 40 K), which is analogous to magnetite (Fe₃O₄), with a mixture of +2 and +3 oxidation states. The oxide Co₂O₃ is probably unstable; it has never been synthesized. Other than Co₃O₄ and the brown fluoride CoF₃ (which is instantly hydrolyzed in water), all compounds containing cobalt in the +3 oxidation state are stabilized by complex ion formation.

see also Category:Cobalt compounds

[edit] Precautions

Powdered cobalt in metal form is a fire hazard.

Cobalt compounds should be handled with care due to cobalt's slight toxicity.

⁶⁰Co is a high-energy gamma ray emitter. Acute high-dose exposures to the gamma emissions, such as can occur when irradiation equipment is inadvertently diverted into scrap, can cause severe burns and death. Extended esposures increase the risk of morbidity or mortality from cancer.^[4]

Nuclear weapon designs could intentionally incorporate ⁵⁹Co, some of which which would be activated in a nuclear explosion to produce ⁶⁰Co. The ⁶⁰Co, dispersed as nuclear fallout, creates what is sometimes called a dirty bomb or cobalt bomb, once predicted by physicist Leó Szilárd as being capable of wiping out all life on earth.

[edit] References & notes

• Los Alamos National Laboratory: Cobalt

1. ^ Nuclides and Isotopes: Chart of the Nuclides, 16th Edition, by Edward Baum, Harold Knox, and Thomas Miller; Knolls Atomic Power Laboratory; 2002
2. ^ JPNM Physics Isotopes
3. ^ Encyclopedia Britannica Online.
4. ^ The Juarez accident

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Από τη Βικιπαίδεια, την ελεύθερη εγκυκλοπαίδεια

Το χημικό στοιχείο Κοβάλτιο είναι ένα μέταλλο με ατομικό αριθμό 27 και ατομικό βάρος 58,9332 . Έχει θερμοκρασία τήξης 1495 C° και θερμοκρασία βρασμού 2870 C°. Το σύμβολό του είναι Co.

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

Fra Wikipedia, den frie encyklopædi

27 – ↑ Co ↓ Rh

Udseende Gråligt, sølvskinnende metal Generelt Navn(e): Kobolt Kemisk symbol: Co Atomnummer: 27 Atommasse: 58.933195(5) g/mol Grundstofserie: Overgangsmetal Gruppe: 9 Periode: 4 Blok: d Elektronkonfiguration: [Ar] 3d7 4s2 Elektroner i hver skal: 2, 8, 15, 2 Kovalent radius: 126 pm Kemiske egenskaber Oxidationstrin: 2, 3 (amfoterisk oxid) Elektronegativitet: 1,88 (Paulings skala) Fysiske egenskaber Tilstandsform: Fast Krystalstruktur: Hexagonal Massefylde: 8,90 g/cm3 Massefylde på væskeform: 7,75 g/cm3 Smeltepunkt: 1495 °C Kogepunkt: 2927 °C Smeltevarme: 16,06 kJ/mol Fordampningsvarme: 277 kJ/mol Varmeledningsevne: (300 K) 100 W·m–1K–1 Varmeudvidelseskoeff.: 13,0 μm/(m·K) Elektrisk resistivitet: (20°C) 62,4 nΩ·m Magnetiske egenskaber: Ferromagnetisk Mekaniske egenskaber Youngs modul: 209 GPa Forskydningsmodul: 75 GPa Kompressibilitetsmodul: 180 GPa Poissons forhold: 0,31 Hårdhed (Mohs' skala): 5,0 Hårdhed (Vickers): 1043 MPa Hårdhed (Brinell): 700 MPa

Kobolt (opkaldt efter bjergtrolden Cobold, som ifølge den folkelige overtro i Tyskland spillede bjergmændene et puds, når udsmeltning af malm slog fejl) er det 27. grundstof i det periodiske system, og har det kemiske symbol Co: Under normale temperatur- og trykforhold optræder dette overgangsmetal som et gråt og sølvskinnende metal, der er hårdere end stål, men samtidig også skrøbeligt og "sprødt".

[redigér] Kemiske egenskaber

Kobolt "opfører" sig i kemisk henseende omtrent som jern og nikkel; det angribes ikke af atmosfærisk luft. I kemiske forbindelser optræder kobolt almindeligvis med oxidationstrin +2 og +3, og ved sjældnere lejligheder med oxidationstrin +1.

