CN107311663A - A kind of new tantalum nitride hard alloy and preparation method thereof - Google Patents

Abstract

The invention discloses a novel tantalum nitride hard alloy and a preparation method thereof, and mainly relates to the field of hard alloys. The invention adopts a pure-phase sintering method without adding a binder to prepare a tantalum nitride hard alloy sintered block with good crystal morphology and microstructure for the first time. Through X-ray diffraction and scanning electron microscope analysis, it is found that the cemented carbide provided this time has the characteristics of small grain size, high density and stable structure. Due to the simple preparation process and higher hardness than commercial tungsten carbide, it is developing into a new type of hard alloy with high hardness, high strength and high toughness.

Description

A kind of novel tantalum nitride cemented carbide and its preparation method

technical field

The invention relates to a novel tantalum nitride hard alloy, in particular to a novel tantalum nitride hard alloy and a preparation method thereof.

Background technique

Superhard materials have a wide range of industrial applications, such as cutting tools. Diamond is the material with the highest hardness known. In order to obtain hard materials similar to diamond, people have made great progress in the preparation and theoretical research of boron carbon nitrogen series compounds. Another way to explore superhard materials is to introduce covalently bonded light elements (such as boron, carbon, nitrogen, oxygen) into transition metals to improve the hardness of materials, which is still in its infancy. Pure transition metals have high bulk modulus due to their high valence electron density, but their hardness is very small. For example, although the bulk modulus of metal osmium (Os) reaches about 410 GPa, its hardness But only one-thirtieth of a diamond. The introduction of covalent bonding type elements into the transition metal lattice will produce strong directional covalent bonds, thereby greatly improving its ability to resist plastic and elastic deformation, and obtaining high hardness materials, such as the formation of metal tungsten and carbon After tungsten carbide, its hardness is three times that of pure metal tungsten.

Bulk sintering of 5d transition metal nitrides and borides has always been a great challenge in the exploration of high hardness materials. As a 5d transition metal nitride, tantalum nitride has high bulk elastic modulus and hardness, and the sintering problem of its bulk has been plagued by people. In order to obtain its bulk sintered body, we used the high temperature and high pressure conditions of the domestic six-sided top press, and at the same time adopted the pure-phase sintering method without adding a binder, to prepare a high-hardness bulk tantalum nitride cemented carbide for the first time. It has been confirmed again from experiments that the introduction of covalently bonded elements into the transition metal lattice will produce strong directional covalent bonds, thereby improving the feasibility of its resistance to plastic and elastic deformation. The preparation process of the invention is relatively simple, easy for industrial production, and has higher hardness than commercial tungsten carbide, and will become a new type of hard alloy with high hardness, high strength and high toughness and be used in industrial production and other fields.

Contents of the invention

The purpose of the present invention is to provide a novel tantalum nitride cemented carbide sintered block and its preparation method. The alloy block has only one component - tantalum nitride. This invention uses a domestic six-sided top large cavity press as the sintering equipment. During the sintering process, no binder is added for pure-phase sintering, and its large sintered body is obtained for the first time. . The cemented carbide provided by the invention has remarkable characteristics: small grain size, low porosity, stable structure and high density. The Vickers hardness of the cemented carbide sintered block provided by the present invention can reach 30GPa (the Vickers hardness of 15s under the loading force of 3 kg), which is comparable to that of the tungsten carbide cemented carbide sold on the market (the Vickers hardness of 15s under the loading force of 3 kg). Compared with Vickers hardness (Vickers hardness is 17GPa), it has a huge advantage, which effectively solves the problem of low hardness and toughness of commercially available tungsten carbide.

