JPH02217472A - Diamond tool member and its production - Google Patents

Abstract

PURPOSE:To produce a tool member having high hardness and wear resistance by forming an intermediate layer consisting of a metal-carbide film and a metallic film which are composed of the same metal on a member made of carbide- type sintered hard alloy and then forming a diamond film on the above intermediate layer. CONSTITUTION:A primary intermediate layer consisting of metal carbide and a secondary intermediate layer composed of the same metal as the metal of the above metal carbide are successively formed on a member made of carbide- type sintered hard alloy (WC-Co, WC-TiC-Co, etc.). Further, the metal used here is at least one kind selected from group IVa metals (Ti, etc.), group Va metals (Ta, etc.), and group VIa metals (W, etc.) of the periodic table and silicon. Subsequently, a diamond film is formed on the above intermediate layers by a thermal CVD method, a plasma CVD method, etc. By this method, the tool member on which the diamond film is formed with superior adhesive strength via the intermediate layers can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a diamond tool member and a method for manufacturing the same. More specifically, a diamond film is formed with good adhesion on a carbide cemented carbide member through an intermediate layer formed by sequentially forming a metal carbide film and a metal film made of the same metal. The present invention relates to a diamond tool member and its manufacturing method.

[Prior art and problems to be solved by the invention] Conventionally, diamond tools have been used as tools that require high hardness and wear resistance, such as cutting tools, polishing tools, dies, etc., and carbide tools, and wear-resistant tools. It is particularly preferred because of its outstanding hardness, abrasion resistance, etc.

Conventionally, diamond tools have been used in which sintered diamond or single crystal diamond is mounted on the surface of a member such as cemented carbide or high-hardness metal by brazing or the like.

On the other hand, in recent years, vapor phase diamond synthesis techniques such as CVD and PVD have been used to form a diamond film by precipitation on the surface of a base material (member) made of cemented carbide or high-hardness metal. The production of diamond-coated members made of diamond-coated members has been studied, and attempts have been made to apply them to the above-mentioned uses.

By the way, since diamond is the hardest substance, a diamond film formed on the surface of a base material (m-material) such as cemented carbide is used to impart high hardness and wear resistance to the base material (component). Protection of the coating member and the base material (member)!
It is thought that it can be effectively used as III.

For example, if a diamond film is formed on the surface of a cemented carbide base material (member) used for a carbide tool such as a cutting tool or a polishing tool, an even better carbide tool should be obtained.

However, the adhesion between the surface of cemented carbide and diamond is usually poor, and it has not been possible to obtain a tool that can be put to practical use.

Therefore, in order to improve the adhesion between the surface of the cemented carbide and diamond, a technique has been proposed in which an intermediate layer is formed between the cemented carbide and the diamond film.

For example, JP-A-58-126972 discloses that an intermediate layer made of one or more selected from carbides, nitrides, borides, and oxides of IVa, Va, and Vla group metals is first formed on the surface of a cemented carbide. However, a cemented carbide with a diamond film is described in which a diamond film is then formed on the intermediate layer.

However, in the methods described in such publications, although it is said that the adhesion is improved by providing an intermediate layer, it is not possible to improve the adhesion between the cemented carbide and the intermediate layer, and between the intermediate layer and the diamond film at the same time. There are some problems, such as it is difficult to say that it has been sufficiently improved to the standard level.

On the other hand, there is also a technology that aims to improve the adhesion between the surface of the base material (component) and diamond without forming an intermediate layer between the diamond film and the base material (component) for cemented carbide tools such as cemented carbide. Proposed.

For example, in Japanese Patent Application Laid-Open No. 63-100182, Co
A cutting tool tip made of cemented carbide with a diamond film is described, which is made by forming a diamond film on a tungsten carbide based cemented carbide made of tungsten carbide containing a specific amount of tungsten carbide and having a specific particle size.

However, even in this diamond film-coated cemented carbide cutting tool tip, it is difficult to say that the adhesion between the cemented carbide and the diamond film is at a sufficiently practical level, and there is a possibility that the adhesion between the cemented carbide and the diamond film may deteriorate. In order to improve adhesion, the Co content is reduced, which leads to a decrease in physical properties such as toughness and transverse rupture strength of the cemented carbide itself, resulting in insufficient strength as a cutting tool and insufficient durability. There were problems such as not being able to obtain the desired characteristics.

