A porous cermet composite material and a method for producing the same

Abstract

The application discloses a kind of porous cermet composite materials, the composite material is composed of the following volume fraction of ingredients: 24%~42% WMoTaNb alloy phase, 18%~26% alumina-zirconia composite ceramic phase, the rest is porosity, in addition, the application also provides the preparation method of porous cermet composite material, equal atomic ratio spherical W, Mo, Ta, Nb powder and stearic acid particles are made into green body after heating and debinding and pre-sintering, then sintered with alumina-zirconia composite ceramic plate, obtain porous cermet composite material.The porous cermet composite material of the application realizes the uniform, continuous distribution of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase and porosity, simultaneously has the performance advantage of porous metal material, WMoTaNb refractory high-entropy alloy and alumina-zirconia composite ceramic three, has very broad application prospect in high-temperature heat exchange, aerospace and other fields.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of cermet composite materials, and particularly relates to a porous cermet composite material and a preparation method thereof. BACKGROUND

[0002] Metallic porous materials have special void types and pore structures, and have special functions such as purification separation, noise reduction, adsorption and slow release, and efficient heat conduction in addition to the characteristics of metal materials. The metallic porous materials are widely used in filtration and separation equipment in the fields of energy and chemical industry, aerospace, metallurgical building materials, weapons and ships, machinery and vehicles, and biological medicine, and are key basic materials for improving quality and efficiency, energy saving and emission reduction, pollution control and comprehensive utilization of resources and energy in related industrial engineering.

[0003] High-entropy alloys composed of refractory metal elements (such as V, Nb, Ta, Mo, W, Ti, Zr and Hf) are called refractory high-entropy alloys. High melting point leads to excellent performance of refractory high-entropy alloys at high temperature, becoming high-temperature alloys with industrial application potential. Refractory high-entropy alloys have high hardness, high strength and good phase stability at high temperature, showing high-temperature strength and other properties that existing alloys cannot match, thus having great application potential in high-temperature environments.

[0004] Cermet composite materials exhibit excellent characteristics such as high-temperature red hardness, corrosion resistance and oxidation resistance in engineering applications, and become ideal alternative materials for traditional hard alloys, and are widely used in the fields of automobile manufacturing, aviation and mold manufacturing. Zirconia ceramics have more excellent physical and mechanical properties than general ceramics, and use the characteristics of crystal type transformation in the sintering process to improve the strength and fracture toughness of the material, but have poor high-temperature mechanical properties and high cost. Alumina ceramics have good room temperature mechanical properties, high thermal expansion coefficient, good chemical stability and low price. Therefore, alumina-zirconia composite ceramics can have the advantages of each phase, achieving the purpose of reducing cost and improving performance.

[0005] Porous refractory high-entropy alloy / alumina-zirconia ceramic composite material can have the special functions of the above-mentioned metallic porous material, the good high-temperature performance of the refractory high-entropy alloy, and the high-temperature resistance and high hardness of the ceramic, and has very broad application prospects.

[0006] Therefore, it is of great theoretical significance and practical application value to explore a reasonable, efficient and low-cost method to successfully prepare a porous cermet composite material. SUMMARY

[0007] The technical problem solved by the present application is to provide a porous metal ceramic composite material to overcome the shortcomings of the prior art.

[0008] To solve the above technical problem, the present application adopts the technical scheme of a porous metal ceramic composite material, characterized in that the composite material is composed of the following components in volume fraction: 24-42% WMoTaNb alloy phase, 18-26% alumina-zirconia composite ceramic phase, and the balance being pores.

[0009] The porous metal ceramic composite material of the present application has the performance advantages of porous metal material, WMoTaNb refractory high-entropy alloy, and alumina-zirconia composite ceramic, and has a very broad application prospect in the fields of high-temperature heat exchange, aerospace, etc.

[0010] The porous metal ceramic composite material described above is characterized in that the composite material is composed of the following components in volume fraction: 27.3-40.1% WMoTaNb alloy phase, 21.6-24.8% alumina-zirconia composite ceramic phase, and the balance being pores.

[0011] The porous metal ceramic composite material described above is characterized in that the composite material is composed of the following components in volume fraction: 37.9% WMoTaNb alloy phase, 23.7% alumina-zirconia composite ceramic phase, and the balance being pores.

