JPS5926970A - Manufacture of diamond-hard carbide composite sintered body - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a diamond-carbide composite sintered body by sintering a mixed powder of diamond powder and hard carbide powder to which sintering aid powder is added. It is.

In the present invention, the hard carbide powder added to the diamond powder includes titanium carbide, zirconium carbide, hafnium carbide, vanadium carbide, niobium carbide, tantalum carbide, chromium carbide,
Sintering using a powder of one type of carbide selected from molybdenum carbide, tungsten carbide, boron carbide, and silicon carbide or a mixed powder of two or more types of carbides and adding it to a mixed powder of diamond powder and hard carbide powder. The present invention is characterized in that a cobalt-based super heat-resistant alloy powder or a nickel-based super heat-resistant alloy powder is used as the auxiliary material powder.

In the present invention, a mixed powder obtained by adding a sintering aid powder to the above-mentioned mixed powder in which hard carbide powder is added to the diamond powder is sintered at a sintering temperature that satisfies the temperature and pressure conditions in the diamond stable region. This is a method for producing a diamond-hard carbide composite sintered body, which is characterized in that the sintering operation is performed by exposing the body to a high pressure.

As explained above, the present invention adds a hard carbide powder that reinforces the mechanical strength of the diamond sintered structure to a diamond powder having extremely high hardness, and further combines the diamond powder and the hard carbide powder. A mixed powder to which cobalt-based super heat-resistant alloy powder or nickel-based super heat-resistant alloy powder is added as a sintering aid powder to assist in the sintering of the mixed powder is used at a sintering temperature that satisfies the temperature and pressure conditions in the stable region of diamond. and sintering pressure,
An object of the present invention is to provide an industrially effective method for producing a diamond-hard carbide composite sintered body that maintains extremely high hardness, has strong mechanical strength and heat resistance, and has excellent performance as a material for cutting tools. This is the purpose.

Next, the operation of manufacturing a diamond-hard carbide composite sintered body by the method of the present invention will be explained.

The raw material for sintering includes diamond powder of 40% to 6% by weight.
0 weight ratio, titanium carbide, zirconium carbide, hafnium carbide, vanadium carbide, niobium carbide, tantalum carbide,
Powder of one type of carbide selected from among chromium carbide, molybdenum carbide, tungsten carbide, boron carbide, and silicon carbide, or a mixed powder of two or more types of carbide, with a weight ratio of 66 to 2
A mixed powder is used in which a cobalt-based super heat-resistant alloy powder, a cobalt-based super heat-resistant alloy powder, and a nickel-based super heat-resistant alloy powder are mixed in a ratio selected from within the ratio range of 24 weight ratio to 20 weight ratio. The work of sintering the raw material for sintering prepared in this way is performed by exposing it to a sintering temperature and pressure that satisfy the temperature and pressure conditions in the stable region of diamond, and performing preliminary sintering work and main sintering work. It is carried out in two stages: sintering and pre-sintering, in which the pre-sintering temperature is in the range of 900°C to 1,100°C and 40,000 to 9/c, A to 45.500°C.
The pressure for pre-sintering is within the range of 1,300°C to 1,600°C during the main sintering process.
Main sintering temperature within the range of 51,000 kg/ca
to 60,000 kg/car. To start the sintering operation, first, the prepared sintering raw material is filled into a container, and the container is loaded into a high temperature and high pressure generating chamber. Next, the pre-sintering pressure (40,000k7/
cxt~45.500 kg/tr! ) was added at the same time as the selected pre-sintering temperature (900℃~1,10℃).
0℃) and pressurize and heat it for 10 minutes to 50℃.
Hold for a minute to heat the pre-sintered state.

