JP3380294B2 - Tool with ultra-hard film and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tool with a super hard film having excellent wear resistance and a method for manufacturing the tool.

[0002]

2. Description of the Related Art Ultra-hard materials such as diamond and cubic boron nitride have hitherto been produced by a large-scale ultra-high pressure press machine. However, according to the vapor phase synthesis method, since these materials can be obtained by a simple method, ultra-hard materials such as diamond and cubic boron nitride by the vapor phase synthesis method will be used in the future.
A wide range of applications are expected (JP-A-60-5).
4995, etc.).

However, there is a problem in that the ultra-hard film has insufficient adhesion to the base material made of, for example, silicon nitride or cemented carbide, and is likely to peel off. Therefore, as a countermeasure against this, it has been proposed that a diamond film is formed on a silicon substrate, and then this diamond film is cut out and brazed to the cutting edge of the cemented carbide tool.

However, even with this method, a method for firmly brazing a diamond film and an appropriate brazing material could not be found, so that it could not be put to practical use. In addition, this method requires the production of a diamond film having a thickness of 0.1 mm or more, resulting in high costs such as equipment and power costs.

[0005]

Therefore, if these ultra-hard films can be firmly adhered to the base material, the ultra-hard films such as diamond and cubic boron nitride can be used in a wide range. Therefore, for example, industrial tools such as cutting tools for processing metals and composite materials, industrial knives such as slitter knives, various sliding parts, wear-resistant members such as guide bushes, etc. can be expected to greatly improve performance. However, in the present situation,
Since the adhesion with the base material cannot be improved as described above, tools with these ultra-hard films have not yet been put into practical use.

[0006]

As a result of repeated studies on the above problems, the present inventor found that the film thickness was 0.3 to 100 μm.
m, a super-hard film of diamond, cubic boron nitride, or the like having a surface roughness of 0.2 μm or more on the growth surface is bonded to a bonding film containing tungsten as a main component and having a thickness of 0.1 to 5 mm. The present invention has been found out that the tool body and the super-hard film can be firmly adhered to each other by brazing the tool body to the tool body through the present invention, and the present invention has been completed.

[0007] In other words, super-hard film with a tool of the present invention is created by a vapor phase synthesis method, the film thickness is 0.3~100μm, growth
A super-hard film made of diamond or cubic boron nitride having a surface roughness of 0.2 μm or more is formed by the above-mentioned formation of the super-hard film.
Created on the long side by vapor phase synthesis method, thickness 0.1-5mm
Of tungsten or a compound of tungsten and carbon, and is joined to the tool body by brazing through a joining film. Ti, Ni, Fe, Al, Co, A is formed between the bonding film and the ultra-high humidity film.
It is desirable that an intermediate film made of at least one of u, Pr, Mg, Cu, Zr, Hf, Ta, Ag, and their carbides, nitrides, and borides be interposed, and the bonding film has a superposition It is desirable that the tungsten carbide film is formed on the hard film side.

Further, the tool with an ultra-hard film of the present invention has an ultra-hard film made of diamond or cubic boron nitride on the surface of a substrate made of single crystal silicon or the like and having a film thickness of 0.3 to 1.
00μm, the surface roughness of the growth surface will be 0.2μm or more
And tungsten on the growth surface of the ultra-hard film ,
After forming a bonding film made of at least one of the compounds of tungsten and carbon by a vapor phase synthesis method, removing the base, and then bonding the bonding film to the tool body by brazing It is manufactured by attaching a film to the tool body through the bonding film. The substrate made of silicon or the like may be removed after the bonding film is bonded to the tool body by brazing . Further, after forming an ultra-hard film on the surface of the substrate, Ti, Ni, Fe, Al, Co, Au, Pr, Mg,
An intermediate film made of at least one of Cu, Zr, Hf, Ta, Ag and their carbides, nitrides and borides is formed by a conventional method such as physical vapor deposition (PVD method), and tungsten or tungsten is formed on the intermediate film. A bonding film made of a compound of tungsten and carbon may be formed. In the intermediate film, the metal may be changed into carbides, nitrides, or borides thereof by heating during CVD or brazing.

