JPH01201475A - Production of tool coated with thin diamond film - Google Patents
Production of tool coated with thin diamond filmInfo
- Publication number
- JPH01201475A JPH01201475A JP2565488A JP2565488A JPH01201475A JP H01201475 A JPH01201475 A JP H01201475A JP 2565488 A JP2565488 A JP 2565488A JP 2565488 A JP2565488 A JP 2565488A JP H01201475 A JPH01201475 A JP H01201475A
- Authority
- JP
- Japan
- Prior art keywords
- diamond film
- substrate
- adhesion
- sintered body
- acid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000010432 diamond Substances 0.000 title claims abstract description 28
- 229910003460 diamond Inorganic materials 0.000 title claims abstract description 27
- 238000004519 manufacturing process Methods 0.000 title claims description 3
- 238000000034 method Methods 0.000 claims abstract description 10
- 238000005530 etching Methods 0.000 claims abstract description 8
- 239000011248 coating agent Substances 0.000 claims abstract description 4
- 238000000576 coating method Methods 0.000 claims abstract description 4
- 238000010306 acid treatment Methods 0.000 claims abstract description 3
- 239000002344 surface layer Substances 0.000 claims abstract 3
- 239000000126 substance Substances 0.000 claims abstract 2
- 239000012808 vapor phase Substances 0.000 claims abstract 2
- 239000010409 thin film Substances 0.000 claims description 6
- 239000010941 cobalt Substances 0.000 claims description 3
- 229910017052 cobalt Inorganic materials 0.000 claims description 3
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims description 3
- UONOETXJSWQNOL-UHFFFAOYSA-N tungsten carbide Chemical compound [W+]#[C-] UONOETXJSWQNOL-UHFFFAOYSA-N 0.000 claims 1
- 239000000758 substrate Substances 0.000 abstract description 30
- 229910009043 WC-Co Inorganic materials 0.000 abstract description 10
- 239000002253 acid Substances 0.000 abstract description 9
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 abstract description 4
- 229910017604 nitric acid Inorganic materials 0.000 abstract description 4
- 239000010408 film Substances 0.000 description 19
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 5
- 239000007789 gas Substances 0.000 description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 2
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- QZPSXPBJTPJTSZ-UHFFFAOYSA-N aqua regia Chemical compound Cl.O[N+]([O-])=O QZPSXPBJTPJTSZ-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 239000003822 epoxy resin Substances 0.000 description 2
- 238000009501 film coating Methods 0.000 description 2
- 230000006911 nucleation Effects 0.000 description 2
- 238000010899 nucleation Methods 0.000 description 2
- 238000007517 polishing process Methods 0.000 description 2
- 229920000647 polyepoxide Polymers 0.000 description 2
- 238000009864 tensile test Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000004215 Carbon black (E152) Substances 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 229930195733 hydrocarbon Natural products 0.000 description 1
- 150000002430 hydrocarbons Chemical class 0.000 description 1
- 238000002065 inelastic X-ray scattering Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- -1 methane using plasma Chemical class 0.000 description 1
- 230000001443 photoexcitation Effects 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 238000002233 thin-film X-ray diffraction Methods 0.000 description 1
Landscapes
- Chemical Vapour Deposition (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、ダイヤモンド薄膜コーティング法に係り、特
に、Ｗ Ｃ−Ｃｏ基体との密着性に優れたダイヤモンド
薄膜コーティング工具の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a diamond thin film coating method, and particularly to a method for manufacturing a diamond thin film coated tool that has excellent adhesion to a WC-Co substrate.
薄膜コーティング工具は、現在、ＷＣ−Ｃｏ焼結基体上
に、ＴｉＮ、ＴｉＣをコーティングしたものが主流とな
っている。しかし、工具の寿命延長、研削能力の向上、
仕上げ表面精度の向上環から、より硬度の高いコーティ
ング工具に対する要求が高まっている。Currently, the mainstream of thin film coating tools is one in which a WC-Co sintered substrate is coated with TiN or TiC. However, extending tool life, improving grinding ability,
Demand for coated tools with higher hardness is increasing due to improved surface finish accuracy.
一方、炭化水素−水素混合ガスのプラズマ等を利用した
化学気相法（ＣＶＤ）により粒子、又は。On the other hand, particles or particles are produced by chemical vapor deposition (CVD) using plasma of a hydrocarbon-hydrogen mixed gas.
膜状ダイヤモンドの合成が可能となっている。ダイヤモ
ンド膜を工具のコーティングに利用する場合、基体との
密着力の向上が重要課題となる。基体との密着力を向上
させる方法として、特開昭６２−１０８７９９号公報に
みられるように、基体を研磨粉で研磨する方法がある。It has become possible to synthesize film-like diamonds. When using diamond films to coat tools, improving the adhesion to the substrate is an important issue. As a method of improving the adhesion to the substrate, there is a method of polishing the substrate with polishing powder, as disclosed in Japanese Patent Application Laid-Open No. 108799/1983.
