JP2584805B2 - Method for synthesizing diamond particles - Google Patents
Method for synthesizing diamond particlesInfo
- Publication number
- JP2584805B2 JP2584805B2 JP62320141A JP32014187A JP2584805B2 JP 2584805 B2 JP2584805 B2 JP 2584805B2 JP 62320141 A JP62320141 A JP 62320141A JP 32014187 A JP32014187 A JP 32014187A JP 2584805 B2 JP2584805 B2 JP 2584805B2
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- diamond
- diamond particles
- gas
- plasma
- particles
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- Carbon And Carbon Compounds (AREA)
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- General Engineering & Computer Science (AREA)
Description
【発明の詳細な説明】 〔概 要〕 本発明は、熱プラズマジェットによりダイヤモンドを
気相合成する方法に関し、 粒径の均一なダイヤモンド粒子を簡単な装置で単純な
工程により連続的に高収率で安価に製造することを目的
とし、 プラズマトーチを用い、アーク放電により発生せしめ
た熱プラズマをプラズマジェットとして噴出させ、これ
にダイヤモンド粒子を含むパウダーガスを噴射させて熱
プラズマを急冷させることによりダイヤモンド粒子の表
面にダイヤモンドを気相成長させ、かつ反応ガスを分粒
器を含む循環系中を通して循環せしめることにより高い
収率で、粒径の均一なダイヤモンド粒子を気相成長させ
る。DETAILED DESCRIPTION OF THE INVENTION [Summary] The present invention relates to a method for vapor-phase synthesis of diamond by a thermal plasma jet. By using a plasma torch, a thermal plasma generated by arc discharge is ejected as a plasma jet, and a powder gas containing diamond particles is injected into the plasma jet to rapidly cool the thermal plasma. Diamond is vapor-phase-grown on the surface of the particles, and the reaction gas is circulated through a circulation system including a particle sizer, whereby diamond particles having a uniform particle diameter are vapor-phase-grown with a high yield.
本発明はダイヤモンド粒子の合成方法に関し、更に詳
しくは陰極及び陽極を有するDCプラズマトーチを用い、
DCアーク放電により発生せしめた熱プラズマをプラズマ
ジェットとして噴出させ、これにダイヤモンド粒子を含
むパウダーガスを噴射させて熱プラズマガスを急冷させ
ることによりダイヤモンド粒子の表面に粒径のそろった
ダイヤモンドを低価格で連続的に気相成長させる方法に
関する。The present invention relates to a method for synthesizing diamond particles, more particularly using a DC plasma torch having a cathode and an anode,
Thermal plasma generated by DC arc discharge is ejected as a plasma jet, and a powder gas containing diamond particles is injected into the plasma jet to quench the thermal plasma gas, resulting in a low-cost diamond with a uniform diameter on the surface of the diamond particles. And a method of continuously performing vapor phase growth.
ダイヤモンドは炭素（Ｃ）の同素体であり、所謂ダイ
ヤモンド構造を示し、モース（Mohs）硬度10とあらゆる
物質の中で最も硬度の大きい材料であり、また熱伝導度
は1000W/mkと他の材料より格段に優れている。Diamond is an allotrope of carbon (C), and has a so-called diamond structure. It has the Mohs hardness of 10 and is the hardest material among all substances, and has a thermal conductivity of 1000 W / mk, which is higher than other materials. It is much better.
また、同じ同素体で非晶質ではあるが透明で絶縁物で
あるダイヤモンド状炭素があり、このものはダイヤモン
ドより劣るが高い熱伝導度と硬度を示している。In addition, there is diamond-like carbon which is the same allotrope but is amorphous but transparent and an insulator, and has a lower thermal conductivity and higher hardness than diamond.
これらのことからダイヤモンドは各種の用途が期待さ
れており、例えば、硬度が大きいことを利用してダイヤ
モンド砥粒は高硬度金属やファインセラミックスの加工
用として広く用いられており、これらの加工には必要不
可欠なものである。From these facts, diamond is expected to have various uses, for example, diamond abrasive grains are widely used for processing high hardness metals and fine ceramics due to their high hardness. Indispensable.