The present invention has been made based on the above circumstances.

The purpose of the present invention is to solve the above-mentioned problems, to provide excellent adhesion of diamond film, and to be used for tools and their components that require high hardness and wear resistance, such as carbide tools and wear-resistant tools. It is an object of the present invention to provide a diamond tool member having excellent durability and the like, and a method for manufacturing the same, whose life is greatly improved when the tool is used.

[Means for Solving the Problems] As a result of intensive research to solve the problems described above, the present inventor has developed a carbide-based cemented carbide base material used as a base material in conventional cemented carbide tools, etc. A diamond tool member is a diamond tool member in which a diamond film is provided on the surface of the base material by vapor phase synthesis via a specific intermediate layer using a diamond film, an intermediate layer, and the intermediate layer and the base material. It was discovered that the adhesion to a certain carbide cemented carbide was excellent and the above object could be achieved, and the present invention was completed based on this knowledge.

That is, the invention according to Claim 1 of Wood M provides a first intermediate layer made of a metal carbide and a second intermediate layer formed of the same metal as the metal carbide on the surface of a carbide cemented carbide member. Via.

A diamond tool member is characterized in that a diamond layer is formed, and in this case, the metal is at least one selected from metals of group rVa, group Va, and group VIa of the periodic table, and silicon. Preferably, it is metal (Claim 2).

In the invention according to claim 3 of the present application, after forming a first intermediate layer made of a metal carbide on the surface of a carbide-based cemented carbide member, the surface of the first intermediate layer is made of the same metal as the metal carbide. A method for manufacturing a diamond tool member, characterized in that a second intermediate layer is formed, and a diamond film is formed on the surface of the second intermediate layer by vapor phase synthesis, in which case the metal is Periodic table group IVa, V
Preferably, it is at least one metal selected from group a and group VIa metals and silicon (Claim 4).

In the present invention, the method for forming the first and second intermediate layers includes, for example, a sputtering method.

Ion blating method, plasma CVD method, thermal CVD
The law can be suitably adopted.

Among these, thermal CVD method and plasma C
This is the VD method. The reason is that when forming the first intermediate layer, free carbon in the base material is used as one of the carbon sources, so it is necessary to maintain the base material at a high temperature (approximately 800 to 1,200 degrees Celsius). It is from.

The diamond tool member according to the present invention can be applied to a conventional cemented carbide with a diamond film formed by directly forming a diamond film on a cemented carbide base material (member) or a cemented carbide base material formed by forming a diamond film directly on a cemented carbide base material (component), or a diamond tool member formed by forming a diamond film directly on a cemented carbide base material (member). The adhesion of the diamond film is superior to that of a cemented carbide with a diamond-coated intermediate layer formed by forming a diamond film on the (member).

The reason why the diamond tool member of the present invention has excellent adhesion of the diamond film and has excellent service life and durability as a tool is that the diamond film and the carbide cemented carbide member (base material) are successively bonded to each other. This is because a plurality of specific intermediate layers are provided.

In other words, since both the carbide-based cemented carbide member (base material) and the carbide film that is the first intermediate layer are carbide-based, they are easily compatible, and for example, when forming a carbide film by thermal CVD, Carbon diffusion occurs between the base material and the carbide film while accompanied by a reaction, and the diamond film and the metal film that is the second intermediate layer are separated from each other when the diamond film is formed by vapor phase synthesis. Carbide is formed with a negative concentration gradient from the surface to the inside, and furthermore, the metal carbide film of the first intermediate layer and the metal film of the second intermediate layer are made of the same type of metal, and Since it is formed continuously, there is no clear interface between each layer, and the composition structure changes gradually or continuously from a metal carbide film to a metal film. This is thought to be because high adhesion can be achieved between any layers. In particular, the metal coating is called a metal coating.

It is presumed that the film is composed of a graded metal-metal carbide composition that partially changes to carbide (particularly at a high concentration on the outside), and the carbon in the diamond film is absorbed by the metal film. It is believed that the bond is firmly bonded by penetrating the partial carbide in the surface layer, and that this allows the above-mentioned high adhesion to be achieved, which was previously unobtainable.

