CN113135756A

CN113135756A - Preparation method of carbon silicon carbide ceramic target blank

Info

Publication number: CN113135756A
Application number: CN202110454130.2A
Authority: CN
Inventors: 姚力军; 王巨宝; 王学泽; 杨慧珍
Original assignee: Shanghai Rongchuangkaixun Special Material Co ltd
Current assignee: Shanghai Rongchuangkaixun Special Material Co ltd
Priority date: 2021-04-26
Filing date: 2021-04-26
Publication date: 2021-07-20
Anticipated expiration: 2041-04-26
Also published as: CN113135756B

Abstract

The invention relates to a preparation method of a carbon silicon carbide ceramic target blank, which comprises the following steps: filling carbon-silicon carbide composite powder into a mold, performing cold pressing, and then sequentially performing hot-pressing sintering and cooling to obtain the carbon-silicon carbide ceramic target blank; the sphericity of the particles in the carbon-silicon carbide composite powder is 0.8-1, and the particle size is 120-180 mu m; and the hot-pressing sintering comprises a first heat preservation, a second heat preservation and a heat preservation and pressure maintaining which are sequentially carried out. The preparation of the high-performance target blank is realized by controlling the sphericity and the proportion of the raw materials in the preparation process and adopting a pre-cold pressing mode, the prepared target blank and the back plate can be well infiltrated when being welded, so that the target and the back plate can be well welded, the welding bonding rate is up to 99% or more, the density is up to more than 99%, and the yield is up to more than 98%.

Description

Preparation method of carbon silicon carbide ceramic target blank

Technical Field

The invention relates to the field of targets, in particular to a preparation method of a silicon carbide ceramic target blank.

Background

Along with the expansion of the thermal printing and 3D printing markets in recent years, the demand of silicon carbide target materials in the industry is increasingly increased. However, because the silicon carbide target material has special material properties, great production technical difficulty and difficult post-processing, the silicon carbide target material with high density and stable performance cannot be produced at present in China, and the requirement of the heat-sensitive industry on the quality of the target material cannot be met.

For example, CN110273125A discloses a method for preparing a fluorescent silicon carbide thin film. A method for preparing a fluorescent silicon carbide film by magnetron sputtering is characterized by comprising the following steps: (1) selecting a preparation material: selecting monocrystalline silicon as a substrate material, selecting silicon carbide as a sputtering target material, and selecting porous anodic aluminum oxide as a template; (2) preparing a growth template: transferring the porous anodic alumina template to a monocrystalline silicon substrate material to obtain a growth template; (3) the growth template is sent into a vacuum cavity of a magnetron sputtering device, and the sputtering target material is selected from silicon carbide; (4) heating and depositing: the temperature of the monocrystalline silicon substrate material is kept between 25 ℃ and 600 ℃, the heating rate is 20 ℃ per minute, and the temperature keeping time of the monocrystalline silicon substrate material is 1 minute to 120 minutes; growing a silicon carbide film on the porous anodic aluminum oxide template; and obtaining the fluorescent silicon carbide film. The method has the characteristics of simple preparation process, high film coating speed, compact film layer, good adhesiveness, good repeatability and the like, and realizes the full-fluorescence luminescence of blue light, yellow light and red light.