ダイヤモンド砥粒は、従来、高温高圧法や衝撃法で一
般に製造されていたが、これらの方法は、大型の設備が
必要で、しかもバッチ処理であり、更に反応精製物が金
属やグラファイトとの混合物であるため、ダイヤモンド
の分離、さらには分粒の後工程が必要であり、工業的製
造方法としてはその製造工程及び価格の両面で充分なも
のではなかった。Conventionally, diamond abrasive grains have been generally manufactured by a high-temperature and high-pressure method or an impact method.However, these methods require large-scale equipment, are batch processes, and furthermore, the reaction purified product is a mixture of a metal and graphite. Therefore, a post-step of separation of diamond and further sizing is required, and it is not sufficient as an industrial production method in terms of both the production process and the price.
前記したように、従来のダイヤモンド砥粒の製造方法
は製造工程及び価格の点で工業的な方法としては不充分
なものであり、本発明はかかる問題を解決して粒径の均
一なダイヤモンド粒子を簡単な装置で単純な工程により
連続的に高収率で安価に製造することを目的とする。As described above, the conventional method for producing diamond abrasive grains is inadequate as an industrial method in terms of the production process and price, and the present invention solves such a problem and solves the above-mentioned problem by providing a diamond particle having a uniform particle size. It is an object of the present invention to continuously and inexpensively produce a high yield with a simple apparatus and a simple process.
前記目的は、本発明に従えば、プラズマトーチを用
い、アーク放電により発生せしめた熱プラズマをプラズ
マジェットとして噴出させ、これにダイヤモンド粒子を
含むパウダーガスを噴射させて熱プラズマを急冷させる
ことによりダイヤモンド粒子の表面にダイヤモンドを気
相成長させ、かつ反応ガスを分粒器を含む循環系中を通
して循環せしめることにより高い収率で、粒径の均一な
ダイヤモンド粒子を気相成長させることによって解決さ
れる。According to the present invention, according to the present invention, a plasma torch is used to eject thermal plasma generated by arc discharge as a plasma jet, and a powder gas containing diamond particles is injected into the plasma jet to rapidly cool the thermal plasma. The problem is solved by vapor-depositing diamond particles of uniform size in high yield by vapor-growing diamond on the surface of the particles and circulating the reaction gas through a circulation system including a particle sizer. .
本発明は、我々が先に特願昭62−83318（昭和62年４
月３日出願）において提案した良質のダイヤモンドを高
速で合成できるプラズマジェットCVD装置を使用したダ
イヤモンドの化学気相成長方法を用いて均一な粒径を有
するダイヤモンド粒子を単純な工程で安価に合成するも
のである。The present invention was disclosed in Japanese Patent Application No. 62-83318 (April 4, 1987).
The diamond particles having a uniform particle size are synthesized in a simple process at a low cost by using a chemical vapor deposition method of diamond using a plasma jet CVD apparatus capable of synthesizing good quality diamond at a high speed proposed on March 3, 2009. Things.
第１図は本発明に従ったダイヤモンド粒子の製造プロ
セスを示す概略図面であり、第１図において、１は陰
極、２は陽極、３はプラズマジェット、４はパウダーガ
ス、５は放電ガス配管、６はパウダーガス配管、７はチ
ャンバー、８はポンプ、９は分粒器、10は粉末捕集器、
11は分粒器、12は水素ガス（H2）ボンベ、13はメタンガ
ス（CH4）ボンベ、14は流量計、15はパウダーフィーダ
ー、16はアーク電源である。FIG. 1 is a schematic view showing a process for producing diamond particles according to the present invention. In FIG. 1, 1 is a cathode, 2 is an anode, 3 is a plasma jet, 4 is a powder gas, 5 is a discharge gas pipe, 6 is a powder gas pipe, 7 is a chamber, 8 is a pump, 9 is a particle sizer, 10 is a powder collector,
11 is a particle sizer, 12 is a hydrogen gas (H 2 ) cylinder, 13 is a methane gas (CH 4 ) cylinder, 14 is a flow meter, 15 is a powder feeder, and 16 is an arc power supply.
本発明においては、好ましくは陰極及び陽極を有する
DCプラズマトーチを用いる熱プラズマCVD法によって、
陰極１と陽極２の間に放電ガスを流しながら電圧を印加
してDCアーク放電を起こさせ、5000℃以上のアークプラ
ズマを発生させる。In the present invention, it preferably has a cathode and an anode
By thermal plasma CVD method using DC plasma torch,
While applying a discharge gas between the cathode 1 and the anode 2, a voltage is applied to cause a DC arc discharge to generate an arc plasma of 5000 ° C. or more.