The compound of tungsten and carbon is WC
And W2C.

The surface of the ultra-hard film on the bonding film side has a surface roughness Rm.
It is important that ax is 0.2 μm or more. 0.2
This is because if it is smaller than μm, the adhesion strength of the superhard film to the bonding film becomes small and peeling of the superhard film occurs during cutting. The surface roughness Rmax is particularly preferably 1 μm or more. Such adjustment of the surface roughness can be obtained by appropriately adjusting various film-forming parameters at the time of forming the ultra-hard film.

[0011]

In the tool with an ultra-hard film of the present invention, the ultra-hard film is not directly bonded to the tool body but is bonded through a bonding film made of tungsten or a compound of tungsten and carbon prepared by a vapor phase synthesis method. Since it is joined to the tool body with the use of a tool, the joining strength between the ultra-hard film and the tool body is improved. That is, the bonding film is brazed to the tool body with a brazing material such as Ag brazing or Au—Sn, but the bonding film made of tungsten or a compound of tungsten and carbon has good wettability with the brazing material. Therefore, the bonding film and the tool body are firmly bonded to each other, and as a result, the bonding strength between the ultra-hard film and the tool body is improved.

Further, Ti, N is formed between the ultra-hard film and the bonding film.
When an intermediate film such as i or Fe is formed, the stress due to the difference in coefficient of thermal expansion between the ultra-hard film, the bonding film, and the tool body is relieved by the plastic deformation of the intermediate film, and the ultra-hard film peels off during cutting. Prevent.

When the bonding film is formed by forming a tungsten carbide film on the ultra-hard film side, the strength of the bonding film and the ultra-hard film increases due to the presence of the high-strength tungsten carbide film. The adhesiveness between the bonding film and the ultra-hard film is further improved.

Moreover, since diamond, cubic boron nitride and tungsten, or a compound of tungsten and carbon have similar coefficients of thermal expansion, film peeling can be suppressed, and the compound of tungsten or tungsten and carbon can be suppressed. Diamond and cubic boron nitride do not decompose due to the low formation temperature of.

[0015]

EXAMPLE 1 A tool with a super hard film and a method for manufacturing the same according to the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a tool with an ultra-hard film according to the present invention, and reference numeral 31 denotes a tool body composed of, for example, a slitter knife. This tool body 31 is, for example,
WC, Cobalt (Co) and Periodic Table 4a, 5a, 6a
From compounds consisting of carbides, nitrides or carbonitrides of group elements, or TiC or TiCN and nickel (Ni) or Co and carbides, nitrides or carbonitrides of group 4a, 5a or 6a of the periodic table Compound, a compound composed of silicon carbide (SiC), boron and carbon, and Si3
It is composed of a compound composed of N4 or SiC and a rare earth element oxide. Further, the tool body 31 may be made of iron-based alloy, Ni-based, Co-based alloy, high speed steel, or the like.

On the surface of the tool body 31, a bonding film 33 made of tungsten or a compound of tungsten and carbon is formed by a vapor phase synthesis method, and further, on the surface of the bonding film 33, a diamond film is formed. Alternatively, a super hard film 35 made of cubic boron nitride or the like is formed. That is, the superhard film 35 is attached to the tool body 31 via the bonding film 33 by brazing.

To produce such a tool with a super hard film, first, as shown in FIG. 2, a super hard film 35 such as diamond or cubic boron nitride (cBN) is formed on a substrate 37. Microwave Wax plasma CV for diamond film
D, hot filament method, cubic boron nitride film is Ion
Be Am Assisted Deposition
Can be created by law.

For example, in diamond, Japanese Patent Publication No. 61-
The methods disclosed in JP-B No. 25679 and JP-B No. 61-2632 are used, and for cubic boron nitride films, the methods disclosed in JP-B-5-9513 and JP-B-5-15788 are used. used. Further, the thickness of the film and the crystal structure (ratio of pure diamond or cBN) can be arbitrarily selected, but the condition that the adhesion to the substrate 37 is low is selected. Further, the surface of the super hard film 35 on the bonding film side is
It is important that the surface roughness Rmax is 0.2 μm or more
In particular , it is desirable that the thickness is 1 μm or more. The surface roughness Ra of the surface of the ultra-hard film 35 can be adjusted by changing parameters such as temperature, gas flow rate, and pressure during film formation of the ultra-hard film. The film thickness of the ultra-hard film 35 is preferably 0.3 to 100 μm in terms of the balance between performance and productivity.

