JP2005047004A - Composite high-hardness material for tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite high-hardness material for tools having a base material consisting of a CBN sintered body containing, by volume, 20% cubic boron nitride, or a base material consisting of a diamond sintered body containing 40% diamond. <P>SOLUTION: At least one hard heat-resistant film mainly consisting of at least one kind of element selected among C, N and O, Ti and Al is deposited on a part related to at least cutting. The ideal composite high-hardness material for tools has both the high hardness and the high strength (several times higher than that of cemented carbide) of the CBN sintered body or the diamond sintered body and the excellent wear resistance of the hard and heat-resistant film, and demonstrates considerably long lifetime compared with a conventional tool when used in cutting of hardened steel, rough turning of cast iron, common grinding of cast iron with aluminum alloy, etc. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a cutting tool based on a sintered body mainly composed of cubic boron nitride (CBN) (hereinafter referred to as CBN sintered body) or a sintered body mainly composed of diamond (diamond sintered body). More particularly, the present invention relates to a composite material for a tool excellent in strength and wear resistance.

A CBN sintered body is a material having the second highest hardness after diamond, and is used as a metal cutting tool because of its low reactivity with metals. CBN sintered bodies are made by sintering CBN sintered particles at high temperature and high pressure using a binder (sintering aid), and can be roughly divided into the following three types:
(1) Containing 20 to 80% by volume of CBN crystal particles, and using Ti carbide, nitride, carbonitride as binder (eg, following literature)
JP 53-77811 A

(2) Containing 80% by volume of CBN crystal particles and using Al and Co metals as binders (eg, the following documents)
Japanese Patent Publication No.52-43846

(3) Containing 95 vol-% or more of CBN crystal particles and using M ₃ B ₂ N ₄ (where M is an alkaline earth metal) as a binder (eg, the following document)
JP 59-57967

  Since these CBN sintered bodies have extremely high hardness and high thermal conductivity (excellent in high temperature strength), they are used as cutting tools for various steels. For example, type (1) CBN sintered body has Vickers hardness of 3,500-4,300 and is excellent in wear resistance and fracture resistance, so it is used for cutting high-hardness cast iron. Type (3) CBN The sintered body has a Vickers hardness of 4,000 to 4,800 and is excellent in thermal conductivity, and is used for bonding tools and the like. However, the CBN sintered body has a cleavage property and has a weak point in oxidation resistance. Therefore, when cutting difficult-to-cut materials such as transmission steel, the CBN sintered body alone has insufficient wear resistance and wear. It cannot be avoided.

In order to improve the wear resistance of the CBN sintered body, a method of coating the CBN sintered body with various wear-resistant layers such as TiN has been proposed (for example, the following documents). Further, since the hardness and oxidation resistance of the wear-resistant layer are significantly inferior to those of the CBN base material, the wear of the tool is not avoided, and a cutting tool having a practically sufficient service life has not yet been obtained.
JP-A-61-183,187, JP-A-1-96,083, JP-A-1-96,084

In particular, in cutting hard hard-to-cut materials such as hardened steel, the lack of strength and hardness of the coating layer is fatal and the effect of improving the wear resistance by coating does not appear. The TiN in the cemented carbide, (TiAl) N, TiCN, when it has been proposed a tool coated with Al ₂ O _3, or the like cutting temperature increases, the internal substrate is remarkably elastic-plastic deformation, easily peeled or destroyed In particular, it cannot be used for cutting hard hard-to-cut materials such as hardened steel.

  The diamond sintered body is harder than the CBN sintered body, and the diamond particles themselves have few cleavage planes and generally have few defects, and the particles are firmly bonded. It has the characteristics of high strength, high Young's modulus, and high strength. However, these widely-sintered diamond sintered bodies have the disadvantage that diamond is inferior in oxidation resistance and cannot be used for practical cutting because the wear resistance is remarkably reduced in cutting of iron-based materials. There is. For this reason, the present situation is that the superior characteristics of the diamond sintered body cannot be fully utilized, and the present invention is limited to cutting of non-ferrous hard materials such as aluminum.