Therefore, the diamond tool member of the present invention can be used, for example, in cutting tools, polishing tools, etc., such as bites, dies, wire drawing dies, cutters, end mills, taps, gauges, heads of bonding tools, carbide tools, wear-resistant tools, etc. It can be suitably used as a member of various tools that require high hardness and wear resistance, and as a base material thereof.

The present invention will be explained in more detail below.

The carbide-based cemented carbide member in the inventions of claims 1 and 2 of the present application may be a member that has already been formed as a member of a cemented carbide tool, a wear-resistant tool, etc., and may be partially formed. In other words, the shape of the carbide-based cemented carbide member is not particularly limited and may be any shape. Also good.

As the carbide-based cemented carbide member in the inventions of claims 1 and 2 of the present application, various materials such as those used in conventional cemented carbide tools can be used. Among them, for example, WC-Co, WC-TiC-
Co-based, WC-TiC-TaC-Co-based, WC-TiN
-C.

A material based on WC and CO, such as a carbide cemented carbide such as a WC-TiC-TiN-Co system, or the like can be suitably used.

Here, the particle size of WC is 1% usually 0.5#Lm~10IL
WC in this particle size range.
can be suitably used.

Moreover, the content of Co is usually within the range of 3 to 30% by weight.

The above-mentioned carbide-based cemented carbide base material preferably contains excess carbon in an amount of % by weight or less, preferably 1% by weight or less. This excess carbon is contained in the first intermediate layer. It can be used as a carbon source when forming certain metal carbide films.

In the present invention, the bond between the metal carbide film and the carbide cemented carbide member can be strengthened by diffusing this excess carbon into the metal carbide film. The metal used for forming the second intermediate layer and the metal used for forming the metal coating that is the second intermediate layer are of the same type.

This metal can be made from suitable raw materials, for example by heating C.
There is no particular restriction as long as a carbide film can be formed by the VD method; however, metals such as metals in group IVa of the periodic table such as titanium, metals in group Va of the periodic table such as tantalum, metals in group Vla of the periodic table such as tungsten, and silicon are generally used. can be suitably used. Among these, titanium, tantalum, tungsten and silicon are preferred, and titanium, tungsten and silicon are particularly preferred.

Note that these metals may be used alone or in combination with
You may use more than one species in combination.

As the metal carbide, various carbides of the metals can be used, among which TiC is used.

S i C, WC, TaC, etc. are preferred, especially TiC,
SiC and WC are preferred.

In addition, these metal carbides may be used alone, as long as they are made of the same type of metal as the metal used for the metal coating, or two or more may be used in a mixture, a solid solution, and one composition. It may also be used in combination.

The metal used for the metal coating that is the second intermediate layer is the same type of metal as the metal used for the carbide coating. The metal that forms the metal film may be used alone, or two types of metals may be used.
You may use more than one species in combination.

The diamond tool member of the present invention includes the following steps: (a) forming a carbide film made of the metal carbide on the surface of the carbide-based cemented carbide member; (b) the step (a) above; Subsequently, a step of forming a metal coating made of the metal on the surface of the metal carbide coating;

(c) Synthesizing a diamond film on the surface of the metal film by vapor phase synthesis.

In step (a), various compounds and/or mixtures consisting of a metal source corresponding to the metal and a carbon source, or a mixture thereof are used as the raw material gas used to synthesize the carbide film made of the metal carbide. be able to.

Examples of the compound having both a metal source and a carbon source include alkylated products such as methylated products, ethylated products, etc. of the above-mentioned metals, and preferred among them are methylated products such as trimethylsilane. It is.

There are no particular restrictions on the compound (metal source compound) that is the metal source and does not have a carbon source in its molecule, as long as it can form the carbide film when used together with an appropriate carbon source gas. However, halides such as hydrides, chlorides, and fluorides of the metals mentioned above are usually used, specifically, for example, titanium tetrachloride, silane gas, silicon tetrachloride, tungsten hexafluoride, tungsten hexachloride,
Examples include tantalum pentachloride.

In addition, these may be used individually by 1 type, and may use 2 or more types together.

The metal source compound is preferably used in conjunction with a suitable carbon source gas.

The carbon source gas is not particularly limited as long as it can be used together with the metal source compound to form the carbide film, but it usually includes hydrocarbons including saturated hydrocarbons such as methane, ethane, and propane. can be suitably used, with methane being particularly preferred.