Novel tantalum nitride cemented carbide provided by the invention and preparation method comprise the following steps:

1 Grinding tantalum nitride powder with hexagonal structure or cubic structure;

2 Vacuum-treat the ground tantalum nitride powder and pre-press it into a cylindrical block;

3 Put the pre-pressed cylinder into the high-pressure synthesis block; place the assembled high-pressure synthesis block in the synthesis cavity of the large-cavity press for high-temperature and high-pressure sintering, the sintering pressure is not lower than 1GPa; the synthesis time is not less than 1min;

4 After the sintering is completed, lower the temperature and release the pressure, remove the inclusions and take out the sintered tantalum nitride cemented carbide;

In the above-mentioned technical scheme, the high temperature and high pressure conditions are preferred to control the temperature at 600-2200°C, the pressure at 1-8GPa, the time at 1-120min, and the holding time at 5-120min;

In the above scheme, the initial powder of tantalum nitride, preferably hexagonal structure or cubic structure tantalum nitride is used as the initial powder. Under high temperature and high pressure conditions, the initial powder of tantalum nitride transforms from a hexagonal structure to a tungsten carbide structure, and at the same time, it is sintered to form a block. Another cubic tantalum nitride powder is directly sintered together to form a tantalum nitride cemented carbide sintered body.

In the above scheme, the vacuum treatment temperature of tantalum nitride is 1200°C, and the temperature is kept for 2 hours to completely remove oxides and gases on the surface of tantalum nitride.

In the above technical solution, the tantalum nitride powder can be pre-pressed into a block, or pressed into two overlapping blocks, and put into a high-pressure synthesis block.

In the above technical solution, the equipment for generating high temperature and high pressure conditions may be a six-sided press, a double-sided press, a four-sided press, and other high-temperature and high-pressure equipment.

In the above technical solution, the high-pressure synthetic block is constituted as follows: the prefabricated block or the alternately stacked blocks are put into the graphite tube in the pyrophyllite assembly block, and the upper and lower sheets of the graphite tube are respectively graphite sheets , molybdenum sheets and conductive steel rings, and the composite press is preferably a press with a six-sided top and a large cavity.

Grinding the initial material of tantalum nitride is mainly to refine the grains of the initial material so as to obtain tantalum nitride cemented carbide with higher hardness.

In the above technical solution, a binder can be added during the sintering process of the tantalum nitride cemented carbide to reduce the temperature and pressure during the high-pressure synthesis process, so as to be more suitable for industrial production and improve productivity.

The invention is based on the phase transition from the hexagonal structure of tantalum nitride to the structure of tungsten carbide or the cemented carbide prepared by direct sintering from the cubic phase. High-purity tantalum nitride powder is used as the initial material, and no binder is added for pure-phase sintering. The cemented carbide obtained in the present invention has very obvious characteristics, such as high hardness and high toughness. The tantalum nitride hard alloy prepared by the invention is tested and analyzed by a scanning electron microscope, and the grain size of the sintered block is about 1 micron, with few pores, high density and small grain size. The present invention can be synthesized and sintered under lower temperature and pressure conditions (the lowest sintering conditions are pressure 1GPa, temperature 600°C), and the preparation conditions are lower than those for industrial production of synthetic diamond and cubic boron nitride (temperature 1400°C, 5.5GPa ) with low preparation conditions. Traditional diamond production equipment can prepare tantalum nitride cemented carbide. The operation is simple, and the hardness of the sintered body can reach 30GPa. It can be sintered into large blocks of cemented carbide with high hardness and high toughness. It is easy to promote and scale production Etc.

Description of drawings:

Figure 1 shows the XRD pattern of tantalum nitride cemented carbide synthesized under high temperature and high pressure conditions.

Fig. 2 shows the scanning electron micrograph of the tantalum nitride cemented carbide (Example 5) prepared by the present invention.

Fig. 3 shows the results of the hardness test of the tantalum nitride cemented carbide (Example 5) prepared by the present invention.

Fig. 4 represents the physical figure of the tantalum nitride cemented carbide (embodiment five) prepared by the present invention

detailed description:

Example 1: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press. At a temperature of about 600°C and a pressure of about 1.2GPa, after 1-5 minutes of heat preservation and pressure preservation, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride hard quality alloy.