For another example, CN111320478A discloses a method for preparing a carbon-silicon ceramic target. The preparation method comprises the following steps: (1) weighing graphite powder, simple substance silicon powder and SiC powder according to the carbon-silicon ratio of the target material to be prepared, wherein the simple substance silicon powder accounts for 5 at% -15 at% of the total amount of the graphite powder, the simple substance silicon powder and the SiC powder; (2) crushing and mixing graphite powder and elemental silicon powder by adopting a horizontal shaft ball milling method to obtain carbon-silicon pre-ball milled powder; (3) adding weighed SiC powder into the carbon-silicon pre-ball milled powder, placing the powder in a horizontal shaft ball milling tank, and carrying out ball milling and mixing for 2 hours to obtain composite raw material powder; (4) screening the composite raw material powder, putting the composite raw material powder into a graphite mold, putting the mold into a hot pressing furnace, filling argon when the vacuum is pumped to be less than 500pa, and adopting front-stage rapid heating, middle-stage liquid phase sintering and high-temperature argon protection sintering; (5) and cooling to obtain a carbon-silicon ceramic target blank, and processing, cleaning and drying to obtain the carbon-silicon ceramic target. The prepared carbon-silicon ceramic target has the relative density of more than 90 percent and the resistivity of less than 0.05 omega cm, and is suitable for preparing DLC films by sputtering.

However, when the target blank prepared in the prior art is used as a target material and a back plate for welding, the problem of low welding bonding rate caused by poor infiltration effect during welding still exists, and the problems of poor density, low yield and the like also exist.

Disclosure of Invention

In view of the problems in the prior art, one of the objectives of the present invention is to provide a method for preparing a carbon silicon carbide ceramic target blank, wherein the sphericity and the ratio of raw materials in the preparation process are controlled, and a pre-cold pressing manner is adopted to realize the preparation of a high-performance target blank, so that the prepared target blank and a back plate can be well infiltrated during welding, thereby ensuring that the target material and the back plate can be well welded, the welding bonding rate is as high as 99% or more, the density is significantly improved, and can reach more than 99%, and the yield is significantly improved to more than 98.

In order to achieve the purpose, the invention adopts the following technical scheme:

the invention provides a preparation method of a carbon silicon carbide ceramic target blank, which comprises the following steps:

filling carbon-silicon carbide composite powder into a mold, carrying out cold pressing, and then sequentially carrying out hot-pressing sintering and cooling to obtain the carbon-silicon carbide ceramic target blank;

the sphericity of the particles in the carbon-silicon carbide composite powder is 0.8-1, and the particle size is 120-180 mu m;

and the hot-pressing sintering comprises a first heat preservation, a second heat preservation and a heat preservation and pressure maintaining which are sequentially carried out.

According to the method for preparing the target blank, the preparation of the high-performance target blank is realized by controlling the sphericity and the proportion of the raw materials in the preparation process and adopting the pre-cold pressing, namely the specific hot-pressing sintering process, the prepared target blank and the back plate can be well infiltrated when being welded, so that the target and the back plate can be well welded, the welding bonding rate is up to 99% or more, the density is remarkably improved and can reach more than 99%, and the yield is remarkably improved and can reach more than 98%. The invention adopts the specific cold pressing technology to pretreat the composite powder with specific spheroidization degree, so that the powder is arranged in advance and integrated to prepare for the next sintering, and then the sintering adopts the specific multi-stage heating and heat preservation sintering process to realize the preparation of the high-performance target blank, thereby solving the problem of desoldering caused by insufficient infiltration when the target blank and the back plate are welded in the prior art.

In the present invention, the sphericity of the particles in the carbon-silicon carbide composite powder is 0.8 to 1, and may be, for example, 0.8, 0.82, 0.84, 0.86, 0.88, 0.9, 0.92, 0.94, 0.96, 0.98 or 1, but is not limited to the values listed, and other values not listed in this range are also applicable.

In the present invention, the particle size of the particles in the carbon-silicon carbide composite powder is 120-180. mu.m, and may be, for example, 120. mu.m, 125. mu.m, 130. mu.m, 135. mu.m, 140. mu.m, 145. mu.m, 150. mu.m, 155. mu.m, 160. mu.m, 165. mu.m, 170. mu.m, 175. mu.m, or 180. mu.m, but not limited to the above-mentioned values, and other values not specifically mentioned in the above range are also applicable.