In addition, these may be used individually by 1 type, and may use 2 or more types together.

Further, the raw material gas used in step (a) can be a mixed gas with an appropriate active gas such as hydrogen or an inert gas, or can be used as a carrier gas.

As this inert gas, those described below can be used.

As a specific example of this raw material gas (reactive gas), when synthesizing a carbide film made of TiC, for example,
i When synthesizing a carbide film made of a mixed gas of C1a, CH, and H2, and SiC, for example, @S
i I (4 and CH4 or Si)! < and CH4 and H2
When synthesizing a carbide film consisting of WC, @WFs and CH4 or WF, CHa and H2
Mixed gases with and the like can be suitably used.

The carbide film is formed by, for example, employing a 5CvD method, by flowing the raw material gas together with the carrier gas onto a desired surface of the carbide-based cemented carbide member to cause contact and reaction. be able to.

The reaction pressure in this thermal CVD method is usually
10-" to 760To0""preferably 1 to 100To
The reaction temperature, which is suitable to be within the range of rr, cannot be uniformly defined because it varies depending on the type and composition of the raw material gas (reactant gas) used, but 1Usually, 11
00 to 1.20 (within the range of 1°C, preferably l, (1(
It is appropriate to set the temperature to 10±100°C. In addition, when using, for example, the mixed gas of (1) above as the raw material gas (reaction gas), the reaction temperature is usually 900 to 1.100°C.
It is preferable to set it within the range of . Further, this reaction temperature, including the reaction temperature during the formation of the metal coating in step (b), is preferably controlled to an appropriate temperature mode as described later.

The step (b) is performed subsequent to the step (a),
In this step (b), the raw material gas used as a metal source for the metal coating is a metal source that is made of the same type of metal as the metal source gas used in the step (a) and that does not substantially contain carbon. can be used.

Here, from the point of efficiently performing step (a) and step (b) successively, in the step (a), the metal source and the carbon source are used as separate gases, and the raw material obtained by mixing them is used. When using a gas and taking over from step (a) to step (b), it is preferable to stop the supply of only the carbon source gas and switch to a metal source gas that does not substantially contain a carbon source or a metal source gas-containing gas. It is.

Specifically, for example, in step (a), the above
It is preferable to use a mixed gas of , [phase] or @, and only stop the supply of CH4 when proceeding to step (b).

The metal coating is formed in the step (b) under the conditions of the thermal CVD method.
The carbide film can be formed by flowing the raw material gas together with the carrier gas onto a desired surface of the carbide film formed in step (a) to cause contact and reaction.

In the MCVD method of step (b), the reaction pressure is usually 1, 10-” to 760 Torr, preferably 1
The reaction temperature, which is suitably within the range of ~100 Torr, cannot be unconditionally defined because it varies depending on the type and composition of the raw material gas (reactant gas) used, but it is usually used in step (a). It is appropriate to set the temperature to be lower than the above temperature, preferably about 200°C. In this way, by setting the temperature lower than that in step (a),
This is due to carbon diffusion from the diamond film side to the metal film when a diamond film is later formed on the surface of the metal film. Sufficient metal can be left in the surface layer of the metal coating to more effectively form metal carbides, and as a result, the bond between the diamond film and the metal coating can be more effectively strengthened. .

In addition, the reaction temperature in step (b) includes the reaction temperature in step (a), and if step (C) is performed consecutively to step (b), it also includes the reaction temperature in this step (C). , it is better to control it to an appropriate mode.

As the mode of reaction temperature etc. from step (a) to step (b), for example, as illustrated in FIG.
Step a) is carried out at a reaction temperature T,, 'C, and then step (b) is started by stopping only the supply of carbon source gas at this temperature, and at the same time the reaction temperature is lowered from 781°C to T, for example, about 200°C lower than this. .

It is preferable to use a method in which the temperature is continuously lowered to T.degree. C., and then the step (b) is continued while maintaining the temperature at T. Step (b) when performing step (c) subsequent to step (b)
Also shown is an example of a suitable mode of reaction temperature from step (C) to step (C). That is, in step (b), the reaction temperature T is set to substantially ensure the thickness of the metal coating.
−* 'c, then the reaction temperature was changed from 10°C to a reaction temperature T suitable for the synthesis of the diamond film described later, "c
When the temperature is increased to 2 and the temperature becomes substantially 11°C,
The raw material gas is changed to one suitable for diamond film synthesis described later, and the diamond film synthesis process, that is, step (C
) or a similar method can be suitably adopted.