一方、陽極２に設けられている放電ガス配管５よりア
ークプラズマ発生部に供給された原料ガスは急速に高温
度にまで加熱されて活性化し、密度の高いラジカルを発
生し、また体積が膨張して超高速のプラズマジェット３
となって噴射する。On the other hand, the raw material gas supplied from the discharge gas pipe 5 provided in the anode 2 to the arc plasma generating section is rapidly heated to a high temperature and activated, generating radicals with high density and expanding in volume. Plasma jet 3
And fire.
本発明では、例えばH2及びCH4混合ガスのアーク放電
によって生じた温度5000℃以上のプラズマジェット３に
パウダーフィーダ15を通して、核となる微粒子を含んだ
パウダーガス４を衝突させて急冷することにより、核粒
子表面にダイヤモンドがコーティングされる。この粒子
を含む排ガスを循環させて繰り返しプラズマジェットに
衝突せしめることにより、ダイヤモンド粒子は成長して
いき、所望の大きさになったダイヤモンド粒子は分粒器
９で分粒され、粉末捕集器10に回収される。更に分粒器
11では、粒子を含まない放電ガスを作る。この方法では
原料ガス、反応生成物を循環させるため、極めて高い収
率でダイヤモンド粒子を連続的に合成できる。なお、こ
こで用いる分粒器９及び11はともに、乾式遠心分離型分
粒器などを用いることができる。特に最初の分粒器９で
は循環する粒子のうち所望のサイズのダイヤモンドを捕
集回収するために設けられたもので、例えばサイクロト
ロン式分粒器を用いることができ、逆に分粒器11では微
小サイズの粉末を除去するために、例えばアキュカット
式の分粒器と0.1μｍ程度のフィルターを組み合せたも
のを用いることができる。In the present invention, for example, the powder jet 4 containing nucleated fine particles is caused to collide with the plasma jet 3 having a temperature of 5000 ° C. or more generated by the arc discharge of the mixed gas of H 2 and CH 4 through the powder feeder 15 and rapidly cooled. Then, the core particles are coated with diamond. By circulating the exhaust gas containing the particles and repeatedly colliding with the plasma jet, the diamond particles grow, and the diamond particles having a desired size are sieved by the sizing device 9 and the powder collector 10. Will be collected. Further sizer
In step 11, a discharge gas containing no particles is produced. In this method, since the raw material gas and the reaction product are circulated, diamond particles can be continuously synthesized at an extremely high yield. It is to be noted that a dry centrifugal separator or the like can be used for both the sizers 9 and 11 used here. In particular, the first sizer 9 is provided for collecting and collecting diamond of a desired size among the circulating particles. For example, a cyclotron type sizer can be used. In order to remove fine-sized powder, for example, a combination of an Accu-cut type particle sizer and a filter of about 0.1 μm can be used.
原料ガスは水素ガス（H2）を主とし、これに炭素源と
して、炭素化合物ガス、例えば、メタンガス（CH4）を
用いる。また、必要に応じて、放電を安定化させるため
のヘリウム、アルゴン等の不活性ガスや、グラファイト
の発生をおさえるために水蒸気、更には酸素ガスや過酸
化水素ガス等の酸化性ガスを混合しても良い。The raw material gas is mainly hydrogen gas (H 2 ), and a carbon compound gas such as methane gas (CH 4 ) is used as a carbon source. In addition, if necessary, an inert gas such as helium or argon for stabilizing the discharge, or water vapor for suppressing the generation of graphite, and an oxidizing gas such as oxygen gas or hydrogen peroxide gas may be mixed. May be.
核となる微粒子は、ダイヤモンドのほかに炭化硅素
（SiC）、炭化タングステン（WC）、炭化チタン（Ti
C）、アルミナ（Al2O3）、モリブデン（Mo）等DCプラズ
マジェットCVD法によってダイヤモンドコーティングが
できる物質なら何でも良い。The fine particles that serve as nuclei are, in addition to diamond, silicon carbide (SiC), tungsten carbide (WC), titanium carbide (Ti
Any substance that can be diamond-coated by DC plasma jet CVD, such as C), alumina (Al 2 O 3 ), molybdenum (Mo), may be used.
以下に本発明の実施例を説明するが、本発明の技術的
範囲をこれらの範囲に限定するものでないことはいうま
でもない。Examples of the present invention will be described below, but it goes without saying that the technical scope of the present invention is not limited to these ranges.