In a preferred embodiment of the present invention, the carbon-silicon carbide composite powder has a mass ratio of carbon to silicon carbide of (1-2) to (1-3), and may be, for example, 1:1, 1:2, 1:3, 2:1, 2:3, or 47:53, but is not limited to the above-mentioned values, and other values not shown in the above-mentioned range are also applicable.

As a preferable technical scheme of the invention, the cold pressing is to mold the composite powder after mold filling.

Preferably, the cold pressing comprises a first cold pressing and a second cold pressing performed in sequence.

Preferably, the pressure of the first cold pressing is < 3MPa, and may be, for example, 2.5MPa, 2.4MPa, 2.3MPa, 2.2MPa, 2.1MPa, 2MPa, 1.9MPa, 1.8MPa, 1.7MPa, 1.6MPa or 1.5MPa, but is not limited to the recited values, and other values not recited in this range are also applicable.

Preferably, the first cold pressing time is 2-4s, for example 2s, 3s or 4s, etc., but is not limited to the recited values, and other values not recited in this range are equally applicable.

Preferably, the pressure of the second cold pressing is 10-15MPa, such as 10MPa, 11MPa, 12MPa, 13MPa, 14MPa or 15MPa, but not limited to the recited values, and other values not recited in this range are equally applicable.

Preferably, the second cold pressing has a dwell time of 2-5min, such as 2min, 3min, 4min or 5min, but not limited to the recited values, and other values not recited in this range are equally applicable.

As a preferable embodiment of the present invention, before the hot press sintering is started, a vacuum pumping treatment is performed.

Preferably, the vacuum degree is less than or equal to 100Pa, and may be, for example, 100Pa, 90Pa, 80Pa, 60Pa, 50Pa, 40Pa, or 30Pa, etc., but is not limited to the recited values, and other values not recited in the range are also applicable.

As a preferred technical scheme of the invention, the first heat preservation is to heat up to 1000-1100 ℃ at 10-12 ℃/min, then to heat up to 1800-1900 ℃ at 5-7 ℃/min, and then to preserve heat for 50-60 min.

In the present invention, the first heat-preservation temperature-rise to 1000-1100 ℃ has a temperature-rise rate of 10-12 ℃/min, for example, 10 ℃/min, 11 ℃/min or 12 ℃/min, but is not limited to the values listed, and other values not listed in the range are also applicable.

In the present invention, the first heat-retention temperature is raised to 1000-1100 ℃, for example, 1000 ℃, 1010 ℃, 1020 ℃, 1030 ℃, 1040 ℃, 1050 ℃, 1060 ℃, 1070 ℃, 1080 ℃, 1090 ℃ or 1100 ℃ and the like, but is not limited to the recited values, and other values not recited in the range are also applicable.

In the present invention, the rate of raising the temperature of the first heat preservation to 1800-1900 ℃ is 5-7 ℃/min, for example, 5 ℃/min, 6 ℃/min or 7 ℃/min, etc., but is not limited to the values listed, and other values not listed in the range are also applicable.

In the present invention, the first temperature rise to 1800-1900 ℃ may be, for example, 1800 ℃/min, 1810 ℃/min, 1820 ℃/min, 1830 ℃/min, 1840 ℃/min, 1850 ℃/min, 1860 ℃/min, 1870 ℃/min, 1880 ℃/min, 1890 ℃/min, 1900 ℃/min, or the like, but is not limited to the values listed, and other values not listed within this range may be similarly applied.

In the present invention, the first heat-retaining time is 50 to 60min, and may be, for example, 50min, 51min, 52min, 53min, 54min, 55min, 56min, 57min, 58min, 59min or 60min, but is not limited to the above-mentioned values, and other values not listed in the above range are also applicable.

As the preferable technical scheme of the invention, the second heat preservation is to heat the mixture to 2050-2150 ℃ for 20-30min at the speed of 3-5 ℃/min.

In the present invention, the temperature increase rate of the second heat-retention is 3 to 5 ℃/min, and may be, for example, 3 ℃/min, 4 ℃/min or 5 ℃/min, but is not limited to the values listed above, and other values not listed within this range are also applicable.