Next, the pressure for main sintering was increased by increasing the pressure for preliminary sintering (51,000 N/crA~60,00 crA).
The pressure was increased to 0.97 c,j), and then the heating at the pre-sintering temperature that had been maintained was increased to the selected main sintering temperature (1,300 °C to 1.6 (10 °C)). The pressurized and heated state is maintained for 20 to 60 minutes to produce a main sintered state.The state after this main sintering operation constitutes a liquid phase sintered body. Next, heating was stopped while maintaining the main sintering pressure that had been applied, and the high-temperature and high-pressure generation chamber was further cooled to bring the temperature inside the chamber to 500°C.
The temperature drops to . The liquid phase portion of the liquid phase sintered body subjected to this cooling operation solidifies to produce a solid phase sintered body. The solid state sintered body obtained by completing the sintering process according to the method of the present invention described above is composed of individual particles in an aggregate formed by mixing a large number of diamond particles and a large number of hard carbide particles. The gaps between the particles are filled with a sintered structure with a spongy structure made of cobalt-based super heat-resistant alloy powder or nickel-based super heat-resistant alloy powder, and the sintered structure with a spongy structure is formed into individual diamonds. A cubic boron nitride-hard carbide composite sintered body characterized by a sintered structure composed of particles and individual hard carbide particles, which maintains extremely high hardness and has strong mechanical strength and heat resistance. It is a diamond-hard carbide composite sintered body having excellent performance as a cutting tool material.

Next, the operation of manufacturing a diamond-hard carbide composite sintered body by the method of the present invention will be explained using examples.

Example 1 Raw materials for sintering include 50% by weight of diamond powder, 30% by weight of tungsten carbide powder, 68% by weight of cobalt manufactured by Paradare 4 Sokufu, 26% by weight of chromium, and 5% by weight of tungsten. A mixed powder was used in which Nutelite Otsu powder, which had a composition ratio of 1 part by weight of carbon, was mixed at a ratio of 20% by weight. The sintering raw materials prepared in this manner were filled into a container, and the container was loaded into a high temperature and high pressure generation chamber. Next, the sintering work is divided into two parts: preliminary sintering work and main sintering work.
The pre-sintering temperature used in the pre-sintering step is 1.100°C, the pre-sintering pressure is 45.500 kq/crl,
The main sintering temperature used in the main sintering work is 1.50.
A temperature of 0℃ was selected, and the pressure for main sintering was 57,000k.
A pressure of g/ca was chosen. Next, to start the sintering work, first, the pre-sintering pressure of 45.500 k selected for the sintering raw material in the container loaded into the high-temperature and high-pressure generating chamber was applied.
A pressure of 7/cr; The heating required to maintain the temperature at 1.100° C. was maintained for 60 minutes.

Next, the pre-sintering pressure that had been applied was increased to the selected main sintering pressure of 57.000 k7/crl, and the main sintering pressure was applied. At the same time, the pre-sintered body, which has been heated to maintain the pre-sintering temperature, is further heated to the selected main sintering temperature of 1.500°C. .500
The heating required to maintain the temperature in °C was maintained for 50 minutes.

Next, the main sintering pressure applied was 57,000 k7/
Only heating was stopped while Ca was maintained, and the high temperature and high pressure generation chamber was further water cooled from the outside. Next, after the temperature in the chamber was lowered to 300° C., the main sintering pressure that had been maintained was set to normal pressure. Next, the container was pushed out of the high-temperature, high-pressure generation chamber, and the solid-phase main sintered body was taken out from inside the container.

The obtained sintered body has a spongy structure in which Stellite 6 powder is sintered in the gaps between individual particles in an aggregate made of a mixture of many diamond particles and many tungsten carbide particles. It is filled with sintered structure, and the sintered structure of the spongy structure is made up of individual diamond particles and individual stainless steel composite sintered bodies, which maintains extremely high hardness and has strong mechanical strength and heat resistance. The diamond-hard carbide composite sintered body had excellent performance as a material for cutting tools.