これは、研磨粉で基体の表面に傷をつけ、ダイヤモンド
の核発生密度を増大させ、表面積を増大させて密着力を
向上させる。This scratches the surface of the substrate with abrasive powder, increases the density of diamond nucleation, increases the surface area, and improves adhesion.
この方法により密着力は向上するが、ＷＣは非常に硬い
材料であり、効率よく基体表面を研磨するには、高価な
ダイヤモンド粒子、又は、ＣＢＮ粒子を使う必要がある
。また、手間がかかる研磨工程が必要となる。Although this method improves adhesion, WC is a very hard material, and in order to efficiently polish the substrate surface, it is necessary to use expensive diamond particles or CBN particles. Furthermore, a time-consuming polishing process is required.
本発明の目的は、Ｗ Ｃ−Ｇ ｏ焼結基体−ヒに、安価
で密着力の大きいダイヤモンド薄膜のコーテイング方法
を提供することにある。An object of the present invention is to provide a method of coating a diamond thin film on a WC-Go sintered substrate at low cost and with high adhesion.
ＷＣ−Ｃｏ焼結基体は、ＷＣとｃｏの超微粉（１μｒｎ
又はそれ以下）を焼結して造られる。ＷＣは耐酸性が強
いが、ＣＯは酸に容易に溶解する。The WC-Co sintered base is made of ultrafine powder of WC and co (1 μrn
or smaller) by sintering. WC has strong acid resistance, but CO easily dissolves in acid.
従って、Ｗ Ｃ−Ｃｏ焼結基体を硝酸等の酸に浸漬する
ことにより、基体の表面に微細な凹凸の傷をつけること
ができ、また、ダイヤモンドの結晶核が発生し難いＣＯ
を選択的に除去できるので、核発生密度、及び、接着表
面積の増大が図れ、密着力の大きいダイヤモンド膜が形
成できる。Therefore, by immersing the WC-Co sintered substrate in an acid such as nitric acid, it is possible to make fine scratches on the surface of the substrate, and it is also possible to immerse the WC-Co sintered substrate in an acid such as nitric acid.
can be selectively removed, the nucleation density and adhesion surface area can be increased, and a diamond film with high adhesion can be formed.
以下、本発明の一実施例を第１図を用いて説明する。１
はＷＣ−Ｃｏ焼結基体で、大きさは１５ｎｎ×１５１ｆ
ｆ１１×５ｎｎｈ前後である。Ｃｏの含有量は数％〜十
数％が多い。界面２は、酸エツチング等によりｃｏが溶
出し傷がつけられている。酸は、濃塩酸、濃硝酸等をそ
のまま、又は、水で希釈して用いることができるが、よ
りエツチング能力の大きい王水が好適である。３は、ダ
イヤモンド膜、又は、ダイヤモンド状炭素膜である。ダ
イヤモンド膜、又は、ダイヤモンド状炭素膜は、水素と
メタン等の炭化水素等の混合ガスをプラズマ、又は、熱
フィラメント、光励起反応等により分解することにより
形成される。混合ガスのプラズマを形成するには、マイ
クロ波、高周波等の電磁波エネルギ、又は、直流電源を
利用することができる。An embodiment of the present invention will be described below with reference to FIG. 1
is a WC-Co sintered base, the size is 15nn x 151f
It is around f11×5nnh. The Co content is often from several percent to more than ten percent. The interface 2 is scratched by elution of cobalt by acid etching or the like. As the acid, concentrated hydrochloric acid, concentrated nitric acid, etc. can be used as they are or diluted with water, but aqua regia is preferred as it has a higher etching ability. 3 is a diamond film or a diamond-like carbon film. A diamond film or a diamond-like carbon film is formed by decomposing a mixed gas such as hydrogen and a hydrocarbon such as methane using plasma, a hot filament, a photoexcitation reaction, or the like. To form a mixed gas plasma, electromagnetic wave energy such as microwaves and high frequency waves, or a DC power source can be used.
以下、具体的実施例を用いて本発明をさらに詳細に説明
する。Hereinafter, the present invention will be explained in more detail using specific examples.
〔実施例１〕
１５ ｍ Ｘ １５ ｍｍ Ｘ ５ ｍｍ ｈのＷＣ−
Ｃｏ焼結基体（Ｇｏ含有率６ｗｔ％）を王水中に３０分
間浸漬して表面をエツチング処理し、水洗後乾燥させた
。[Example 1] WC- of 15 m x 15 mm x 5 mm h
A Co sintered substrate (Go content: 6 wt%) was immersed in aqua regia for 30 minutes to etching the surface, washed with water, and then dried.