Embodiment 2: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for high-temperature vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite in the pyrophyllite synthetic block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1200°C and a pressure of about 2GPa, after 30 minutes of heat preservation and pressure, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 3: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for high-temperature vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite in the pyrophyllite synthetic block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1200°C and a pressure of about 3GPa, after about 60 minutes of heat preservation and pressure holding, take out the synthesis material after cooling down and reducing the pressure, the material is tantalum nitride cemented carbide .

Embodiment 4: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for high-temperature vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite in the pyrophyllite synthetic block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of 1400°C and a pressure of about 5GPa, after 20 minutes of heat preservation and pressure preservation, the synthetic material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Embodiment 5: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for high-temperature vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite in the pyrophyllite synthetic block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press, at a temperature of about 1400°C and a pressure of 5.5GPa, after 30 minutes of heat preservation and pressure holding, the synthetic material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Embodiment 6: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of 1400°C and a pressure of about 2GPa, after 30 minutes of heat preservation and pressure preservation, the synthetic material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Embodiment 7: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic chamber of the large press. At a temperature of 1400°C and a pressure of about 3GPa, after 60 minutes of heat preservation and pressure preservation, the synthetic material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Embodiment 8: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of 1400°C and a pressure of about 5GPa, after 10 minutes of heat preservation and pressure holding, the synthetic material is taken out after cooling down and reducing pressure. The material is tantalum nitride cemented carbide.

Example 9: Grind tantalum nitride powder with a hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1400°C and a pressure of about 5GPa, after 15 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 10: Grind tantalum nitride powder with a hexagonal or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press. At a temperature of about 1400°C and a pressure of about 5GPa, after 30 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 10: Grind tantalum nitride powder with a hexagonal or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press, at a temperature of about 1400°C and a pressure of about 5GPa, after 40 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Embodiment 11: Take tantalum nitride powder with hexagonal structure or cubic structure for grinding, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press. At a temperature of about 1400°C and a pressure of about 5GPa, after 50 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 12: Grind tantalum nitride powder with a hexagonal or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press, at a temperature of about 1400°C and a pressure of about 5GPa, after 60 minutes of heat preservation and pressure, the synthetic material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 13: Grind tantalum nitride powder with a hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press, at a temperature of about 1400°C and a pressure of about 5GPa, after 80 minutes of heat preservation and pressure holding, the synthetic material is taken out after the temperature and pressure drop, and the material is tantalum nitride cemented carbide.

Embodiment 14: Grind tantalum nitride powder with hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthetic block into the synthetic chamber of the large press. At a temperature of about 1600°C and a pressure of about 5GPa, after 10 minutes of heat preservation and pressure holding, the synthetic material is taken out after cooling down and reducing pressure. The material is tantalum nitride cemented carbide.

Example 15: Grind tantalum nitride powder with a hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press, at a temperature of about 1600°C and a pressure of about 5GPa, after 20 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling down and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 16: Grind tantalum nitride powder with a hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press. At a temperature of about 1600°C and a pressure of about 5GPa, after 40 minutes of heat preservation and pressure preservation, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 17: Grind tantalum nitride powder with a hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1600°C and a pressure of about 5GPa, after 50 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Embodiment 18: Grind tantalum nitride powder with a hexagonal structure or a cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of about 1600°C and a pressure of about 5GPa, after 60 minutes of heat preservation and pressure holding, the synthetic material is taken out after cooling down and reducing pressure. The material is tantalum nitride cemented carbide.

Embodiment 19: Grind tantalum nitride powder with a hexagonal or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1600°C and a pressure of about 5GPa, after 80 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 20: Grind tantalum nitride powder with a hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1600°C and a pressure of about 5.5GPa, after 10 minutes of heat preservation and pressure holding, take out the synthesis material after cooling down and reducing the pressure, the material is tantalum nitride cemented carbide . Example 21: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press, at a temperature of about 1600°C and a pressure of about 5.5GPa, after 20 minutes of heat preservation and pressure, the synthetic material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide .

