JPS6318050A - Cbn coating method - Google Patents

Abstract

PURPOSE:To carry out CBN coating which requires extremely high temp. and pressure at low temp. and pressure by coating a base material with an amorphous or microcrystalline BN film and projecting nitrogen ions on the film. CONSTITUTION:The surface of a base material such as a high-speed steel is coated with an amorphous or microcrystalline BN film of about 1mu thickness by reactive high frequency ion plating or high frequency sputtering. Nitrogen ions are projected on the BN film to cause a solid phase reaction and CBN is synthesized by the reaction. Thus, CBN coating is carried out.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to CBN coating, which is an ultra-hard coating applied to cutlery such as cutting tools and paper processing machines, and also to the semiconductor field. This invention relates to a CBN coating that can also be used as an insulating film.

[Conventional technology]

CBN (cubic boron nitride) II'i is an artificially synthesized compound that does not exist in nature.
DK or higher, pressure 40 Kbar or higher).

However, conventional methods can only produce powder or granules, and when using them as tools such as grinding wheels, the resin is either sintered with metal as a binder, or CBN particles are coated with a metal plating film. A method has been adopted in which the electrodeposition tool is used as an electrodeposition tool by dispersing it in the inside.

However, with these methods, (2) CBN cannot be used for precision machining due to poor dimensional accuracy since it is a particle (minimum +!1000: average particle size 5 to 6 μm); (2) CBN cannot be used as a binder; (3) Low productivity and high cost due to ultra-high temperature and high pressure treatment.

Therefore, if CBN can be coated,
In order to solve the above problems, CBN coating using various PVD (physical vapor deposition) methods is under active research, but no success has been achieved yet.

[Problem that the invention seeks to solve]

Coating is a new method of using OBM that replaces the use of particulate CBN through conventional high-temperature and high-pressure processing.
It is also said that N coating is essential.

Although methods using PVD methods, especially ion blasting and sputtering methods, are being studied for this CBN coating, a complete 0Bli coating has not yet been completed. That is, these methods B or hexagonal crystal B
These methods attempt to precipitate CBN as an Nt raw material through a gas phase reaction, but as mentioned above, CBN is synthesized through ultra-high temperature and high pressure treatment.
This is probably because synthesis is difficult due to low-temperature processing.

Furthermore, the film obtained by such a vapor phase coating method is basically a film in a non-equilibrium state and tends to become an amorphous film by nature, which is also considered to be the reason why OBM synthesis is difficult.

The present invention solves the drawbacks of the above conventional method.
It is an object of the present invention to provide a method for forming a BI coating.

[Means for solving the problems] The present invention provides a method for forming amorphous or microcrystalline BM on a base material in advance.
After coating the film, irradiate the film with nitrogen ions! This is a CBN coating method characterized by forming BN'i.

Conventional methods often result in an amorphous BN film, but the present invention utilizes the non-equilibrium energy of this amorphous film to synthesize fiCBNt by solid phase reaction. That is, an amorphous film is created by a gas phase method, and then this film is ion irradiated to cause a solid phase reaction and CBNf
t synthesis. Also, this BN contains Fe and Ni.

Addition of catalytic gold W4, such as Or, is even more advantageous because the solid phase reaction conditions are relaxed.

Furthermore, if a thick film is required, a film of the desired thickness can be obtained by repeating the method of the present invention several times.

[Effect]

Since there is a large nonequilibrium energy in an amorphous film,
Compared to normal synthesis methods, it can be processed at lower temperatures and pressures. Furthermore, according to the method of the present invention, CBN coating, which was previously impossible, becomes possible.

〔Example〕

[Experiment Example 1] High-speed steel (8KIi55) with a thickness of 30×30×5
was used as a substrate, and BM was coated on the surface by reactive high frequency ion blating and high frequency sputtering methods. The film thickness was 1 am, and the coating conditions were as follows.

1) Reactive high frequency ion brating electron gun output:
1oxvxα2m High frequency output: 6oow Bias voltage: 5oov Reaction gas (Nyi) flow rate: 12cc/min Substrate temperature
: Room temperature 2) High frequency sputtering target: 100 φ x 5 t% El purity 99 High frequency power: 300 W Atmosphere gas: Nl (20 mTorr) Substrate temperature: X-ray diffraction of each BM film obtained by the method above room temperature As a result of the analysis, no diffraction peaks were observed from any of the films.
It was amorphous.

[Experimental Example 2] In the high-frequency sputtering method described in Experimental Example 1, a composite target layer containing N1 or Fe in the t3 area ratio (BN -) Ni or BM+Fe) was used as the target, and the same conditions as the high-frequency sputtering in Experimental Example 1 were used. DeB
N + Ni and BN + Fe composite films were prepared, and their crystal structures were examined by fX-ray diffraction analysis. As a result, all films were found to be amorphous.

[Example] The four types of films created in Experimental Examples 1 and 2 were subjected to nitrogen ion irradiation treatment. The ion irradiation was an ion nitriding process using a glow discharge in nitrogen. Table 1 shows the ion nitriding conditions and the results of X-ray diffraction analysis of the film after treatment.

As a result, it became clear that all the films were made of CBN, and that by adding catalyst gold [1-], it became possible to synthesize the films at a lower temperature and under a lower accelerating voltage.

Table 1 Conditions and X-ray diffraction analysis results 1hBll: Hexagonal BN wBN: Wurtzite BN CBN: Cubic BN Note 2 v: Accelerating voltage P: N! Effects of the positive pressure invention] As detailed above in the examples, according to the method of the present invention,
CBN, which could previously only be synthesized at ultra-high temperatures and high pressures, can now be synthesized at low temperatures and low pressures. What's more, CBN, which could previously only be synthesized in granular form, can now be used in the form of a coating, which has industrial significance. It is something.

Sub-agent: 1) Akira Sub-agent Ryo Hagi Hara - Sub-agent Atsuo Yasunishi

Claims (1)

[Claims] After coating the base material with an amorphous or microcrystalline BN film, the film is irradiated with nitrogen ions to form CBN.
A CBN coating method characterized by forming.