The substrate 37 on which these films are formed is formed of, for example, a metal such as silicon, carbon or titanium, and can be arbitrarily selected, but the ease of nucleation at the initial stage of the film formation and the substrate in the subsequent steps are used. A substrate 37 made of silicon is suitable because it is easy to remove 37.

Next, as shown in FIG. 3, a compound consisting of tungsten (W), W and carbon (C) (as shown in FIG. 3 is formed on the ultra-hard film 35 such as diamond or cBN formed on the substrate 37. At least one of the bonding films 33) is formed. A known method can be used for the film formation. For example, describing an example of forming W, the ultra-hard film 35.
The substrate 37 to which is attached is housed in the chemical vapor deposition apparatus,
The inside of this chemical vapor phase synthesizer is maintained at a temperature of 450 to 1200 ° C., and WF ₆ + H ₂ gas mixed so that the H ₂ / WF ₆ molar ratio is 4 or more is introduced into the vapor phase impregnation apparatus. Thus, the bonding film 33 made of W is formed on the surface of the ultra-hard film 35. An inert gas such as Ar gas or He gas may be introduced together with the WF ₆ + H ₂ gas. When forming the bonding film 33 made of W and C, a gas serving as a carbon source such as methane and acetylene is introduced into the reaction furnace at the same time as the gases of H ₂ and WF ₆ . It is important that the thickness of the bonding film 33 is about 0.1 to 5 mm because of the ease of handling and the strength in the subsequent process.
It is important .

Next, the surface of the bonding film 33 is processed by polishing or the like, and then the superhard film 35 and the bonding film 33 are masked, and the substrate 37 made of silicon or the like is dissolved and removed with an acid or the like. As a result, the bonding film 33 to which the ultra-hard film 35 is attached
Is obtained. Next, this is cut into a predetermined shape with a laser and subjected to processing such as polishing. After that, as shown in FIG. 1, the bonding film 33 is brazed to the tool body 31 with silver wax or another brazing material and bonded. That is, the ultra-hard film 35 is bonded to the tool body 31 via the bonding film 33. After the brazing is finished, final processing is performed to obtain the tool with an ultra-hard film of the present invention. The substrate 37 may be removed after brazing the bonding film 33 to the tool body 31.

According to the present invention, the bonding film 33 may be formed by forming a tungsten carbide film on the ultra-hard film 35 side thereof. To form the tungsten carbide film on the ultra-hard film 35 side of the bonding film 33, for example, after forming the ultra-hard film 35, a gas that serves as a carbon source such as methane and acetylene is simultaneously supplied with WF ₆ + H ₂ gas. To form a tungsten carbide film, and then WF ₆ + H ₂ gas is introduced into the reaction furnace. By doing so, not only the strength of the multilayer film including the bonding film 33 and the superhard film 35 is increased and the performance is improved, but also the superhard film 3 such as diamond is formed.
The adhesiveness between 5 and the bonding film 33 is improved.

The bonding film 33 is formed by depositing W or a compound of W and C on an arbitrary substrate 37.
You may form the super-hard film 35 on 3. However, in this case, since the surface of the bonding film 33 formed by the vapor phase synthesis method has many irregularities, the super-hard film 35 also has many irregularities,
Limited use. When the ultra-hard film 35 is deposited on the smooth silicon substrate 37, it becomes smooth after the substrate 37 is removed, which is practically advantageous. Further, when the substrate 37 is given a predetermined shape, it is directly copied onto the superhard film 35, so that the superhard film 35 having a desired shape can be obtained.