In the present invention, the temperature of the second heat-retention is 2050-2150 ℃, and for example, 2050 ℃, 2060 ℃, 2070 ℃, 2080 ℃, 2090 ℃, 2100 ℃, 2110 ℃, 2120 ℃, 2130 ℃, 2140 ℃ or 2150 ℃ may be used, but the present invention is not limited to the above-mentioned values, and other values not listed in the range are also applicable.

In the present invention, the time of the second heat preservation is 20 to 30min, and may be, for example, 20min, 21min, 22min, 23min, 24min, 25min, 26min, 27min, 28min, 29min or 30min, but is not limited to the values listed above, and other values not listed above in this range are also applicable.

In a preferred embodiment of the present invention, the holding temperature in the holding pressure is the holding temperature of the second heat preservation.

In a preferred embodiment of the present invention, the pressurizing rate in the heat and pressure maintaining is 0.4 to 0.45MPa/min, and may be, for example, 0.4MPa/min, 0.41MPa/min, 0.42MPa/min, 0.43MPa/min, 0.44MPa/min or 0.45MPa/min, but is not limited to the above-mentioned values, and other values not mentioned in the above-mentioned range are also applicable.

Preferably, the pressure in the heat-holding and pressure-maintaining is 35 to 40MPa, for example, 35MPa, 36MPa, 37MPa, 38MPa, 39MPa or 40MPa, etc., but is not limited to the values listed, and other values not listed in the range are also applicable.

Preferably, the time for holding the temperature and pressure is 180-.

As a preferable technical scheme of the invention, the temperature reduction is to inject protective gas after the hot-pressing sintering is finished and carry out furnace cooling.

Preferably, the furnace cooling end point temperature is < 200 ℃, for example 195 ℃, 190 ℃, 185 ℃, 180 ℃, 175 ℃, 170 ℃ or 160 ℃, but not limited to the recited values, and other values not recited in this range are equally applicable.

As a preferred technical scheme of the invention, the preparation method comprises the following steps: filling carbon-silicon carbide composite powder into a mold, carrying out cold pressing, and then sequentially carrying out hot-pressing sintering and cooling to obtain the carbon-silicon carbide ceramic target blank;

the sphericity of the particles in the carbon-silicon carbide composite powder is 0.8-1, and the particle size is 120-180 mu m; the mass ratio of carbon to silicon carbide in the carbon-silicon carbide composite powder is (1-2) to (1-3);

the cold pressing is to mold the composite powder after mold filling; the cold pressing comprises a first cold pressing and a second cold pressing which are sequentially carried out;

the pressure of the first cold pressing is less than 3 MPa; the time of the first cold pressing is 2-4 s; the pressure of the second cold pressing is 10-15 MPa; the pressure maintaining time of the second cold pressing is 2-5 min;

vacuumizing treatment is carried out before the hot-pressing sintering is started; the end point of the vacuum pumping is that the vacuum degree is less than or equal to 100 Pa;

the hot-pressing sintering comprises a first heat preservation, a second heat preservation and pressure preservation which are sequentially carried out;

the first heat preservation is to heat up to 1100 ℃ at the temperature of 1000-;

the second heat preservation is to heat up to 2050-;

the heat preservation temperature in the heat preservation and pressure maintaining process is the heat preservation temperature of the second heat preservation; the pressurizing rate in the heat preservation and pressure maintaining is 0.4-0.45 MPa/min; the pressure in the heat preservation and pressure maintaining process is 35-40 MPa; the time for heat preservation and pressure maintaining is 180-200 min; the temperature reduction is to inject protective gas after the hot-pressing sintering is finished and carry out furnace cooling; the end point temperature of furnace cooling is less than 200 ℃.