In the diamond tool member of the present invention, the thicknesses of the carbide film and the metal film are determined because the interface between the respective layers is not sharp.

Although it is difficult to define it clearly, it is appropriate that the thickness of the carbide film is usually within the range of about 0.1 = 10 pm, preferably about 0.2 to 5#L111; The thickness of the metal coating is usually 0.05 to 1.
It is appropriate to set it within the range of about 5 #Lm, preferably about 0.1 S-1 m.

If the thickness of this carbide film is too small, the desired effect of the intermediate layer may not be achieved; on the other hand, if it is too thick, the strength within the intermediate layer may not be sufficient, leading to a decrease in adhesion. There is. Similarly, if the thickness of the metal coating is too small, the desired effect of the intermediate layer may not be achieved, and if it is too large, the strength within the intermediate layer may not be sufficient, or the process ( In C), the metal coating may not be sufficiently carbonized, leading to a decrease in adhesion.

Next, the diamond film and its formation process will be explained in detail.

The diamond tool member of the present invention can be obtained by forming a diamond film by vapor phase synthesis on a desired surface of the metal coating formed in step (b). This diamond film synthesis step, that is, the step (
It is usually preferable to carry out c) continuously following step (b) from the viewpoint of process efficiency, but the method is not necessarily limited to this.

In the diamond tool member of the present invention, the thickness of the diamond film is not strictly determined due to the difficulty in determining a clear interface between the diamond film and the underlying metal film as described above. Although it cannot be specified, it is usually 0.1 to 1004
It is appropriate to set it to about m, preferably about 0.2 to ffOpm.

If this diamond film is too thin, it may not be able to sufficiently cover the surface of a given metal coating;
If the thickness of the diamond film is too large, the diamond film may peel off.

In the present invention, the term "diamond" includes, in addition to diamond, diamond that partially contains diamond-like carbon and diamond-like carbon.

As the carbon source compound (carbon source gas) used when forming the diamond film, various compounds such as those commonly used can be used.

Examples of this carbon source gas include methane.

Paraffinic hydrocarbons such as ethane, propane, butane;
Olefinic hydrocarbons such as ethylene, propylene, and butylene; Acetylenic hydrocarbons such as acetylene and arylene; Diolefinic hydrocarbons such as butadiene and allene; Alicyclic hydrocarbons such as cyclopropane, cyclobutane, cyclopentane, and cyclohexane; Aromatic hydrocarbons such as cyclobutadiene, benzene, toluene, xylene, and naphthalene; Ketones such as acetone, diethyl ketone, and benzophenone; Alcohols such as methanol and ethanol;
Other oxygen-containing hydrocarbons; Amines such as trimethylamine and triethylamine; Other nitrogen-containing hydrocarbons;
Carbon dioxide, - carbon oxide.

Carbon peroxide: In addition, although not a single substance, Fire Service Act hazardous materials class 4 and class 1 such as gasoline, class 2 petroleum such as kerosene, turpentine, and camphor oil, class 3 petroleum such as heavy oil, Quaternary petroleum oils such as gear oil and cylinder oil can also be used. It is also possible to use a mixture of the various carbon compounds mentioned above.

Among these, preferred are paraffinic hydrocarbons such as methane, ethane, and propane, ketones such as acetone and benzophenone, amines such as trimethylamine and triethylamine, carbon dioxide, and carbon oxide, and the most preferred are monoxide. It is carbon.

In addition, these may be used alone, or two or more may be used in combination as a mixed gas, etc., and these may be used with active gases such as hydrogen or inert gases such as helium, argon, neon, xenon, nitrogen, etc. It may be used in combination with.

When the raw material gas contains methane gas (C1,).

Preferably, the content of methane gas is less than 1 mol%.

Moreover, -carbon oxide is particularly preferable because -carbon oxide is 1
Since a diamond film can be synthesized using a raw material gas having a high concentration of ~80 mol%, the carbonization reaction can be effectively progressed from the surface layer of the metal film to a deeper level, and the metal film and diamond This is because the adhesion to the film can be further improved.