In the above-described tool with an ultra-hard film, the ultra-hard film 35 is not directly joined to the tool body 31, but at least tungsten, a compound of tungsten and carbon prepared by a vapor phase synthesis method. Since it is bonded to the tool body 31 via the bonding film 33 made of one kind, the ultra-hard film 3
It is possible to improve the joint strength between the tool 5 and the tool body 31. When the tungsten carbide film is formed on the bonding film 33 on the ultra-hard film 35 side, the strength of the composite film including the bonding film 33 and the ultra-hard film 35 increases, and the adhesion between the bonding film 33 and the ultra-hard film 35 increases. Can be further improved.

By the way, in order to confirm the effect of the present invention, the present inventor conducted an experiment for attaching an ultra-hard film to a tool body through a bonding film made of W or a compound of W and C. Then, the brazing yield at the time of joining the joining film and the tool main body was measured, and a cutting test was performed using a tool to which an ultra-hard film was attached.

The brazing yield test is carried out by heating the brazing in argon gas for a short period of time and visually checking the completeness of the adhesion of the brazing material in the 10 tools and determining the percentage of the perfect brazing material. Went by.

In the cutting test, five tools were used to cut an aluminum-silicon alloy at a cut of 2 mm, a feed of 0.20 mm, and a cutting speed of 400 mm / min to check the peeling of the super-hard film after cutting. did. The results are shown in Table 1.

[0029]

[Table 1]

According to Table 1, the product of the present invention showed good brazing yield and good peeling after cutting.

Samples Nos. 1 and 1 are examples of coating a tool body made of cemented carbide with a cemented carbide film made of diamond. No. 2 is an example in which only the diamond film is brazed. Sample Nos. 14, 15, 17
Is an example in which the bonding film is composed of a W film and a WC film. In addition, the sample No. Nos. 16 to 18 are examples in which a titanium nitride film having a thickness of 5 μm was previously formed on the substrate and then a cBN film was formed.

Embodiment 2 In the above Embodiment 1, as shown in FIG. 4, Ti, N is deposited on the ultra-hard film 35 such as diamond or cBN.
i, Fe, Al, Co, Au, Pr, Mg, Cu, Z
An intermediate film 51 comprising at least one selected from r, Hf, Ta, Ag, and their carbides, nitrides, and borides.
Even if the bonding film 33 made of tungsten (W) or W and carbon (C) is formed on the intermediate film 51 and the bonding film 33 is brazed to the tool body 31, Although an effect similar to that of the first embodiment can be obtained, the bonding strength between the super-hard film 35 and the bonding film 33 can be further improved, and peeling of the super-hard film 35 during cutting or the like can be prevented. Further, the ultra-hard film 35, the bonding film 33, and the tool body 3
The stress due to the difference in the coefficient of thermal expansion from No. 1 is relieved by the plastic deformation of the intermediate film 51, and the super-hard film 35 at the time of cutting is reduced.
Can be prevented. The thickness of the intermediate film 51 is
0.1 to 10 μm, particularly 1 to 3 μm is preferable.

The present inventor conducted experiments to form various intermediate films between the superhard film 35 and the bonding film 33 in order to confirm the effect of the intermediate film 51. Then, the brazing yield at the time of joining the joining film and the tool body was measured, and a cutting test was performed. For the cutting test, using 5 tools, an aluminum-silicon alloy was cut at a depth of 2 mm and the feed was 0.
It was cut at 25 mm and a cutting speed of 400 mm / min, and the peeling of the superhard film after cutting was checked. The results are shown in Table 2.

[0034]

[Table 2]

Under the above cutting conditions, sample N in Table 1
o. As for No. 13, 3 out of 5 were peeled off. On the other hand, it is understood that the product of the present invention has improved brazing yield and peeling after cutting as compared with Example 1. Sample No. 40 is an example in which only the cBN film is brazed.

Example 3 In Example 1, even if the surface roughness Rmax of the bonding film side surface of the ultra-hard film 35 is 0.2 μm or more, substantially the same effect as in Example 1 can be obtained. Bonding film 33
The bonding effect between the super-hard film 35 and the bonding film 33 can be further improved by the anchor effect, and peeling of the super-hard film 35 during cutting or the like can be prevented more reliably.