The carbon-silicon carbide composite powder can be prepared by adopting a conventional composite powder method, such as spray granulation compounding and the like, and other auxiliary materials and the like, such as adhesives and the like, can be added in the process.

Compared with the prior art, the invention at least has the following beneficial effects:

(1) according to the method for preparing the target blank, the sphericity and the proportion of the composite powder in the preparation process are controlled, the high-performance target blank is prepared by adopting the processes of cold pressing in advance and specific hot pressing and sintering, the prepared target blank and the back plate can be well infiltrated when being welded, the target and the back plate can be well welded, the welding bonding rate is up to 99% or more, the density is remarkably improved by more than 99%, and the yield is remarkably improved by more than 98%.

(2) According to the invention, specific powder composition is adopted, and cold pressing is firstly adopted for pretreatment, so that the powder is arranged in advance and is prepared for next sintering, and then the sintering adopts specific multi-stage heating and heat preservation sintering process to realize the preparation of the high-performance target blank, thereby solving the problem of desoldering caused by insufficient infiltration during the welding of the target blank and the back plate in the prior art.

Detailed Description

To better illustrate the invention and to facilitate the understanding of the technical solutions thereof, typical but non-limiting examples of the invention are as follows:

example 1

The embodiment provides a preparation method of a carbon silicon carbide ceramic target blank, which comprises the following steps:

the sphericity of the particles in the carbon-silicon carbide composite powder is 0.9, and the particle size is 140-150 mu m; the mass ratio of carbon to silicon carbide in the carbon-silicon carbide composite powder is 47: 53;

the pressure of the first cold pressing is 2 MPa; the time of the first cold pressing is 3 s; the pressure of the second cold pressing is 13 MPa; the pressure maintaining time of the second cold pressing is 3 min;

vacuumizing treatment is carried out before the hot-pressing sintering is started; the end point of the vacuum pumping is that the vacuum degree is 100 Pa;

the first heat preservation is that the temperature is raised to 1050 ℃ at the speed of 11 ℃/min, and then the temperature is raised to 1800 ℃ at the speed of 6 ℃/min, and the heat preservation is carried out for 60 min;

the second heat preservation is to heat up to 2100 ℃ at a speed of 4 ℃/min and preserve heat for 25 min;

the heat preservation temperature in the heat preservation and pressure maintaining process is the heat preservation temperature of the second heat preservation; the pressurizing rate in the heat preservation and pressure maintaining is 0.43 MPa/min; the pressure in the heat preservation and pressure maintaining process is 35 MPa; the time for heat preservation and pressure maintaining is 190 min; the temperature reduction is to inject protective gas after the hot-pressing sintering is finished and carry out furnace cooling; the furnace cooling end point temperature was 120 ℃.

The performance parameters and welding index of the obtained target blank are detailed in table 1.

Example 2

the sphericity of the particles in the carbon-silicon carbide composite powder is 0.8, and the particle size is 120-150 mu m; the mass ratio of carbon to silicon carbide in the carbon-silicon carbide composite powder is 2: 3;

the pressure of the first cold pressing is 1 MPa; the time of the first cold pressing is 4 s; the pressure of the second cold pressing is 10 MPa; the pressure maintaining time of the second cold pressing is 5 min;

vacuumizing treatment is carried out before the hot-pressing sintering is started; the end point of the vacuum pumping is that the vacuum degree is 80 Pa;

the first heat preservation is that the temperature is raised to 1100 ℃ at the speed of 10 ℃/min, and then the temperature is raised to 1850 ℃ at the speed of 7 ℃/min, and the heat preservation is carried out for 50 min;

the second heat preservation is to heat up to 2050 ℃ at the speed of 3 ℃/min and preserve the heat for 20 min;

the heat preservation temperature in the heat preservation and pressure maintaining process is the heat preservation temperature of the second heat preservation; the pressurizing rate in the heat preservation and pressure maintaining is 0.45 MPa/min; the pressure in the heat preservation and pressure maintaining process is 40 MPa; the time for heat preservation and pressure maintaining is 200 min; the temperature reduction is to inject protective gas after the hot-pressing sintering is finished and carry out furnace cooling; the furnace cooling end point temperature was 150 ℃.