Example 22: Grinding tantalum nitride powder with a hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1600°C and a pressure of about 5.5GPa, after 30 minutes of heat preservation and pressure holding, take out the synthesis material after cooling down and reducing the pressure, the material is tantalum nitride cemented carbide .

Example 23: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1600°C and a pressure of about 5.5GPa, after 40 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide .

Example 24: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1600°C and a pressure of about 5.5GPa, after 50 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide .

Example 25: Grinding tantalum nitride powder with a hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the vacuum-treated tantalum nitride powder, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1600°C and a pressure of about 5.5GPa, after 60 minutes of heat preservation and pressure, the synthesis material is taken out after cooling down and reducing pressure, and the material is tantalum nitride cemented carbide .

Example 26: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic chamber of the large press. At a temperature of about 1200°C and a pressure of about 3GPa, after 10 minutes of heat preservation and pressure holding, the synthetic material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 27: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press. At a temperature of about 1200°C and a pressure of about 3GPa, after 20 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 28: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1200°C and a pressure of about 3GPa, after 30 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 29: Grinding tantalum nitride powder with a hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the vacuum-treated tantalum nitride powder, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of about 1200°C and a pressure of about 3GPa, after 40 minutes of heat preservation and pressure preservation, the synthetic material is taken out after cooling down and reducing pressure. The material is tantalum nitride cemented carbide.

Example 30: Grind tantalum nitride powder with a hexagonal or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press. At a temperature of about 1200°C and a pressure of about 3GPa, after 50 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 31: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic chamber of the large press. At a temperature of about 1400°C and a pressure of about 3GPa, after 10 minutes of heat preservation and pressure holding, the synthetic material is taken out after cooling down and reducing pressure. The material is tantalum nitride cemented carbide.

Example 32: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press. At a temperature of about 1400°C and a pressure of about 3GPa, after 20 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 33: Grinding tantalum nitride powder with a hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press, at a temperature of about 1400°C and a pressure of about 3GPa, after 30 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 34: Grinding tantalum nitride powder with a hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1400°C and a pressure of about 3GPa, after 40 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 35: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of about 1400°C and a pressure of about 3GPa, after 50 minutes of heat preservation and pressure holding, the synthetic material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 36: Grinding tantalum nitride powder with hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press. At a temperature of about 1600°C and a pressure of about 3GPa, after 10 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 37: Grinding tantalum nitride powder with hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press. At a temperature of about 1600°C and a pressure of about 3GPa, after 20 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 38: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press. At a temperature of about 1600°C and a pressure of about 3GPa, after 30 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 39: Grinding tantalum nitride powder with hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1600°C and a pressure of about 3GPa, after 40 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 40: Grind tantalum nitride powder with a hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of about 1600°C and a pressure of about 3GPa, after 50 minutes of heat preservation and pressure preservation, the synthetic material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 41: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of about 1600°C and a pressure of about 2GPa, after 10 minutes of heat preservation and pressure holding, the synthetic material is taken out after cooling down and reducing pressure. The material is tantalum nitride cemented carbide.

Example 42: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic chamber of the large press. At a temperature of about 1800°C and a pressure of about 2GPa, after 10 minutes of heat preservation and pressure preservation, the synthetic material is taken out after cooling down and reducing pressure. The material is tantalum nitride cemented carbide.

Example 43: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press. At a temperature of about 1800°C and a pressure of about 5GPa, after 10 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 44: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press. At a temperature of about 1800°C and a pressure of about 5GPa, after 40 minutes of heat preservation and pressure preservation, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 45: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press. At a temperature of about 1800°C and a pressure of about 5GPa, after 10 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction. The material is tantalum nitride cemented carbide.