  The object of the present invention is, for example, a hardened steel having both the high hardness and high strength of a CBN sintered body or diamond sintered body (several times compared to a cemented carbide) and the excellent wear resistance of a hard heat-resistant coating. An object of the present invention is to provide an ideal composite high-hardness material for a tool that has a remarkably long life compared to conventional tools when used in cutting, rough cutting of cast iron, co-machining of cast iron and aluminum alloy, and the like.

  The present invention relates to a composite high hardness material for a tool having a base material made of a CBN sintered body containing 20% by volume or more of cubic boron nitride or a base material made of a diamond sintered body containing 40% or more of diamond. , Having at least one hard heat-resistant film having a thickness of 0.5 to 15 μm mainly composed of at least one element selected from N and O, Ti, and Al at least in a part involved in cutting A composite high-hardness material for a tool is provided.

  The composite high hardness material for tools of the present invention is obtained by coating a CBN sintered body having excellent strength, hardness and toughness and a hard heat resistant coating having excellent hardness and heat resistance on a diamond sintered body with good adhesion. It becomes a composite high hardness material for tools having both strength, toughness and wear resistance, and has an effect of exhibiting cutting performance applicable to a wide range of applications with a significantly longer life than conventional tools.

[FIG. 1] is a conceptual diagram of the composite hardness material of the present invention, (1) is a hard heat-resistant coating, (2) is a substrate, and (3) and (4) are intermediate layers provided as necessary. And the surface layer.
[FIG. 2] is a conceptual diagram of an example of a film forming apparatus that can be used to manufacture the composite hardness material of the present invention. (5) is attached to a vacuum chamber and (6) is attached to a rotary substrate holder. (7) is a rotary base material holder, and (8) is a plurality of targets surrounding the rotary base material holder.

  The hard heat-resistant coating (1) can be formed by a PVD method such as an ion plating method. The PVD method can treat the surface of the substrate while maintaining the substrate strength (abrasion resistance and fracture resistance of the substrate in the case of a tool) at a high level. In order to produce the hard heat-resistant film of the present invention, the ionization efficiency of the raw material elements is high, the reactivity is high, and an arc type ion plate capable of obtaining a film having excellent adhesion by applying a bias voltage to the substrate. Tengu method is most suitable.

  It is preferable to provide at least one intermediate layer (3) having a thickness of 0.05 to 5 μm between the substrate (2) and the hard heat-resistant coating (1). This intermediate layer (3) is preferably made of a material selected from the group consisting of nitrides, carbides, oxides and their solid solutions of the elements 4a, 5a and 6a of the periodic table. This intermediate layer (3) serves to improve the adhesion between the hard heat resistant coating (1) and the substrate (2). In addition, by providing an intermediate layer having an intermediate characteristic between a base material and a hard heat-resistant film having greatly different characteristics, an effect of reducing the residual stress of the film can be expected by controlling the change in the characteristic stepwise.

This hard heat-resistant coating (1) can be produced by the method described in the following document.
JP-A-2-194,159

  This hard heat-resistant coating is superior in hardness compared to TiN coating (Hv of TiN = 2,000 compared to Hv of TiN = 2,800) and excellent in oxidation resistance (as opposed to the oxidation start temperature of TiN of 700 ° C) The hard heat-resistant coating is about 1,000 ° C), but the present inventors say that the cutting performance, wear resistance and fracture resistance are remarkably improved when the CBN sintered body and diamond sintered body are coated with this hard heat-resistant coating. I found out.

That is, in a cemented carbide tool, it is common to extend the life by coating with a coating of TiN, TiCN or Al ₂ O ₃ to improve wear resistance and oxidation resistance. Thus, attempts have been made to coat similar coatings on cBN tools, but with insufficient results.