In addition, when using carbon monoxide as a suitable carbon source gas, - it is preferable to combine carbon oxide and hydrogen gas, - jX source gas that is a combination of carbon oxide and hydrogen gas, The growth rate is fast (for example, under the same conditions, a diamond thin film can grow 2 to 10 times faster than when using a raw material gas that is a combination of methane and hydrogen gas).

The carbon oxide is not particularly limited, and for example, sufficiently purified generator gas or water gas obtained by hot reaction of coal, coke, etc. with air or steam can be used.

The hydrogen gas is not particularly limited and may be used, for example, in the gasification of petroleum, the transformation of natural gas, water gas, etc., the electrolysis of water,
Reaction of Iron and Steam 1. A sufficiently purified product obtained by complete gasification of coal can be used.

When using a mixed gas of hydrogen gas and carbon monoxide as a raw material gas, the content of -carbon oxide gas is usually 1 to 80
The raw material gas is prepared at a ratio of mol%, preferably 1 to 60 mol%, more preferably 10 to 60 mol%.

If the content of carbon monoxide gas in the mixed gas is less than 1 mol%, a sufficient growth rate of the diamond film may not be obtained;
If it exceeds 0 mol%, graphite may precipitate and the purity of the diamond component in the deposited diamond film may decrease.

The carbon source gas or the raw material gas containing the carbon source gas is brought into contact and reacted in an activated (excited) state by flowing it over a predetermined surface of the metal coating, usually with a suitable carrier gas, A diamond film with desired properties is formed.

As this carrier gas, the above-mentioned inert gases and, if necessary, reactive gases such as hydrogen, or mixed gases thereof can be used. Moreover, this carrier gas can also contain additive gases such as phosphorus, water vapor, and oxygen, if desired.

In the present invention, the diamond film is formed by a known method, such as a CVD method, a PVD method, a PCVD method,
Various diamond film vapor phase synthesis methods, such as methods combining these methods, can be used.

Among these, various thermal filament methods including the EACVD method, various direct current plasma CVD methods including the thermal plasma method, various high frequency plasma CVD methods including the thermal plasma method, and microwave methods including the ECR method are generally used. A plasma CVD method or the like can be suitably used. Among them,
Various plasma CVD methods are preferred, and microwave plasma CVD method is particularly preferred.

The reaction conditions for forming the diamond film are as follows:
There are no particular limitations, and reaction conditions commonly used in the above-mentioned vapor phase synthesis methods can be applied.

For example, the reaction pressure is typically 10'' to 10''To
rr, preferably within the range of IP' to 10' Torr. This reaction pressure is 10-'Tor
If it is lower than r, the formation rate of the diamond thin film may become slow. On the other hand, even if it is made higher than 10' Torr, no corresponding effect will be achieved.

The reaction temperature (temperature of the surface of the metal coating) cannot be generally defined because it varies depending on the activation means of the raw material gas, etc.; however, it is usually room temperature to 1.200°C, preferably 600 to 1.200°C, It is appropriate that the temperature be within the range of ioo°C. If this temperature is lower than room temperature, the formation of a diamond film may be insufficient; on the other hand, if it exceeds 1,700°C, the etching effect becomes significant and a diamond film may not be formed.

The reaction time is preferably set appropriately depending on the formation rate of the diamond film so that the diamond film has a desired thickness.

The diamond tool member of the present invention can be manufactured in the manner described above.

The diamond tool member of the present invention is a conventional diamond (thin)! Compared to cemented carbide with I and conventional intermediate layer type cemented carbide with a diamond film, it has particularly excellent adhesion of the diamond film, and its life as a cemented carbide tool is significantly improved. , for example, cutting tools,
Various types of tools that require high hardness and wear resistance, such as grinding tool bits, dies, wire drawing dies, cutters, end mills, taps, gauges, carbide tools such as bonding tool heads, and wear-resistant tools. It can be suitably used as a member or the like.

[Example] (Examples 1 to 6 and Comparative Examples 1 to 5) WCC containing excess carbon as a base material.

A carbide-based cemented carbide tool member (Co: 10% by weight; the remainder is WC and excess carbon, and the carbon content is WC
5.1% by weight including contents: Tool shape: 5PGN
421/round honing, Raku 0.05■ hazy; old P treated product), and using the temperature and raw material gas supply mode shown in Figure 1 on the surface, under the conditions shown below,
A carbide film, a metal film, and a diamond film were sequentially synthesized to produce a sample of a desired diamond-coated member.