実施例１ 第１図に示したような循環系装置を用いてダイヤモン
ド粒子を合成した。Example 1 Diamond particles were synthesized using a circulation system as shown in FIG.
即ち、２重量％Y2O3添加タングステンを電極としたプ
ラズマトーチを用いた装置で、放電ガス流量20/min、
パウダーガス流量20/min、メタン（CH4）濃度２容積
％アーク電流20A、アーク電圧110V、核粒子を平均粒径
0.5μｍのダイヤモンド粒子パウダーを供給量1g/hの条
件で、回収ダイヤモンド粒の粒径を50μｍとして、10時
間の連続運転を行った。なお、分粒器９は前記したサイ
クロトロン式の分粒器を用い、分粒器11はアキュカット
式の分粒器と0.1μｍのフィルターを組み合せたものを
用いた。That is, an apparatus using a plasma torch using 2 wt% Y 2 O 3 added tungsten as an electrode, discharge gas flow rate 20 / min,
The average particle diameter of the powder gas flow rate 20 / min, methane (CH 4) concentration of 2% by volume arc current 20A, arc voltage 110V, the core particles
A continuous operation for 10 hours was performed under the condition that the supply amount of diamond particles of 0.5 μm was 1 g / h and the diameter of the collected diamond particles was 50 μm. In addition, the above-mentioned cyclotron type particle sizer was used as the particle sizer 9, and the particle sizer 11 used was a combination of an Accu-cut type particle sizer and a 0.1 μm filter.
その結果、約10g/hrのダイヤモンド粒子を得ることが
できた。As a result, about 10 g / hr of diamond particles were obtained.
得られたダイヤモンド粒子の物性はＸ線回折、ラマン
分光で調べたところ、良質の立方晶ダイヤモンドが得ら
れたことが確認され、また硬度は約50μｍ径の粒子を金
属中に埋め込み、これをマイクロビッカース硬度計で調
べたところ、7000〜10000kg/mm2であった。When the physical properties of the obtained diamond particles were examined by X-ray diffraction and Raman spectroscopy, it was confirmed that high-quality cubic diamond was obtained.Moreover, particles having a hardness of about 50 μm were embedded in a metal, When examined with a Vickers hardness tester, the value was 7000 to 10,000 kg / mm 2 .
実施例２ ダイヤモンド粒子の代りにSiCを核粒子として、また
原料ガスとしてメタノールを用いた以外は、実施例１と
同様にして、第１図の装置を用いてダイヤモンド粒子を
製造した。即ち、メタノール濃度４容積％、核粒子とし
て粒径１μｍのSiCを4g/hrで供給して回収ダイヤモンド
径50μｍで連続運転し、ダイヤモンド粒子を約20g/hrの
速度で製造した。Example 2 Diamond particles were produced using the apparatus shown in FIG. 1 in the same manner as in Example 1 except that SiC was used as core particles instead of diamond particles and methanol was used as a raw material gas. That is, 4 g / hr of SiC having a methanol concentration of 4% by volume and a particle diameter of 1 μm as core particles was supplied at a rate of 4 g / hr, and a continuous operation was performed at a collected diamond diameter of 50 μm to produce diamond particles at a rate of about 20 g / hr.
本発明によれば単純な装置及び工程で、高圧を用いて
安価で連続的に高い収率でダイヤモンド粒子を合成する
ことができるため、ダイヤモンド粒子のコストを大幅に
低減させることができる。ADVANTAGE OF THE INVENTION According to this invention, since a diamond particle can be synthesize | combined with a simple apparatus and process at high yield using a high pressure and cheap, the cost of a diamond particle can be reduced sharply.
第１図は、本発明に従ったダイヤモンド粒子の製造プロ
セスを示す概略図面である。 １……陰極、２……陽極、３……プラズマジェット、４
……パウダーガス、５……放電ガス配管、６……パウダ
ーガス配管、７……チャンバー、８……ポンプ、９……
分粒器、10……粉末捕集器、11……分粒器、12……水素
ガスボンベ、13……メタンガスボンベ、14……流量計、
15……パウダーフィーダーFIG. 1 is a schematic drawing showing a process for producing diamond particles according to the present invention. 1 ... cathode, 2 ... anode, 3 ... plasma jet, 4
... powder gas, 5 ... discharge gas pipe, 6 ... powder gas pipe, 7 ... chamber, 8 ... pump, 9 ...