The inventors of the present invention have found that an effect of extending the life of a cBN tool can be obtained by forming the constituent elements of the film with at least one of C, N, and O, Ti, and Al (wear resistance). , Oxidation resistance, reaction resistance, chipping resistance, etc.). In particular, Ti _X Al _1-X N (x = 0.3 to 0.5) is desirable because it is excellent in film characteristics (film hardness, oxidation resistance) and productivity.
Although TiAlN is known to have high hardness and high oxidation resistance, the present inventors have found that TiAlN improves oxidation resistance without impairing the wear resistance of cBN having high hardness. . Moreover, the film | membrane which added C to TiAlN is higher hardness than TiAlN, and the film | membrane which added O is excellent in oxidation resistance.
A hard heat-resistant coating having a cubic crystal structure is particularly excellent in hardness and does not impair the wear resistance of the cBN tool.

  It is generally known that the hardness of a thin film is easily influenced by the hardness of the base material, and as the thickness of the thin film becomes thin, the effect becomes remarkable and approaches the hardness of the base material. Diamond sintered body (Hv = 9000 or more at room temperature) having the highest hardness at room temperature and high temperature (800 ° C or higher) during cutting, followed by a CBN sintered body having high hardness (at room temperature) Hv = 3000 to 4500) as a base material, the deformation of the base material, which has been a major problem when using cemented carbide (Hv = 1800) as the base material, is remarkably suppressed, and high temperature conditions during cutting It has been found that the hard heat-resistant film maintains a high hardness even underneath and significantly improves the wear resistance of a tool made of a CBN sintered body and a diamond sintered body. Also, by forming a hard heat-resistant film with excellent adhesion to the substrate using the ion plating method, deformation of the hard heat-resistant film during cutting is constrained by the interface with the substrate, and the effect is also hard. The hardness of the heat resistant coating is significantly increased.

  Therefore, by coating such a hard heat-resistant coating on the surface of at least a part involved in cutting of a tool based on a CBN sintered body and a diamond sintered body, the CBN sintered body and the diamond sintered body are coated. The advantages of high hardness and high strength, and excellent heat resistance and oxidation resistance of hard heat-resistant coatings become obvious, and wear resistance and fracture resistance are remarkably improved, resulting in a significant increase in cutting performance and tool life. The effect is obtained.

  The hard heat-resistant film may have a structure in which two or more compound layers having different compositions are laminated, or a structure in which a large number of them are periodically laminated. Further, the composition of the hard heat-resistant film may be a gradient composition in which the composition changes continuously or stepwise from the substrate side to the surface side. Further, the same inclined structure can be formed between the base material and the intermediate layer or the hard heat resistant film, between the intermediate layer and the hard heat resistant film, between the hard heat resistant film, and between the hard heat resistant film and the surface layer. This inclined structure is effective when peeling or cracking of the film becomes a problem.

  When the total film thickness of the hard heat-resistant coating is less than 0.5 μm, there is almost no improvement in wear resistance, and when it exceeds 15 μm, the adhesion to the substrate decreases due to the residual stress in the hard heat-resistant coating. The effect of increasing the hardness of the hard heat-resistant film when using a high-hardness base material is diminished, the hardness of the hard heat-resistant film itself (Hv = 2800) becomes dominant, and sufficient hardness cannot be obtained. descend. Therefore, the film thickness of the entire hard heat resistant coating is 0.5 to 15 μm.

  If the thickness of the intermediate layer is less than 0.05 μm, no improvement in adhesion is observed, and conversely, if the thickness exceeds 5 μm, no improvement in adhesion is observed. Therefore, the thickness of the intermediate layer is preferably in the range of 0.05 to 5 μm from the viewpoints of characteristics and productivity. The thickness of the surface layer that can be formed on the uppermost layer of the hard heat-resistant film is preferably 5 μm or less. If it exceeds 5 μm, no improvement in wear resistance and chipping resistance is observed due to peeling or the like. Further, it is not appropriate from the viewpoint of productivity.

  The composite material for a tool of the present invention can be used after being processed into a cutting tool such as a tip, a drill or an end mill. It has been confirmed that the cutting performance and tool life of the tool made from the composite high hardness material for tool of the present invention are remarkably improved.