Glas farvet med kobolt

[redigér] Tekniske anvendelser

Allerede for 4000 år siden blev koboltholdige mineraler brugt som blåt farvestof i Ægypten. Metallisk kobolt bruges i legeringer, f.eks. hurtigstål, hvor de medvirker til at gøre materialet slidstærkt og korrosionsbestandigt, eller tilføjer magnetiske egenskaber, der bruges i magneter (alnico) og magnetiske medier som magnetbånd og disketter.

Kobolts modstandsdygtighed overfor korrosion udnyttes ved at galvanisere andre metaller med det. Kobolt bruges også til elektroder i batterier, som katalysator for en række industrielle kemiske processer, og det indgår i stoffer der hjælper maling, lak m.v. med at tørre.

Den radioaktive isotop kobolt-60 udsender gammastråling: Denne stråling bruges til radioterapi, til at sterilisere ting, der ikke tåler høje temperaturer, og til at opdage strukturelle skader indvendigt i metalemner.

[redigér] Historie

Kobolt er i århundreder blevet brugt til at give glas, glasur og keramik en intens blå farve i mange forskellige kulturer verden over. Opdagelsen af kobolt som et grundstof blev gjort af den svenske kemiker Georg Brandt engang i perioden fra 1730 til 1737: Han fandt ud af, at kobolt var kilden til den blå farve i glas, og ikke som man troede dengang, bismuth, der ofte findes sammen med kobolt.

Op igennem det 19. århundrede stod Blaafarveværket i Norge for 70 til 80 procent af verdensproduktionen.

[redigér] Forekomst og udvinding

Kobolt findes ikke i "fri", metallisk form i naturen, men i form af forskellige malme, primært koboltit, erytrit, glaucodot og skutterudit. Koboltforekomster er ofte "blandet op" med andre metallers malme, og af den grund udvindes kobolt typisk som et biprodukt fra udvindingen af kobber og nikkel.

Det meste kobolt udvindes i den Demokratiske Republik Congo, Folkerepublikken Kina, Zambia, Rusland og Australien, men også Finland, Aserbajdsjan og Kazakhstan råder over forekomster. Og i Ontario i Canada findes byen Cobalt (det engelske navn for kobolt), hvor kobolt udvindes som et biprodukt fra sølv-udvinding.

Sammen med nikkel indgår kobolt i det jern, man finder i meteoroider.

[redigér] Kobolt i biologien

Pattedyr har brug for små mængder af kobolt-holdige salte i deres føde; omking 0,2 mikrogram kobolt om dagen. Blandt andet indgår kobolt i B12-vitamin.

For meget kobolt i kosten (20–30 μg pr. dag) giver anledning til hudsygdomme og forgiftingssymptomer i organerne. Da man i Canada brugte kobolt til at stabilisere skummet på øl, steg dødeligheden blandt ihærdige øl-drikkere af, hvad der blev kaldt for "canadisk øldrikker-hjerte"; hjertets muskulatur var blevet svækket af store doser kobolt. Siden er man gået helt bort fra at bruge kobolt i ølproduktionen.

[redigér] Isotoper af kobolt

Naturligt forekommende kobolt består af én stabil isotop, kobolt-59 — dertil kendes 22 radioaktive isotoper, hvoraf kobolt-60 har den længste halveringstid med 5,2714 år. De øvrige isotoper har halveringstider fra ca. 9 måneder og nedefter.

Kobolt-59 kan omdannes til det stærkt radioaktive kobolt-60, når det bombarderes med neutroner: Den såkaldte koboltbombe er et atomvåben, som er designet til at udvikle store mængder kobolt-60 og dermed forøge strålingen fra det radioaktive nedfald.

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Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

U Cobaltu (simbulu Co) hè u 27imu elementu chimicu. A so massa atomica hè 58,9332 g/mol è a so densità hè 8,89 g/cm3 . U Cobaltu hè statu scupertu in u 1735 da Brandt.