Example 2゜The raw materials for sintering include 50% by weight of diamond powder, 30% by weight of molybdenum carbide powder, 61.92% by weight of nickel manufactured by Powdarex, and 16565% by weight of chromium.
Hastelloy C with a composition ratio of 17% by weight of livedenum, 4.5% by weight of tungsten, and 00808% by weight of carbon.
A mixed powder obtained by mixing powders of 20% by weight was used. The operations up to producing a solid-phase main sintered body using the sintering raw material prepared in this manner were carried out in the same manner as in Example 1. The resulting nine-piece sintered body is a spongy-like structure in which Hastelloy C powder is sintered into the gaps between the individual particles in an aggregate made up of a mixture of many diamond particles and many molybdenum carbide particles. A diamond-molybdenum carbide composite characterized by a sintered structure filled with a sintered structure in which the cavernous sintered structure is composed of individual diamond particles and individual molybdenum carbide particles. The diamond hard carbide composite sintered body was a sintered body that had extremely high hardness, strong mechanical strength, and heat resistance, and had excellent performance as a material for cutting tools.

Example 6 Raw materials for sintering include 50% by weight of diamond powder, 28% by weight of titanium carbide powder, and 22% by weight of Hastelloy C powder manufactured by Powderex (composition is described in Example 2).
A mixed powder mixed in the ratio was used. The operation for producing a solid-phase main sintered body using the sintering raw material prepared in this manner was carried out in the same manner as in Example 1.

The obtained sintered body has a spongy shape made by sintering Hastelloy C powder in the gaps between individual particles in an aggregate formed by mixing many diamond particles and many titanium carbide particles. A diamond-titanium carbide composite characterized by a sintered structure filled with a sintered structure in which the cavernous sintered structure is composed of individual diamond particles and individual titanium carbide particles. Diamond is a sintered body that maintains extremely high hardness, has strong mechanical strength and heat resistance, and has excellent performance as a cutting tool material - Example 4゜ Diamond powder is used as a raw material for sintering. , 50% by weight of powder, 22% by weight of tungsten carbide powder, 5% by weight of tantalum carbide powder, and 25% by weight of Stellite 6 powder manufactured by Bakudaresoku Co., Ltd. (the composition is described in Example 1). A mixed mixture was used. The work to produce a solid-phase main sintered body using the sintering raw material prepared in this way is as described in Example 1.
It was done in the same way as in the case of The obtained sintered body contains Stellite 6 powder in the gaps between individual particles in an aggregate formed by mixing a large number of diamond powders, a large number of tungsten carbide particles, and a large number of tantalum carbide particles. It is filled with a spongy sintered structure formed by sintering.
A diamond-tungsten carbide-tantalum carbide composite sintered body characterized by a sintered structure whose cavernous structure is composed of individual diamond particles, individual tungsten carbide particles, and individual tantalum carbide particles bonded together. The diamond-hard carbide composite sintered body has excellent performance as a material for cutting tools, maintaining extremely high hardness, strong mechanical strength, and heat resistance.

Example 5 The raw materials for sintering were 50% by weight of diamond powder, 22% by weight of tungsten carbide powder, 5% by weight of niobium carbide powder, and Hastelloy C manufactured by Powderex (the composition was described in Example 2). ) was used in a proportion of 23% by weight. The operations up to producing a solid-phase main sintered body using the sintering raw material prepared in this manner were carried out in the same manner as in Example 1. The obtained sintered body contains Hastelloy C powder in the gaps between individual particles in an aggregate formed by mixing a large number of diamond particles, a large number of tungsten carbide particles, and a large number of niobium carbide particles. is filled with a sintered tissue with a spongy structure formed by sintering, and the sintered tissue with a spongy structure is composed of individual diamond particles, individual tungsten carbide particles, and individual niobium carbide particles bonded together. It is a diamond-tank stainless steel-niobium carbide composite sintered body characterized by a sintered structure that maintains extremely high hardness, as well as strong mechanical strength and heat resistance, and has excellent performance as a cutting tool material. It was a diamond-hard carbide composite sintered body.