The present inventor changes the film forming parameters of the super-hard film in order to confirm the bonding strength effect of the super-hard film 35 and the bonding film 33 due to the surface roughness Rmax of the surface of the super-hard film 35 on the bonding film side. Then, an experiment was performed in which the surface roughness Rmax was variously changed. Then, the brazing yield at the time of joining the joining film and the tool body was measured, and a cutting test was performed. In the cutting test, using five tools, an aluminum-silicon alloy was cut at a cut of 2 mm, a feed of 0.25 mm, and a cutting speed of 400 mm / min to check the peeling of the superhard film after cutting. The results are shown in Table 3.

[0038]

[Table 3]

Under the above cutting conditions, sample N in Table 1
o. As for 12, 3 out of 5 were peeled off. On the other hand, surface roughness Rm
It can be seen that when ax is 0.2 μm or more, peeling of the superhard film is reduced. The film thickness of the ultra-hard film was constant at 50 μm.

[0040]

As described above in detail, according to the present invention, a tool such as diamond, cubic boron nitride or the like is bonded to a tool body by bonding a super hard film to the tool body through a bonding film containing tungsten as a main component. The main body and the super-hard film can be firmly adhered to each other, the super-hard film can be used in a wide range, and a tool with a super-hard film having excellent wear resistance and toughness can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a tool with an ultra-hard film of the present invention.

FIG. 2 is a vertical cross-sectional view showing a state in which an ultra-hard film is formed on a substrate.

FIG. 3 is a vertical cross-sectional view showing a state in which a bonding film is formed on a superhard film.

FIG. 4 is a vertical cross-sectional view showing a state in which an intermediate film is formed between the ultra-hard film and the bonding film.

[Explanation of symbols]

31 Tool body 33 Bonding film 35 Ultra hard film 51 Intermediate film

Continued front page       (56) References JP-A-62-57802 (JP, A)                 JP-A-3-149140 (JP, A)                 JP-A-3-142104 (JP, A)                 JP-A-2-274405 (JP, A)                 JP 63-111104 (JP, A)                 JP-A-1-275759 (JP, A)                 Japanese Patent Publication 7-30363 (JP, B2)

Claims (5)

(57) [Claims] 1. A film formed by a vapor phase synthesis method, having a film thickness of 0.3.
An ultra-hard film made of diamond or cubic boron nitride having a surface roughness of ˜100 μm and a growth surface of 0.2 μm or more ,
Created by the vapor phase synthesis method on the growth surface of the ultra-hard film ,
A tool with an ultra-hard film, wherein the tool is joined to the tool body by brazing through a joining film made of at least one of tungsten and a compound of tungsten and carbon having a thickness of 0.1 to 5 mm . 2. Ti, N between the bonding film and the ultra-hard film.
i, Fe, Al, Co, Au, Pr, Mg, Cu, Z
The tool according to claim 1, wherein an intermediate film made of at least one of r, Hf, Ta, Ag and their carbides, nitrides, and borides is interposed. 3. The tool with an ultra-hard film according to claim 1, wherein the bonding film has a tungsten carbide film formed on the ultra-hard film side thereof. 4. The surface of a substrate made of silicon or the like has a film thickness of 0.3 to 100 μm and a growth surface having a surface roughness of 0.2 μm or more.
As shown above, an ultra-hard film made of diamond or cubic boron nitride was prepared by a vapor phase synthesis method ,
After forming a bonding film made of at least one of tungsten and a compound of tungsten and carbon to a growth surface of 0.1 to 5 mm in thickness by a vapor phase synthesis method, the substrate is removed, and then the bonding film is formed. A method for manufacturing an ultra-hard film-coated tool, characterized in that the ultra-hard film is attached to the tool body via the bonding film by joining the tool body to the tool body by brazing. 5. A substrate made of silicon or the like has a film thickness of 0.3 to 100 μm and a growth surface having a surface roughness of 0.2 μm or more.
As shown above, an ultra-hard film made of diamond or cubic boron nitride was prepared by a vapor phase synthesis method ,
A bonding film made of at least one of tungsten and a compound of tungsten and carbon is formed on the growth surface of No. 1 by a vapor phase synthesis method to a thickness of 0.1 to 5 mm, and then the bonding film is bonded to the tool body by brazing. After that, the base is removed, and the super-hard film is attached to the tool main body via the bonding film.