Example 3

the sphericity of the particles in the carbon-silicon carbide composite powder is 1, and the particle size is 170-180 mu m; the mass ratio of carbon to silicon carbide in the carbon-silicon carbide composite powder is 1: 1;

the pressure of the first cold pressing is 1.5 MPa; the time of the first cold pressing is 2 s; the pressure of the second cold pressing is 15 MPa; the pressure maintaining time of the second cold pressing is 2 min;

vacuumizing treatment is carried out before the hot-pressing sintering is started; the end point of the vacuum pumping is that the vacuum degree is 75 Pa;

the first heat preservation is to heat up to 1000 ℃ at a speed of 12 ℃/min, then heat up to 1900 ℃ at a speed of 5 ℃/min, and preserve heat for 55 min;

the second heat preservation is to heat up to 2150 ℃ at a speed of 5 ℃/min and preserve heat for 30 min;

the heat preservation temperature in the heat preservation and pressure maintaining process is the heat preservation temperature of the second heat preservation; the pressurizing rate in the heat preservation and pressure maintaining is 0.4 MPa/min; the pressure in the heat preservation and pressure maintaining process is 35 MPa; the time for heat preservation and pressure maintaining is 180 min; the temperature reduction is to inject protective gas after the hot-pressing sintering is finished and carry out furnace cooling; the furnace cooling end point temperature was 175 ℃.

Comparative example 1

The difference from the example 1 is only that the carbon powder and the silicon carbide powder with the same mass ratio as the composite powder are mixed and then cold-pressed, and the performance parameters and the welding index of the obtained target blank are detailed in the table 1. The cold pressed blank will crack directly after cold isostatic pressing, and the next operation cannot be carried out. Or a certain amount of binder is added into the mixed powder, but the cracking problem still occurs after cold isostatic pressing, and the next operation cannot be carried out.

Comparative example 2

The only difference from example 1 is that the sphericity of the particles in the carbon-silicon carbide composite powder was 0.5, and the performance parameters and the welding index of the resulting target blank are detailed in table 1.

Comparative example 3

The only difference from example 1 is that the particle size of the particles in the carbon-silicon carbide composite powder is 200-300 μm, and the performance parameters and welding index of the obtained target blank are detailed in Table 1.

Comparative example 4

The difference from example 1 is that the cold pressing is not carried out, the subsequent sintering is directly carried out after the die filling, and the performance parameters and welding indexes of the obtained target blank are detailed in table 1.

Comparative example 5

The only difference from example 1 is that the first cold pressing was not carried out, i.e. the second cold pressing was carried out directly, and the performance parameters and the welding index of the obtained target blank are detailed in table 1.

Comparative example 6

The only difference from example 1 is that in the first heat preservation, the temperature is directly raised to 1850 ℃ at a rate of 11 ℃/min, i.e. no step temperature raising is carried out, and the performance parameters and welding indexes of the obtained target blank are detailed in table 1.

Comparative example 7

The only difference from example 1 is that the temperature rise rate of the second heat preservation is 12 ℃/min, and the performance parameters and welding indexes of the obtained target blank are detailed in table 1.

The target blank and the back plate are welded by brazing, the solder is high-purity indium, the target blank and the back plate are placed on a welding platform and heated to the required welding temperature, the welding surface of the target blank and the back plate is fully soaked by ultrasonic waves, and the target blank and the back plate are buckled together after being soaked. And after the temperature is cooled to the room temperature, the welding is finished.