[edit] Riferimenti

• Listinu di l'elementi chimichi annantu à a wikipedia in talianu è in francese

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

ferro - cobalt - níquel CO Rh Ir
General
Nom, símbol, nombre	cobalt, Co, 27
Sèrie química	metall de transició
Grup, període, bloc	9 , 4 , d
Densitat, duresa Mohs	8900 kg/m3, 5.0
Aparença	metàl·lic amb tint gris
Propietats atòmiques
Pes atòmic	58,933200 uma
Radi mitjà†	135 pm
Radi atòmic calculat	152 pm
Radi covalent	126 pm
Radi de Van der Waals	Sense dades pm
Configuració electrònica	[Ar]3d74s2
Estats d'oxidació (Òxid)	2,3 (amfòter)
Estructura cristal·lina	Hexagonal
Propietats físiques
Estat de la matèria	Sòlid (ferromagnètic)
Punt de fusió	1768 K
Punt d'ebullició	3200 K
Entalpia de vaporització	376,5 kJ/mol
Entalpia de fusió	16,19 kJ/mol
Pressió de vapor	175 Pa a 1768 K
Velocitat del so	4720 m/s a 293,15 K
Informació diversa
Electronegativitat	1,88 (Pauling)
Calor específica	420 J/(kg*K)
Conductivitat elèctrica	17,2 106 m-1·ohm-1
Conductivitat tèrmica	100 W/(m*K)
1er potencial d'ionització	760,4 kJ/mol
2on potencial d'ionització	1648 kJ/mol
3er potencial d'ionització	3232 kJ/mol
4t potencial d'ionització	4950 kJ/mol
Isòtops més estables
iso. AN Període de semidesintegració CD ED MeV PD 56Co Sintètic 77,27 dies ε 4,566 56Fe 57Co Sintètic 271,79 dies e 0,836 57Fe 58Co Sintètic 70,86 d e 2,307 58Fe 59Co 100% Co és estable amb 32 neutrons 60Co Sintètic 5,2714 anys β- 2,824 60Ni
Valors en el SI d'unitats i en CNPT (0º C i 1 atm), excepte quan s'indica el contrari.

El cobalt és un element químic de nombre atòmic 27 i símbol Co situat en el grup 9 de la taula periòdica dels elements.

[edita] Característiques principals

El cobalt és un metall dur, ferromagnètic, de color blanc blavós. La seva temperatura de Curie és de 1388 K. Normalment es troba junt amb níquel, i ambdós solen formar part dels meteorits de ferro. És un element químic essencial per als mamífers en petites quantitats. El Co-60, un radioisòtop de cobalt, és un important traçador i agent en el tractament del càncer.

El cobalt metàl·lic està comunament constituït d'una mescla de dos formes al·lotròpiques amb estructures cristal·lines hexagonal i cúbica centrada en les cares sent la temperatura de transició entre ambdós de 722 K.

Presenta estats d'oxidació baixos. Els compostos en els que el cobalt té un estat d'oxidació de +4 són poc comuns. L'estat d'oxidació +2 és molt freqüent, així com el +3. També hi ha complexos importants amb l'estat d'oxidació +1.

[edita] Aplicacions

• Aliatges entre les que cal assenyalar superaliatges usades en turbines de gas d'aviació, aliatges resistents a la corrosió, acers ràpids, i carburs cementats i eines de diamant.
• Imans (AlNiCo) i cintes magnètiques.
• Catàlisi del petroli i indústria química.
• Recobriments metàl·lics per deposició electrolítica pel seu aspecte, duresa i resistència a l'oxidació.
• Assecant per a pintures, vernissos i tintes.
• Recobriment base d'esmalts vitrificats.
• Pigments (cobalt blau i cobalt verd).
• Elèctrodes de bateries elèctriques
• Cables d'acer de pneumàtics.
• L'Isòtop Co-60 s'usa com a font de radiació gamma en radioteràpia, esterilització d'aliments (pasteurització freda) i radiografia industrial per al control de qualitat de metalls (detecció de clavills).

[edita] Rol biològic

El cobalt en petites quantitats és essencial per a nombrosos organismes, inclosos els humans. La presència de quantitats entre 0,13 i 0,30 ppm en el sòl millora ostensiblement la salut dels animals de pasturatge. El cobalt és un component central de la vitamina B12 (cianocobalamina).

[edita] Història

Material de vidre acolorit amb cobalt

L'element va ser descobert per George Brandt. La data del descobriment varia en les diverses fonts entre 1730 i 1737. Brandt va ser capaç de demostrar que el cobalt era el responsable del color blau del vidre que prèviament s'atribuïa al bismut.

El seu nom prové del alemany kobalt o kobold, esperit maligne, anomenat així pels miners per la seua toxicitat i els problemes que ocasionava ja que igual que el níquel contaminava i degradava els elements que es desitjava extraure.

Durant el segle XIX, entre el 70 i 80% de la producció mundial de cobalt s'obtenia en la fàbrica noruega Blaafarveværket de l'industrial prussià Benjamin Wegner.