The CBN sintered body substrate can be selected from the above-mentioned three types of CBN sintered bodies. As preferable CBN sintered bodies, the following (1) to (3) can be raised.
(1) A sintered body obtained by ultra-high pressure sintering of cubic boron nitride (CBN) powder 30 to 90% by volume and the remaining binder powder, the remaining binder being a periodic table 4a A binder composed of at least one selected from the group consisting of nitrides, carbides, borides, oxides and solid solutions of elements 5a and 6a, and aluminum and / or aluminum compounds; A CBN sintered body which is an impurity.

  Among the CBN sintered bodies of type (1), the binder powder is selected from the group consisting of 50 to 95% by weight of TiC, TiN, TiCN, (TiM) C, (TiM) N and (TiM) CN. At least one (wherein M is a transition metal selected from the group consisting of elements 4a, 5a and 6a of the periodic table excluding Ti) and 5 to 50% by weight of aluminum and / or aluminum compound And a CBN sintered body made of unavoidable impurities is preferable because of its excellent wear resistance and strength.

(2) A sintered body obtained by ultra-high pressure sintering of cubic boron nitride (CBN) powder 40 to 95% by volume and the remaining binder powder, the remaining binder powder being 1 to 50 What consists of at least 1 sort (s) selected from the group which consists of weight percent TiN, Co, Ni, and WC, aluminum and / or an aluminum compound, and an unavoidable impurity.

(3) A sintered body obtained by ultra-high pressure sintering of 90% by volume of cubic boron nitride (CBN) powder and the remaining binder powder, and the remaining binder powder is a periodic table 1a, 2a A sintered body comprising a boride of a group element, TiN, and inevitable impurities. The remaining binder preferably contains 1 to 50% by weight of TiN.

The CBN sintered body of type (1) is known per se, and its characteristics and production methods are described in detail in the following documents.
Japanese Patent Laid-Open No. 53-7781

The CBN sintered body of type (2) can be obtained by adding TiN to the binder described in the following document.
Japanese Patent Publication No.52-43846

By adding TiN, there is adhesion with a hard heat-resistant coating. The CBN sintered body of type (3) can be obtained by adding TiN to the binder described in the following document.
JP 59-57967

  Type (3) CBN sintered body also improves adhesion to the hard heat-resistant film by adding TiN.

The CBN sintered body of type (1) is at least one selected from the group consisting of nitrides, carbides, borides, oxides, and solid solutions of group 4a, 5a, and 6a elements as a binder. And aluminum and / or aluminium compound of 5 to 50% by weight, and these react with CBN during sintering under high temperature and high pressure to form compounds such as aluminum boride (AlB ₂ ) and aluminum nitride (AlN) Is generated at the interface between the CBN particles and the binder, increasing the bonding force between the particles and improving the toughness and strength of the sintered body. When TiN and / or TiC is used as the binder, the Z values of TiN _Z and TiC _Z are 0.5 ≦ z ≦ 0.85 and 0.65 ≦ z ≦ 0.85, respectively, and the amount of free titanium is shifted from the stoichiometric ratio. Due to the effect of promoting the reaction of CBN by increasing CBN, a reaction product such as AlB ₂ , AlN, TiB ₂ can be used to obtain a CBN sintered body having better friction characteristics and strength. When the Z value is less than 0.5 and 0.65, respectively, the powder filling operation becomes difficult due to the heat generated by the oxidation reaction. When the Z value exceeds 0.85, the reactivity between CBN and the binder is almost the same as when using stoichiometric TiN and TiC. It will not change.

When TiN _Z (0.5 ≦ Z ≦ 0.85) and / or TiC _Z (0.65 ≦ Z ≦ 0.85) is used as the binder powder of the CBN sintered body of type (1), aluminum in the binder and / or When the amount of the aluminum compound is less than 5% by weight, the reaction between aluminum and / or the aluminum compound and CBN becomes insufficient, and the holding power of CBN by the binder becomes weak. On the contrary, if it exceeds 40% by weight, reaction products such as AlB ₂ , AlN, TiB _{2 and the} like increase and the retention of CBN increases, but the relative strength of CBN superior in hardness and mechanical strength compared to AlB ₂ and AlN. Since the general content is reduced, the wear resistance is significantly reduced. Therefore, conventionally, when a CBN sintered body of type (1) is used as a cutting tool, the composition of the binder powder is 60 to 95% by weight of TiN _Z (0.5 ≦ z ≦ 0.85) and / or TiC _Z ( 0.65 ≦ z ≦ 0.85), 5 to 40% by weight of aluminum and / or aluminum compound, and unavoidable impurities are most suitable.