TABLE 1

	Wettability	Weld bonding rate/%)	Density/%	Yield per cent
					Example 1	100% infiltration	100％	99.5％	100％
Example 2	100% infiltration	99.8％	99.3％	100％
					Example 3	100% infiltration	99.8％	99.5％	100％
Comparative example 1	/	/	/	/
					Comparative example 2	95% infiltration	94.8％	97.6％	50％
Comparative example 3	95% infiltration	94.2％	98.6％	70％
					Comparative example 4	90% infiltration	89.1％	97.0％	70％
Comparative example 5	95% infiltration	94.5％	98.7％	90％
					Comparative example 6	90% infiltration	98.3％	97.8％	80％
Comparative example 7	95% infiltration	93.7％	98.4％	90％

According to the results of the embodiment and the comparative example, the target blank preparation method provided by the invention has the advantages that the grains can be better recombined and fused in the sintering process through controlling the sphericity and the proportion of the raw materials in the preparation process, the preparation of the high-performance target blank is realized by adopting the pre-cold pressing and hot pressing sintering modes, the prepared target blank and the back plate can be well infiltrated when being welded, the good welding of the target and the back plate can be further ensured, the welding bonding rate is up to 99% or more, the density is remarkably improved by more than 99%, and the yield is remarkably improved by more than 98%.

The applicant declares that the present invention illustrates the detailed structural features of the present invention through the above embodiments, but the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must be implemented depending on the above detailed structural features. It should be understood by those skilled in the art that any modifications of the present invention, equivalent substitutions of selected components of the present invention, additions of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. The preparation method of the carbon silicon carbide ceramic target blank is characterized by comprising the following steps of:

filling carbon-silicon carbide composite powder into a mold, performing cold pressing, and then sequentially performing hot-pressing sintering and cooling to obtain the carbon-silicon carbide ceramic target blank;

2. The method according to claim 1, wherein the mass ratio of carbon to silicon carbide in the carbon-silicon carbide composite powder is (1-2) to (1-3).

3. The production method according to claim 1 or 2, wherein the cold pressing is die pressing of the composite powder after die filling;

preferably, the cold pressing comprises a first cold pressing and a second cold pressing carried out in sequence;

preferably, the pressure of the first cold pressing is < 3 MPa;

preferably, the time of the first cold pressing is 2-4 s;

preferably, the pressure of the second cold pressing is 10-15 MPa;

preferably, the dwell time of the second cold pressing is 2-5 min.

4. The production method according to any one of claims 1 to 3, wherein evacuation treatment is performed before the hot press sintering is started;

preferably, the end point of the vacuum pumping is that the vacuum degree is less than or equal to 100 Pa.

5. The method according to any one of claims 1-4, wherein the first temperature is raised to 1100 ℃ at 10-12 ℃/min, then raised to 1800 ℃ at 1900 ℃ at 5-7 ℃/min, and then maintained for 50-60 min.

6. The method according to any one of claims 1 to 5, wherein the second heat-preservation is performed by raising the temperature to 2050-.

7. The production process according to any one of claims 1 to 6, wherein the incubation temperature in the incubation and holding is the incubation temperature of the second incubation.

8. The production process according to any one of claims 1 to 7, wherein the pressurization rate in the heat-keeping and pressure-holding is from 0.4 to 0.45 MPa/min;

preferably, the pressure in the heat preservation and pressure maintaining process is 35-40 MPa;

preferably, the time for heat preservation and pressure maintaining is 180-200 min.

9. The preparation method according to any one of claims 1 to 8, wherein the temperature reduction is carried out by injecting a protective gas after the hot-press sintering is finished and carrying out furnace cooling;

preferably, the furnace cooling end point temperature is < 200 ℃.

10. The method of any one of claims 1 to 9, comprising the steps of:

the first heat preservation is to heat up to 1100 ℃ at the speed of 10-12 ℃/min and then to 1800 ℃ at the speed of 1800 ℃ and 1900 ℃ at the speed of 5-7 ℃/min, and then to preserve heat for 50-60 min;

the second heat preservation is to heat up to 2050-;