El 1938 John Livingood i Glenn Seaborg van descobrir el cobalt-60. La primera màquina de radioteràpia, bomba de cobalt, construïda al Canadà per un equip liderat per Ivan Smith i Roy Errington es va utilitzar en un pacient el 27 d'octubre de 1951; l'equip es troba actualment exposat en el Saskatoon Càncer Centre, a la ciutat de Saskatoon (Saskatchewan).

[edita] Abundància i obtenció

Mena de Cobalt

El metall no es troba en estat natiu, sinó en diversos minerals, raó per la qual s'extrau usualment junt amb altres productes, especialment com a subproducte del níquel i el coure. Les principals menes de cobalt són la cobaltita, eritrina, cobaltocalcita i skuterudita.

Els majors productors de cobalt són la Xina, Zàmbia, Rússia i Austràlia.

[edita] Compostos

A causa dels diversos estats d'oxidació que presenta, hi ha un abundant nombre de compostos de cobalt. Els òxids CoO (temperatura de Neel 291 K) i Co₃O₄ (temperatura de Neel 40 K) són ambdós antiferromagnètics a baixa temperatura.

[edita] Isòtops

El cobalt natural només té un isòtop estable, el Co-59. S'han caracteritzat 22 radioisòtops sent els més estables el Co-60, el Co-57 i el Co-56 amb períodes de semidesintegració de 5,2714 anys, 271,79 dies i 70,86 dies respectivament. En els altres isòtops radioactius són inferiors a 18 hores i la majoria menors d'1 segon. El cobalt presenta a més quatre metaestats, tots ells amb períodes de semidesintegració menors de 15 minuts.

La massa atòmica dels isòtops del cobalt oscil·la entre 50 uma (Co-50) i 73 uma (Co-73). Els isòtops més lleugers que l'estable (Co-59) es desintegren principalment per captura electrònica originant isòtops de ferro, mentres que els més pesats que l'isòtop estable es desintegren per emissió beta donant lloc a isòtops de níquel.

El cobalt-60 s'usa en radioteràpia en substitució del radi pel seu menor preu. Produeix dos rajos gamma amb energies d'1,17 MeV i 1,33 MeV i al ser la font emprada d'uns dos centímetres de radi provoca l'aparició de zones de penombra dispersant la radiació entorn de la direcció de radiació. El metall tendeix a produir una pols molt fina que dificulta la protecció enfront de la radiació. La font de Co-60 té una vida útil d'aproximadament 5 anys, però superat aquest temps continua sent molt radioactiu, per la qual cosa aquestes fonts han perdut, en certa manera, la seva popularitat a occident.

[edita] Precaucions

El cobalt metàl·lic en pols finament dividit és inflamable. Els compostos de cobalt en general han de manipular-se amb precaució per la lleugera toxicitat del metall.

El Co-60 és radioactiu i l'exposició a la seva radiació pot provocar càncer. La ingestió de Co-60 comporta l'acumulació d'alguna quantitat en els teixits, quantitat que s'elimina molt lentament. En una eventual confrontació nuclear, l'emissió de neutrons convertiria el ferro en Co-60 multiplicant els efectes de la radiació després de l'explosió i prolongant en el temps els efectes de la contaminació radioactiva; amb aquest propòsit es dissenyen algunes armes nuclears denominades bombes brutes (de l'anglès dirty bomb). En absència de guerra nuclear, el risc prové de la inadequada manipulació o manteniment de les unitats de radioteràpia.

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.

27 Желязо ← Кобалт → Никел - ↑ Co ↓ Родий
Химическа серия	метал
Група, Период, Блок	8Б, 4,
Външен вид	синьо-сив метал
Свойства на атома
Атомна маса	58,9332 u
Атомен радиус (calc)	135 (152) pm
Ковалентен радиус	126 pm
Радиус на ван дер Ваалс	... pm
Електронна конфигурация	[Ar]3d74s2
e- на енергийно ниво	2, 8, 15, 2
Оксидационни състояния (Оксид)	амфотерни оксиди (2, 3)
Кристална структура	хексагонална
Физични свойства
Агрегатно състояние	твърдо
Плътност	8,9 kg/m³
Температура на топене	1768 K (1495 °C)
Температура на кипене	3200 K (2927 °C)
Моларен обем	6,67*10-3 m³/mol
Специфична топлина на топене	16,19 kJ/mol
Специфична топлина на изпарение	376,5 kJ/mol
Налягане на парата	1000 Pa при 2423 K
Скорост на звука	4720 m/s при 293,15 K
Други
Електроотрицателност	1,88 (скала на Паулинг)
Специфичен топлинен капацитет	420 J/(kg·K)
Специфична електропроводимост	17,2*106 S/m
Топлопроводимост	100 W/(m·K)
Йонизационен потенциал	kJ/mol
Периодична система на елементите

Кобалт- химичен елемент с атомен номер 27. Той е твърд, блестящ сиво-син метал.