この基体を、内径４０ｎｎ＋φ、長さ１ｍの石英ガラス
製プラズマ反応器の多孔板上に設置し、反応器上部より
水素９９ｖｏ １％＋メタンｌｖｏ １％の混合ガスを
供給しながら基体部にマイクロ波（２，４５Ｇ１−Ｉｚ
、１．０ＫＷ）を印加してプラズマを発生させこの基体
上に約２μｍ厚さのダイヤモンド膜を形成した。ダイヤ
モンド膜の形成条件は、基体温度８００℃、圧力２Ｑｔ
ｏｒｒ、工時間で、ダイヤモンド膜の同定は薄膜Ｘ線回
折とラマンスペクトルにより行なった。This substrate was placed on a perforated plate of a quartz glass plasma reactor with an inner diameter of 40 nn + φ and a length of 1 m, and while a mixed gas of hydrogen 99vo 1% + methane lvo 1% was supplied from the top of the reactor, microwaves were applied to the substrate. (2,45G1-Iz
, 1.0 KW) was applied to generate plasma, and a diamond film with a thickness of about 2 μm was formed on this substrate. The conditions for forming the diamond film are a substrate temperature of 800°C and a pressure of 2Qt.
The diamond film was identified by thin film X-ray diffraction and Raman spectroscopy.
ダイヤモンド膜の基体との密着力はエポキシ樹脂を接着
剤として用いた引張り試験法により測定し、１７０ｋｇ
／ａＪの密着強度を得た。この値は、ＴｉＮやＴｉＣ膜
の密着強度２００〜３０ＯｋｇＺｄより多少小さいが充
分コーティング工具膜として使用に耐えるものである。The adhesion strength of the diamond film to the substrate was measured by a tensile test method using epoxy resin as an adhesive.
An adhesion strength of /aJ was obtained. Although this value is somewhat smaller than the adhesion strength of TiN or TiC film, which is 200 to 30 kgZd, it is sufficient to withstand use as a coating tool film.
実施例１と同じ装置を用い、酸エツチングの前処理をし
ないＷ Ｃ−Ｃｏ基体表面上に、実施例１と同じ条件下
で約２μｍ厚さのダイヤモンド膜を形成した。このダイ
ヤモンド膜の基体との密着力をエポキシ樹脂を接着剤と
して用いた引張り試験法により測定した。密着強度は、
２３ｋｇ／ａＪであった。Using the same equipment as in Example 1, a diamond film with a thickness of approximately 2 μm was formed under the same conditions as in Example 1 on the surface of a W C-Co substrate that was not pretreated with acid etching. The adhesion of this diamond film to the substrate was measured by a tensile test method using an epoxy resin as an adhesive. The adhesion strength is
It was 23 kg/aJ.
実施例１及び比較例の結果から、Ｗ Ｃ−Ｇ ｏ基体の
表面を酸エツチング処理することによりダイヤモンド膜
と、Ｗ Ｃ−Ｃｏ基体との密着力を大巾に向上すること
ができる。From the results of Example 1 and Comparative Example, the adhesion between the diamond film and the WC-Co substrate can be greatly improved by acid etching the surface of the WC-Go substrate.
〔実施例２〕
実施例１と同じ装置を用い、ｌｏ＋＋ｒｉＸ１０ｍｍＸ
２ ｍ ｈのＷＣ基体及び１０ｎｙｎＸ １０ｎｗｎ
Ｘ ０．５ｍｍｈのＣｏ基体上へのダイヤモンド膜の合
成を実施例１と同一条件下で試みた。[Example 2] Using the same equipment as in Example 1, lo++riX10mmX
2m h WC substrate and 10nynX 10nwn
Synthesis of a diamond film on a Co substrate of x 0.5 mmh was attempted under the same conditions as in Example 1.
実験の結果、ＷＣ基体上にはダイヤモンド膜が形成され
たが、Ｃｏ基体上には黒鉛構造の炭素ができダイヤモン
ド膜が形成できなかった。また、Ｃｏ基体の場合、密着
性も弱かった。したがって、ＷＣ−Ｃｏ基体の酸処理に
より、Ｃｏを選択的に除去してやれば密着性、硬度の小
さい黒鉛の生成を抑制することもできる。As a result of the experiment, a diamond film was formed on the WC substrate, but carbon with a graphite structure was formed on the Co substrate, and no diamond film could be formed on the Co substrate. Furthermore, in the case of the Co substrate, the adhesion was also weak. Therefore, if Co is selectively removed by acid treatment of the WC-Co substrate, it is also possible to suppress the formation of graphite with low adhesion and hardness.
本発明によれば、基体との密着性の優れたダイヤモンド
膜を安価に量産することができる。According to the present invention, a diamond film having excellent adhesion to a substrate can be mass-produced at low cost.
図は、本発明の一実施例の断面図である。 The figure is a sectional view of one embodiment of the present invention.