Example 6 Raw materials for sintering include 56% by weight of diamond powder, 20% by weight of silicon carbide powder, 7652652% by weight of nickel manufactured by Powderex, 19% by weight of 19% by weight of nickel, and 1% by weight of cobalt.
A mixed powder was used in which Naimoninoku 80A powder was mixed in a composition ratio of 22% by weight of titanium, 11% by weight of aluminum, and 0.18% by weight of carbon at a ratio of 24% by weight. The operations up to producing a solid-phase main sintered body using the sintering raw material prepared in this manner were carried out in the same manner as in Example 1.

The obtained sintered body is a sponge formed by sintering Naimoninoku 80A powder into the gaps between individual particles in an aggregate formed by mixing a large number of diamond particles and a large number of silicon carbide particles. A diamond-silicon carbide characterized by a sintered structure filled with a sintered structure having a sintered structure, and the sintered structure having a spongy structure formed by bonding individual diamond particles and individual silicon carbide particles. The diamond-hard carbide composite sintered body was a composite sintered body that maintains extremely high hardness, has strong mechanical strength and heat resistance, and has excellent performance as a cutting tool material.

Example 7 The raw materials for sintering included 56 parts by weight of diamond powder, 20 parts by weight of boron carbide powder, and 24 parts by weight of Naimoninoku 80A (composition was described in Example 6) powder manufactured by Powdarex.
A mixed powder was used which was mixed in proportions by weight. The operation for producing a solid-phase main sintered body using the sintering raw material prepared in this manner was carried out in the same manner as in Example 1. The obtained sintered body has a spongy shape formed by sintering Naimonisoku 80A powder into the gaps between individual particles in an aggregate formed by mixing a large number of diamond particles and a large number of boron carbide particles. Diamond-Boron Carbide Composite Synthesis is characterized by a sintered structure filled with sintered tissue with a spongy structure that is composed of individual diamond particles and individual boron carbide particles. The diamond-hard carbide composite sintered body had extremely high strength, strong mechanical strength, and heat resistance, and had excellent performance as a cutting tool material.

A chip made of a diamond-hard carbide composite sintered body manufactured in the example according to the method of the present invention described above, and a diamond powder of 77% by weight and a cobalt powder of 23% by weight.
Using a chip made of a diamond sintered body produced by sintering a mixture with a weight ratio of 88
Using a piston material made of Shirumin, an aluminum alloy with a composition of 12 parts by weight and 12 parts by weight, the piston material was made with a diameter of 55 mm.
Mi9. Cutting work was performed to form a cylindrical surface with a length of 40 mm. When using a chip made of the above-mentioned diamond sintered body in that work, it is necessary to polish it continuously for - times.
4.100 pieces could be cut, whereas when using a diamond-hard carbide composite sintered tip manufactured by the method of the present invention, 14.
I was able to cut 200 to 16,600 pieces. As is clear from this cutting experiment, when cutting aluminum alloys, the diamond-hard carbide composite sintered chips manufactured by the method of the present invention are more effective than chips made of diamond sintered bodies using only cobalt as a binder. It was possible to achieve extremely high productivity with the chip made of the diamond-hard carbide composite sintered body, proving that the method of manufacturing a diamond-hard carbide composite sintered body of the present invention is an industrially effective method.

Claims (1)

[Claims] 40% to 60% by weight of diamond powder, 36% to 20% by weight of hard carbide powder, and 24% of cobalt-based super heat-resistant alloy powder or nickel-based super heat-resistant alloy powder.
A mixed powder mixed at a selected ratio within the range of 20% by weight is used as a raw material for sintering, and the work of sintering the raw material for sintering is performed under exposure pressure conditions in the stable region of diamond. The preliminary sintering work is carried out in two stages, the preliminary sintering work and the main sintering work, using a sintering temperature and a sintering pressure that satisfy the following conditions. Using a pre-sintering temperature within the range and a pre-sintering pressure within the range of 40,000 kg/ca to 45,500 kg/crtr, the main sintering operation was carried out at 1,300°C to 1,300°C.
．． Main sintering temperature within the range of 600℃ and 51,000k
g/ca to 60. Manufacturing method of OOO composite sintered body.