Particle sizer, 10: Powder collector, 11: Particle sizer, 12: Hydrogen gas cylinder, 13: Methane gas cylinder, 14: Flow meter,
15 ... Powder feeder
フロントページの続き (72)発明者 越野 長明 神奈川県川崎市中原区上小田中1015番地 富士通株式会社内 (56)参考文献 特開 平１−157497（ＪＰ，Ａ) 特開 平１−111797（ＪＰ，Ａ)Continuation of front page (72) Inventor Nagaaki Koshino 1015 Uedanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (56) References JP-A-1-157497 (JP, A) JP-A-1-111797 (JP , A)
Claims (4)
発生せしめた熱プラズマをプラズマジェットとして噴出
させ、これにダイヤモンド粒子を含むパウダーガスを噴
射させて熱プラズマを急冷させることによりダイヤモン
ド粒子の表面にダイヤモンドを気相成長させ、かつ反応
ガスを分粒器を含む循環系中を通して循環せしめること
により高い収率で、粒径の均一なダイヤモンド粒子を気
相成長させる方法。A plasma torch is used to eject thermal plasma generated by an arc discharge as a plasma jet, and a powder gas containing diamond particles is injected into the plasma jet to rapidly cool the thermal plasma, whereby the diamond particles are deposited on the surface of the diamond particles. A method for vapor-phase-growing diamond particles having a uniform particle size with a high yield by vapor-growing and reacting a reaction gas through a circulation system including a particle sizer.
むガスを活性化したものである特許請求の範囲第１項に
記載の方法。2. The method according to claim 1, wherein the thermal plasma is an activated gas containing hydrogen and gaseous hydrocarbons.
不活性ガスを含む特許請求の範囲第２項記載の方法。3. The method according to claim 2, wherein the gas comprising hydrogen and gaseous hydrocarbon further comprises an inert gas.
る特許請求の範囲第１項記載の方法。4. The method according to claim 1, wherein the temperature of the thermal plasma is a temperature of 5000 ° C. or higher.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62320141A JP2584805B2 (en) | 1987-12-19 | 1987-12-19 | Method for synthesizing diamond particles |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62320141A JP2584805B2 (en) | 1987-12-19 | 1987-12-19 | Method for synthesizing diamond particles |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01164795A JPH01164795A (en) | 1989-06-28 |
| JP2584805B2 true JP2584805B2 (en) | 1997-02-26 |
Family
ID=18118166
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62320141A Expired - Lifetime JP2584805B2 (en) | 1987-12-19 | 1987-12-19 | Method for synthesizing diamond particles |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2584805B2 (en) |
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| DE4115930C1 (en) * | 1991-05-16 | 1992-08-27 | Utp Schweissmaterial Gmbh & Co Kg, 7812 Bad Krozingen, De | |
| US5635254A (en) * | 1993-01-12 | 1997-06-03 | Martin Marietta Energy Systems, Inc. | Plasma spraying method for forming diamond and diamond-like coatings |
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| US9511352B2 (en) | 2012-11-21 | 2016-12-06 | SDCmaterials, Inc. | Three-way catalytic converter using nanoparticles |
| US9156025B2 (en) | 2012-11-21 | 2015-10-13 | SDCmaterials, Inc. | Three-way catalytic converter using nanoparticles |
| EP3024571B1 (en) | 2013-07-25 | 2020-05-27 | Umicore AG & Co. KG | Washcoats and coated substrates for catalytic converters |
| JP2016536120A (en) | 2013-10-22 | 2016-11-24 | エスディーシーマテリアルズ， インコーポレイテッド | Catalyst design for heavy duty diesel combustion engines |
| KR20160074574A (en) | 2013-10-22 | 2016-06-28 | 에스디씨머티리얼스, 인코포레이티드 | COMPOSITIONS OF LEAN NOx TRAP |
| WO2015143225A1 (en) | 2014-03-21 | 2015-09-24 | SDCmaterials, Inc. | Compositions for passive nox adsorption (pna) systems |
| US9969620B2 (en) * | 2014-03-31 | 2018-05-15 | Case Western Reserve University | Nanoscale diamond particles and method of forming nanoscale diamond particles |
-
1987
- 1987-12-19 JP JP62320141A patent/JP2584805B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20150105901A (en) * | 2014-03-10 | 2015-09-18 | 주식회사 닛포리 설계 | Cleaning Tools |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01164795A (en) | 1989-06-28 |
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