  However, in the composite high-hardness material for tool of the present invention, excellent wear resistance is imparted to the CBN sintered body having poor wear resistance by coating a hard heat-resistant film having high hardness and excellent oxidation resistance. Therefore, it is more important than the wear resistance that the characteristics required for the CBN sintered body for base material of the composite high hardness material for tools of the present invention are high toughness and high strength. In other words, a binder powder containing a large amount of aluminum and / or an aluminum compound, which has not been used for cutting hard-to-cut materials with high hardness due to defects in wear resistance even though it has sufficient toughness in the past. It has been clarified by the present invention that even a CBN sintered body can be an ideal composite high hardness material for tools having both fracture resistance and wear resistance by coating a hard heat resistant coating.

Especially in the type (1) CBN sintered body, the remaining binder powder is inevitable with 50 to 80% by weight of TiN _Z (0.5 ≦ z ≦ 0.85) and 15 to 50% by weight of aluminum and / or aluminum compound. It consists of impurities and has a bending strength (measured in accordance with JIS standards) of 110 kgf / mm ² or more, TiC _Z (0.65 ≦ z ≦ 0.85) with a balance binder powder of 50-80 wt%, and 20-50 wt. % Of aluminum and / or aluminum compound and inevitable impurities, and the above-mentioned effect is remarkable when the bending strength (specified by JIS standard) is 105 kgf / mm ² or more. In addition, it is possible to realize a tool life sufficiently satisfying the practical level even in the hard interrupted cutting of high hardness hardened steel, which could not be cut with a CBN sintered body tool having a conventional wear resistant coating.

However, when TiN _Z (0.5 ≦ z ≦ 0.85) and / or TiC _Z (0.65 ≦ z ≦ 0.85) is used as the binder powder, if the aluminum and / or aluminum compound exceeds 50 wt%, the CBN sintered body Hardness and strength are insufficient, and it is unsuitable as a base material for the composite high hardness material for tools of the present invention.

With the type (2) CBN sintered body, a CBN sintered body having a bending strength of 105 kgf / mm ² or more can be produced by using a CBN powder having an average particle size of 3 μm or less as a starting material. High hardness hardened steel that could not be cut with a conventional CBN sintered body tool or a conventional CBN sintered body tool with a wear-resistant layer coating by coating a hard heat-resistant coating with a CBN sintered body of The tool life that satisfies the practical level can be realized even in the heavy interrupted cutting.

The diamond sintered compact substrate can be selected from the above three types. Preferred diamond sintered bodies include the following (1) to (3):
(1) A sintered body containing 50 to 98% by volume of diamond, preferably a sintered body in which the balance of the sintered body is composed of an iron group metal, WC and inevitable impurities, and a sintered body in which the iron group metal is Co preferable.

(2) A sintered body containing 60 to 95% by volume of diamond, the balance of the sintered body being at least selected from iron group metals, carbides of group 4a, 5a, and 6a elements and carbonitrides More preferably, the sintered body is composed of one type, WC, and inevitable impurities, and the iron group metal is Co and includes TiC and WC.

(3) A sintered body containing 60 to 98% by volume of diamond, the balance of which is made of silicon carbide, silicon, WC, and unavoidable impurities.
The diamond sintered body has particularly high strength among the known diamond sintered bodies, and includes one or more of iron group metals or carbides, carbonitrides, silicon carbides and silicons of elements of the periodic groups 4a, 5a and 6a. It is out. These elements have the effect of firmly bonding the substrate and the ultrathin film stack.