[редактиране] История

В 15 век в Саксония сред богатите на сребро руди често са откривани блестящи, като стомана, бели или сиви кристали, от които не се е удавало да се стопи метал; техните примеси в сребърните или медните руди пречела на изливането на тези метали. Най-вероятно, това са били съдържащи арсен кобалтови минерали - кобалтин CoAsS, или сулфиди на кобалта.

[редактиране] Произход на името

Наименованието на химичния елемент произлиза от немската дума „Kobold“ — „дух“, „джудже“.

При нагряване на съдържащи арсен кобалтови минерали се отделя отровен газ - арсенов оксид. Рудата, съдържаща тези минерали, получава от миньорите името на духа Коболд. Древните норвежци са приписвали отравянето при леене на сребро на номерата на този зъл дух. Вероятно, името на този дух е с един корен с гръцкото „кобалос“ — „дим“. С тази дума гърците наричали още и лъжците.

През 1735 година шведският минералог Георг Бранд успява да отдели от такъв минерал неизвестен до тогава метал, който той назовава кобалт. Той открива, че именно съединенията на кобалта оцветяват стъклото в син цвят.

[редактиране] Добив

Кобалтът е относително рядък метал. В най-голяма степен кобалт съдъжат никеловите руди.

Първо рудата се обогатява и се получава концентрат, който се обработва със сярна киселина или амоняк за извличане на метала.

[редактиране] Приложение

Основно кобалтът се изразходва за получаване на сплави, тъй като повишава температурната устойчивост на стоманата. Той също така участва в някои твърдостопяеми сплави за изработването на режещи инструменти.

Особено важни са магнитните сплави на основа на кобалта, от които се изработват ламели за трансформатори и електрически двигатели.

Използването на кобалт при производството на стъкло го оцветяват в синьо.

Кобалтът се използва и за пигмент в някои бои.

[редактиране] Физични свойства

Кобалтът е твърд метал, съществуващ в две модификации. В диапазона на температурите от стайна до 427 °C устойчива α-модификация. В диапазона от 427 °C до температурата на топене (1495 °C) устойчива β-модификация. Кобалтът е феромагнетик, точка на Кюри - 1121 °C.

Тънкият слой окис му придават жълтеникав оттенък.

BW Bewise Inc. Willy Chen willy@tool-tool.com bw@tool-tool.com www.tool-tool.com skype:willy_chen_bw mobile:0937-618-190 Head &Administration Office No.13,Shiang Shang 2nd St., West Chiu Taichung,Taiwan 40356 TEL:+886 4 24710048 / FAX:+886 4 2471 4839 N.Branch 5F,No.460,Fu Shin North Rd.,Taipei,Taiwan S.Branch No.24,Sec.1,Chia Pu East Rd.,Taipao City,Chiayi Hsien,Taiwan

Welcome to BW tool world! We are an experienced tool maker specialized in cutting tools. We focus on what you need and endeavor to research the best cutter to satisfy users’ demand. Our customers involve wide range of industries, like mold & die, aerospace, electronic, machinery, etc. We are professional expert in cutting field. We would like to solve every problem from you. Please feel free to contact us, its our pleasure to serve for you. BW product including: cutting tool、aerospace tool .HSS Cutting tool、Carbide end mills、Carbide cutting tool、NAS Cutting tool、Carbide end mill、Aerospace cutting tool、Carbide drill、High speed steel、Milling cutter、Core drill、Tapered end mills、Metric end mills、Miniature end mills、Pilot reamer、Electronics cutter、Step drill、Metal cutting saw、Double margin drill、Gun barrel、Angle milling cutter、Carbide burrs、Carbide tipped cutter、Chamfering tool、IC card engraving cutter、Side cutter、NAS tool、DIN tool、Special tool、Metal slitting saws、Shell end mills、Side and face milling cutters、Side chip clearance saws、Long end mills、Stub roughing end mills、Dovetail milling cutters、Carbide slot drills、Carbide torus cutters、Angel carbide end mills、Carbide torus cutters、Carbide ball-nosed slot drills、Mould cutter、Tool manufacturer.