■ Carbide film synthesis step [step (a)] and metal film synthesis step [step (b)]: Set the reaction temperature to the mode shown in FIG. 1 [T, , = i, oo
.

(“C), T, *-800℃, T, 3=900℃].

A carbide film and a metal film were sequentially synthesized by thermal CVD.

As the raw material gas, in step (a), a mixed gas of metal source gas (5% by volume), methane (5% by volume), and hydrogen (90% by volume) shown in Table 1 is used, and in step (b), methane is used. Only the supply was stopped.

In addition, the supply flow rate of raw material gas is 1.000sc in both processes.
cm.

The reaction time of each step and the thickness of each film obtained,
The carbonization rate of the metal coating is shown in Table 1, and the deposition rate of the carbide coating and metal coating is 4 m/hr.
and 2 m/hr.

(2) Synthesis step of diamond film [Step (C)]: A diamond film was synthesized by the microwave PCVD method at a reaction temperature of T, s -900 <``c''.

As the raw material gas, a mixed gas of -carbon oxide (20 vol) and hydrogen was used, and the total flow rate was kept at 100°C.

The reaction time, the thickness of the obtained film, and the analysis results are shown in Table 1.

Component analysis of the diamond films by Raman spectroscopy revealed that although they all contained some diamond-like carbon, they were diamond films with good crystallinity, with a sharp peak at 1333c■-1. Ta.

Note that the film formation rate was approximately 168 μm/hr.

Each of the samples obtained above was used as a cutting blade for a lathe, and a cutting test was conducted under the following conditions to evaluate performance.

An aluminum alloy containing 8% by weight of Si was used as the material to be cut, and this was machined using a lathe at a linear cutting speed of 600 s/sin, a feed rate of 0.2 mm/rev, and a depth of cut of 0.2-. ant to measure the state of wear or peeling of the diamond film during and after processing.

Ta.

The results are shown in Table 1.

Note that the x mark in the cutting time column in Table 1 indicates a state in which the diamond film on the cutting edge has worn or peeled off and the underlying metal coating is visible, and the Q mark indicates a state in which the underlying metal coating is not visible. The tool was judged to have reached the end of its life when it appeared.

From the results in Table 1, it can be seen that the life of the diamond tool member of the present invention is significantly improved compared to the conventional diamond tool member. This is due to the extremely excellent adhesion of the diamond film of the diamond tool member of the present invention.

(The following is a blank space) [Effects of the Invention] According to the present invention, since a specific intermediate layer is provided between the carbide cemented carbide base material and the diamond film, each layer is strongly bonded. , diamond film has excellent adhesion, and when used as tools and components that require high hardness and wear resistance, such as carbide tools and wear-resistant tools, diamond has extremely long lifespan and other durability. A member and a method for manufacturing the same can be provided.

[Brief explanation of the drawing]

FIG. 1 is a graph schematically showing an example of a reaction diagram (reaction temperature and raw material gas supply mode) according to a one-batch method preferably used in the manufacturing process of a diamond tool member of the present invention. The vertical axis in the figure shows the reaction temperature (solid line) and the concentration of carbon source gas in the feed gas (-dotted line) in arbitrary units, and the horizontal axis shows the reaction time, and r, ,, T
jll T113 represents 1 reactant degree ("C).

Claims (4)

[Claims] (1) A diamond layer is formed on the surface of a carbide cemented carbide member through a first intermediate layer made of metal carbide and a second intermediate layer made of the same metal as the metal carbide. A diamond tool member characterized by: (2) The diamond tool member according to claim 1, wherein the metal is at least one metal selected from metals of group IVa, group Va, and group VIa of the periodic table, and silicon. (3) After forming a first intermediate layer made of metal carbide on the surface of the carbide cemented carbide member, a second intermediate layer made of the same metal as the metal carbide is formed on the surface of the first intermediate layer. A method for manufacturing a diamond tool member, characterized in that a diamond film is formed on the surface of the second intermediate layer by a vapor phase synthesis method. (4) The diamond tool member according to claim 3, wherein the metal is at least one metal selected from metals of group IVa, group Va, and group VIa of the periodic table, and silicon.