In the case of a diamond sintered body, it has both toughness and wear resistance by using a diamond sintered body with a bending strength (measured according to JIS standards) of 150 kgf / mm ² or more as a base material and covering it with a hard heat-resistant coating. The composite material for a tool of the present invention can also be used, and thereby a tool life sufficiently satisfying a practical level can be achieved even in a hard interrupted cutting of high hardness hardened steel, which could not be cut with a normal diamond sintered body tool. Can be realized.

Examples of the present invention will be described below, but the present invention is not limited to the following examples.
Example 1
TiN and aluminum were mixed at a weight ratio of 80:20 using cemented carbide pits and balls to obtain a binder powder. Next, this binder and cBN powder were blended in a volume ratio of 40:60, filled in a Mo container, and sintered at a pressure of 50 kb and a temperature of 1,450 ° C. for 20 minutes. After processing this sintered body into the shape of a cutting tool tip (SNGN120408), the part involved in cutting of the tip is subjected to ion plating by vacuum arc discharge using the film forming apparatus shown in FIG. A hard heat-resistant film was coated.

That is, a plurality of targets were arranged in the film forming apparatus shown in FIG. 2, and the chip was mounted on a rotary base material holder provided at the center of these targets to form a film. A TiAl target was used as the target. First, the film forming apparatus was depressurized to a vacuum of 10 ⁻⁵ Torr, Ar gas was introduced, and the chip was cleaned by applying a voltage of −1,000 V to the chip in an atmosphere of 10 ⁻² Torr. Next, after heating to 500 ° C. and exhausting Ar gas, N ₂ gas was introduced as a reaction gas at a rate of 300 cc / min, a voltage of −200 V was applied to the chip, and an arc current of 100 A was applied by vacuum arc discharge. The TiAl target was coated by evaporation ionization. The film thickness was controlled by the coating time. The ratio of Ti and Al in the compound film was adjusted by the ratio of Ti and Al in the TiAl alloy.

In the case of a film containing C and O, N ₂ , C ₂ H ₂ , and O ₂ were used as reaction gases, and the ratios of the respective flow rates were adjusted to adjust the ratios of C, N, and O. Moreover, the product which has an intermediate | middle layer and a surface layer added and arrange | positioned Ti target as a TiAl target, and formed into a film sequentially in the same way as the above.

For comparison, a coating cutting tip (1-29 to 32), which is a conventional method, was also prepared. Samples 1-29 to 32 are hard coating layers in which TiN and TiCN are used alone or in combination on the surface of a cutting tip having the same composition and shape as described above by an ion plating method using vacuum arc discharge using a normal film forming apparatus. Sample 1-33 was manufactured by forming a hard coating layer combining TiN and Al ₂ O ₃ on the surface of a cutting tip having the same composition and shape as described above by a normal CVD method. Is.
[Table 1] to [Table 4] summarize the product configuration and results.

The following cutting tests were performed using the obtained cutting tips.
As a work material, a round bar of SUJ2 material having a hardness of HRC63 was used. The outer periphery of this work material was cut at a cutting speed of 100 m / min, a cutting depth of 0.2 mm, a feed of 0.1 mm / rev, and dry for 40 minutes to obtain cutting results. The results are summarized in [Table 5].

Example 2
The CBN sintered body of the substrate was replaced with the CBN content (% by volume) and the composition (% by weight) of the binder shown in Table 6 to Table 7. When the sintered body obtained by the same sintering method as in Example 1 was analyzed by X-ray diffraction, α-Al ₂ O ₃ , WC and Co were detected as inevitable impurities.

After processing each CBN sintered body shown in [Table 6] to [Table 7] into the shape of a chip for a cutting tool, the same film forming operation as that in Example 1 was performed on the part involved in the cutting, and a vacuum arc was performed. In the same manner as Sample 1-9, an intermediate layer (TiN) was formed to a thickness of 0.5 μm, a hard heat-resistant film ((Ti _0.3 Al _0.7 ) N) was formed to a thickness of 5.6 μm, and the surface layer ( Ti (C _0.5 N _0.5 )) was coated by 0.2 μm.