Example 46: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1800°C and a pressure of about 8GPa, after 5 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 47: Grinding tantalum nitride powder with hexagonal structure or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthetic block into the synthetic cavity of the large press. At a temperature of about 1800°C and a pressure of about 4GPa, after 10 minutes of heat preservation and pressure preservation, the synthetic material is taken out after cooling down and reducing pressure. The material is tantalum nitride cemented carbide.

Example 48: Grind tantalum nitride powder with a hexagonal or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the vacuum-treated tantalum nitride powder, and use a mold The tantalum nitride is pre-pressed into a cylindrical block, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis cavity of the large press, at a temperature of about 1800°C and a pressure of about 2.5GPa, after 30 minutes of heat preservation and pressure holding, take out the synthesis material after cooling down and lowering the pressure, the material is tantalum nitride cemented carbide .

Example 49: Grinding tantalum nitride powder with hexagonal or cubic structure, putting the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, taking out the tantalum nitride powder after vacuum treatment, The tantalum nitride is pre-pressed into a cylindrical block with a mold, and the pressed cylindrical block is put into the graphite tube in the pyrophyllite synthesis block. The upper and lower ends of the graphite tube are assembled with graphite sheets, molybdenum sheets and conductive steel rings in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press, at a temperature of about 1000°C and a pressure of about 5GPa, after 50 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

Example 50: Grind tantalum nitride powder with a hexagonal structure or cubic structure, put the ground powder into a vacuum furnace for vacuum treatment at 1000°C-1600°C, take out the tantalum nitride powder after vacuum treatment, and use The mold pre-presses the tantalum nitride into a cylindrical block, puts the pressed cylindrical block into the graphite tube in the pyrophyllite synthesis block, and assembles graphite sheets, molybdenum sheets and conductive steel rings at the upper and lower ends of the graphite tube in sequence. After assembling, put the synthesis block into the synthesis chamber of the large press, at a temperature of about 800°C and a pressure of about 5GPa, after 30 minutes of heat preservation and pressure holding, the synthesis material is taken out after cooling and pressure reduction, and the material is tantalum nitride cemented carbide.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications made within the spirit and principles of the present invention, equivalent replacements and improvements, etc., should be included in the protection of the present invention. within range.

Claims (6)

1. a kind of new tantalum nitride hard alloy, it is characterised in that：Its composition is the tantalum nitride of six sides or cubic structure.

2. a kind of new tantalum nitride hard alloy according to claim 1, it is characterised in that：It is described to prepare tantalum nitride hard Alloy sintering block original material composition is the tantalum nitride of hexagonal structure or cubic structure.

3. a kind of new tantalum nitride hard alloy according to claim 1, it is characterised in that：The initial material of described tantalum nitride Expect for powder, particle or block etc..

4. the preparation method of the new tantalum nitride hard alloy according to claim 1-3, its character is：Described Tantalum nitride hard alloy prepares the pure phase sintering process using binder free, including following steps：

（1）Hexagonal structure or cubic structure tantalum nitride powder are ground；

（2）High-temperature vacuum processing is carried out to the tantalum nitride powder after grinding, and is pressed into cylinder in advance；

（3）The cylinder being pressed into is put into high-pressure synthesis block；

（4）The high-pressure synthesis block assembled is placed in press synthesis chamber and carries out HTHP sintering, sintering pressure is not less than 1GPa, generated time is no less than 1min；

（5）Cooling release removes inclusion enclave after sintering is completed, you can obtain tantalum nitride sintering cemented carbide described in claim 1 Block.

5. new tantalum nitride hard alloy preparation method according to claim 4, it is characterised in that：Described tantalum nitride is hard Matter alloy preparation condition is：600-2200 DEG C of temperature, pressure 1-20GPa, soaking time 1-120 minutes.

6. new tantalum nitride hard alloy preparation method according to claim 4, it is characterised in that：Described press is six Face high pressure apparatus, belt type press, four sides high pressure apparatus and the equipment with high-temperature and high-pressure conditions.