Claims (1)
面層のコバルトを酸処理により選択エッチングした後、
化学気相法によりダイヤモンド薄膜をコーティングする
ことを特徴とするダイヤモンド薄膜コーティング工具の
製造方法。1. After selectively etching the cobalt on the surface layer of the tungsten carbide/cobalt sintered chip using acid treatment,
A method for manufacturing a diamond thin film coated tool, which comprises coating a diamond thin film using a chemical vapor phase method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2565488A JPH01201475A (en) | 1988-02-08 | 1988-02-08 | Production of tool coated with thin diamond film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2565488A JPH01201475A (en) | 1988-02-08 | 1988-02-08 | Production of tool coated with thin diamond film |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01201475A true JPH01201475A (en) | 1989-08-14 |
Family
ID=12171805
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2565488A Pending JPH01201475A (en) | 1988-02-08 | 1988-02-08 | Production of tool coated with thin diamond film |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01201475A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1991004353A1 (en) * | 1989-09-22 | 1991-04-04 | Showa Denko Kabushiki Kaisha | Vapor deposited diamond synthesizing method on electrochemically treated substrate |
| JPH03115571A (en) * | 1989-09-28 | 1991-05-16 | Toshiba Tungaloy Co Ltd | Diamond-coated sintered alloy excellent in adhesive strength and its production |
| US5236740A (en) * | 1991-04-26 | 1993-08-17 | National Center For Manufacturing Sciences | Methods for coating adherent diamond films on cemented tungsten carbide substrates |
| JPH05311443A (en) * | 1991-03-26 | 1993-11-22 | Semiconductor Energy Lab Co Ltd | Production of diamond coated member |
| US5585176A (en) * | 1993-11-30 | 1996-12-17 | Kennametal Inc. | Diamond coated tools and wear parts |
| US5716170A (en) * | 1996-05-15 | 1998-02-10 | Kennametal Inc. | Diamond coated cutting member and method of making the same |
| US6660329B2 (en) | 2001-09-05 | 2003-12-09 | Kennametal Inc. | Method for making diamond coated cutting tool |
| WO2011018917A1 (en) * | 2009-08-11 | 2011-02-17 | 住友電気工業株式会社 | Diamond-coated tool |
-
1988
- 1988-02-08 JP JP2565488A patent/JPH01201475A/en active Pending
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1991004353A1 (en) * | 1989-09-22 | 1991-04-04 | Showa Denko Kabushiki Kaisha | Vapor deposited diamond synthesizing method on electrochemically treated substrate |
| US5164051A (en) * | 1989-09-22 | 1992-11-17 | Showa Denko K. K. | Method for vapor phase synthesis of diamond on electrochemically treated substrate |
| JPH03115571A (en) * | 1989-09-28 | 1991-05-16 | Toshiba Tungaloy Co Ltd | Diamond-coated sintered alloy excellent in adhesive strength and its production |
| JPH05311443A (en) * | 1991-03-26 | 1993-11-22 | Semiconductor Energy Lab Co Ltd | Production of diamond coated member |
| US5236740A (en) * | 1991-04-26 | 1993-08-17 | National Center For Manufacturing Sciences | Methods for coating adherent diamond films on cemented tungsten carbide substrates |
| US6287682B1 (en) | 1993-11-30 | 2001-09-11 | Kennametal Pc Inc. | Diamond coated tools and process for making |
| US5648119A (en) * | 1993-11-30 | 1997-07-15 | Kennametal Inc. | Process for making diamond coated tools and wear parts |
| US5585176A (en) * | 1993-11-30 | 1996-12-17 | Kennametal Inc. | Diamond coated tools and wear parts |
| US5716170A (en) * | 1996-05-15 | 1998-02-10 | Kennametal Inc. | Diamond coated cutting member and method of making the same |
| US6660329B2 (en) | 2001-09-05 | 2003-12-09 | Kennametal Inc. | Method for making diamond coated cutting tool |
| US6890655B2 (en) | 2001-09-05 | 2005-05-10 | Kennametal Inc. | Diamond coated cutting tool and method for making the same |
| WO2011018917A1 (en) * | 2009-08-11 | 2011-02-17 | 住友電気工業株式会社 | Diamond-coated tool |
| JP2011038150A (en) * | 2009-08-11 | 2011-02-24 | Sumitomo Electric Ind Ltd | Diamond coated tool |
| JP4690479B2 (en) * | 2009-08-11 | 2011-06-01 | 住友電気工業株式会社 | Diamond coated tools |
| US9302327B2 (en) | 2009-08-11 | 2016-04-05 | Sumitomo Electric Industries, Ltd. | Diamond coated tool |
| US9731355B2 (en) | 2009-08-11 | 2017-08-15 | Sumitomo Electric Industries, Ltd. | Diamond coated tool |
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