The following cutting test was performed using the obtained cutting tip and a comparative cutting tip not coated with a hard heat-resistant coating.
The results are summarized in [Table 8]. The time to defect described in [Table 8] is a round bar made of heat-treated SKD11 material with four U-shaped grooves on the outer circumference to a hardness of HRC56, and the cutting speed is 100 m / min. 0.2mm, feed 0.1mm / rev, the time until chipping occurs when dry cutting.

Example 3
The same operation as in Example 1 was repeated, but in this example, the diamond content and the composition of the remaining binder were changed to those shown in [Table 9]. The material powder was mixed using a mortar, filled in a Mo container, and sintered at a pressure of 55 kb and a temperature of 1,500 ° C. for 30 minutes. Next, TiN was blended so that the volume ratio was 95: 5 and mixed using a mortar to obtain a raw material powder.

The obtained raw material powder was filled in a Mo container covered with a Co plate and sintered at a pressure of 55 kb and a temperature of 1,450 ° C. for 20 minutes. Using this sintered body, a cutting tip was prepared, and the same film formation operation as in Example 1 was performed on the part involved in the cutting, and the same intermediate layer (TiN as Sample 1-9) was formed by ion plating using vacuum arc discharge. ) Was deposited to 0.5 μm, and then the hard heat-resistant coating ((Ti _0.3 Al _0.7 ) N) was coated to 5.6 μm and the surface layer (Ti (C _0.5 N _0.5 )) was coated to 0.2 μm.

Next, for comparison with the above-mentioned cutting tip, the CBN sintered body used in Example 1 is coated with a chip coated with a hard heat-resistant film, a CBN sintered body chip not coated with a hard heat-resistant film, and a hard heat-resistant film. The following cutting test was performed using a diamond sintered body chip that was not used. Work material is FCD600 material and 16% Si-Al alloy. Combined round rods with a cutting ratio of 1: 1, cutting speed is 200m / min, cutting depth is 0.3mm, feed is 0.2mm / rev, dry type. Cut for 20 minutes.
The results are summarized in [Table 9].

It is a conceptual sectional view of the composite hardness material of the present invention, and an enlarged view in a circle. BRIEF DESCRIPTION OF THE DRAWINGS It is a conceptual diagram which shows an example of the manufacturing apparatus of the composite hardness material of this invention, (a) is conceptual sectional drawing, (b) is a conceptual top view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hard heat-resistant coating film 2 Base material 3 Intermediate | middle layer 4 Surface layer 5 Vacuum chamber 6 Base material group 7 Rotary base material holder 8 Target group
10 Cemented carbide

Claims (20)

In a composite high hardness material for a tool having a base material made of a CBN sintered body containing 20% by volume or more of cubic boron nitride or a base material made of a diamond sintered body containing 40% or more of diamond,
A tool having at least one hard heat-resistant coating composed mainly of at least one element selected from C, N, and O, Ti, and Al at least in a part involved in cutting. Composite high hardness material.   The composite high-hardness material for tools according to claim 1, wherein the hard heat-resistant film has a cubic crystal structure. The composite high-hardness material for tools according to claim 1 or 2, wherein the hard heat-resistant film has a composition represented by (Ti _X Al _1-X ) N (where 0.3 ≤ X ≤ 0.5).   The composite high-hardness material for tools according to any one of claims 1 to 3, wherein the hard heat-resistant film has a thickness of 0.5 µm or more and 15 µm or less.   At least one element selected from Group 4a, 5a, and 6a elements having a film thickness of 0.05 μm or more and 5 μm or less at the interface between the base material and the hard heat-resistant coating, and C, N, and O are selected. The composite high hardness material for tools as described in any one of Claims 1-4 which has an intermediate | middle layer of an at least 1 sort (s) of compound with an at least 1 sort (s) of element.   At least one element selected from the group 4a, 5a and 6a elements having a film thickness of 0.05 μm or more and 5 μm or less on the surface of the hard heat-resistant coating, and at least one selected from C, N and O The composite high hardness material for tools as described in any one of Claims 1-5 which has at least 1 type of compound which consists of these elements.   The base material is a sintered body obtained by ultra-high pressure sintering of cubic boron nitride (CBN) powder 30 to 90% by volume and the remaining binder powder, and the remaining binder is a periodic table 4a. A binding material consisting of at least one selected from the group consisting of nitrides, carbides, borides, oxides and solid solutions of elements 5a and 6a and aluminum and / or aluminum compounds; It is an impurity, The composite high-hardness material for tools as described in any one of Claims 1-6.   The remaining binder is 50 to 95% by weight of TiC, TiN, (TiM) C, (TiM) N and (TiM) CN (where M is a group of elements in the periodic table 4a, 5a and 6a excluding Ti). The composite high-hardness material for tools according to claim 7, comprising at least one selected from the group consisting of transition metals selected from the group consisting of 5 to 50% by weight of aluminum and / or aluminum compounds. The balance binder powder is 50-80 wt% TiN _Z (where 0.5 ≦ z ≦ 0.85), 15-50 wt% aluminum and / or aluminum compound,
The composite high-hardness material for a tool according to claim 8, which is composed of inevitable impurities and has a bending strength (measured in accordance with JIS standards) of 110 kgf / mm ² or more. The remaining binder powder is 50-80 wt% TiC _Z (z is 0.65 ≦ z ≦ 0.85), 20-50 wt% aluminum and / or aluminum compound,
The composite high-hardness material for a tool according to claim 8, which is composed of inevitable impurities and has a bending strength (measured in accordance with JIS standards) of 105 kgf / mm ² or more.   The base material is a sintered body obtained by ultra-high pressure sintering of cubic boron nitride (CBN) powder 45 to 95% by volume and the remaining binder powder, and the remaining binder powder is Co, Ni, WC, 7. The tool according to claim 1, comprising at least one selected from the group consisting of TiN, TiC, and solid solutions thereof, aluminum and / or an aluminum compound, and unavoidable impurities. Composite high hardness material.   The balance binder comprises 1 to 50% by weight of TiN, at least one selected from the group consisting of Co, Ni and WC, aluminum and / or an aluminum compound, and unavoidable impurities. The composite high hardness material for the tool described. 13. The composite high-hardness material for a tool according to claim 11 or 12, having an average particle diameter of 3 μm or less and a bending strength (measured in accordance with JIS standards) of 105 gf / mm ² or more.   The base material is a sintered body obtained by subjecting 90% by volume of cubic boron nitride (CBN) powder and the remaining binder powder to ultrahigh pressure, and the remaining binder is composed of elements 1a and 2a of the periodic table. The composite high hardness material for a tool according to any one of claims 1 to 6, comprising a boride, TiN, and inevitable impurities.   15. The composite high hardness material for a tool according to claim 14, wherein the remaining binder contains 1 to 50% by weight of TiN and a boride of the periodic table 1a or 2a group element.   The base material is a sintered body obtained by ultra-high pressure sintering of 50 to 98% by volume of diamond powder and the remaining binder powder, and the remaining binder powder is an iron group metal, WC, and unavoidable impurities. The composite high hardness material for tools as described in any one of Claims 1-6 consisting of these.   The base material is a sintered body obtained by ultra-high pressure sintering of 60 to 95% by volume of diamond powder and the remaining binder powder, and the remaining binder powder is an iron group metal and periodic table 4a, 5a. The composite high-hardness material for tools according to any one of claims 1 to 6, comprising at least one selected from carbides and carbonitrides of group 6a elements, WC, and inevitable impurities.   18. The composite high hardness material for a tool according to claim 17, wherein the remaining binder powder is made of Co, TiC, WC, and inevitable impurities.   The base material is a sintered body obtained by ultra-high pressure sintered body of diamond powder 60 to 98% by volume and binder powder, and the remaining binder powder is silicon carbide, silicon, WC, unavoidable impurities The material according to claim 1, comprising: The composite high-hardness material for tools according to any one of claims 16 to 19, which has a bending strength of 150 kgf / mm ² or more.

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