[0012] In addition, the present application also provides a method for preparing a porous metal ceramic composite material, characterized in that the method comprises the following steps:

[0013] Step one, porous WMoTaNb alloy framework preparation: spherical W, Mo, Ta, and Nb powders with equal atomic ratio are added to anhydrous ethanol together with stearic acid particles, and are fully stirred and mixed uniformly under heating water bath conditions, dried, and then pressed to form a green body, which is then subjected to heating, degreasing, and pre-sintering, and the porous WMoTaNb alloy framework is obtained after furnace cooling;

[0014] Step two, sintering: the porous WMoTaNb alloy framework obtained in step one is placed on an alumina-zirconia composite ceramic plate, and is sintered under vacuum conditions at a heating rate of 8-14℃ / min to 1900-2000℃, and then held for 5-7h, and the porous metal ceramic composite material is obtained after furnace cooling.

[0015] The method has the advantages that the adding amount of the stearic acid in the step one is 0.8%-1.2% of the total mass of the W, Mo, Ta and Nb powders, the adding amount of the stearic acid is controlled, and the prepared porous WMoTaNb alloy framework has proper porosity.

[0016] The method has the advantages that the forming mode of the step one is cold isostatic pressing, the pressure is 200-240 MPa, and the pressure maintaining time is 1-4 min, the parameters of the forming are controlled, the close packing between the particles is promoted, the density and the strength of the green body are improved, the appearance integrity of the green body is ensured, and the excessive compression between the particles caused by the excessively high forming pressure or the excessively long pressure maintaining time is avoided.

[0017] The method has the advantages that the heating, the debinding and the pre-sintering in the step one are carried out as follows: the heating is carried out at a heating rate of 1-3 ℃ / min to 350-500 ℃, and then the heating is maintained for 3-5 h to carry out the heating debinding; and then the heating is carried out at a heating rate of 8-12 ℃ / min to 1100-1300 ℃, and then the heating is maintained for 1-3 h to carry out the pre-sintering, the heating and the maintaining at a low temperature are carried out first, the added stearic acid is completely removed, other impurity phases are not introduced, the proportion of the phases is not affected, and the mechanical properties are not reduced, then the heating is carried out at a high temperature at a fast heating rate, the bonding between the powders is ensured by the element diffusion, the strength of the porous WMoTaNb alloy framework is not low after the complete debinding, and the subsequent sintering process is not difficult to carry out.

[0018] The method has the advantages that the heating, the debinding and the pre-sintering in the step one are carried out as follows: the heating, the debinding and the pre-sintering in the step one and the sintering in the step two are carried out in a vacuum sintering furnace, the vacuum degree in the vacuum sintering furnace is not more than 8.0*10 -2 Pa, and the influence of other gases on the material is prevented.

[0019] The method has the advantages that the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework in the step two is 0.6-1.5:1, the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is controlled, the molten alumina-zirconia composite ceramic plate cannot completely fill the porous WMoTaNb alloy framework, and the prepared porous metal ceramic composite material has the optimal porosity ratio.

[0020] Compared with the prior art, the method has the following advantages:

[0021] 1. The porous cermet composite material of the present application has the performance advantages of the three of the porous metal material, the WMoTaNb refractory high-entropy alloy and the alumina-zirconia composite ceramic, and has a very broad application prospect in the fields of high-temperature heat exchange, aerospace, etc.

[0022] 2. The W, Mo, Ta and Nb powders of the present application are spherical, and the original packing porosity of the spherical particle powder can be well preserved in the sintering process, so as to ensure that the porous refractory high-entropy alloy framework can still maintain the uniform and continuous porosity after further densification in the sintering process, which is conducive to the infiltration of the molten alumina-zirconia composite ceramic into the interior of the porous refractory high-entropy alloy framework through the capillary force, so as to realize the uniform and continuous distribution of the WMoTaNb alloy phase, the alumina-zirconia composite ceramic phase and the porosity, significantly simplify the process flow, and the preparation method is simple, easy to realize, short in flow and low in cost.

[0023] 3. The mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 0.6-1.5, which can ensure that the infiltrated molten alumina-zirconia composite ceramic plate cannot completely fill the porous WMoTaNb alloy framework, so that the porous cermet composite material has the best porosity ratio.

[0024] The technical solutions of the present application will be further described in detail through the following examples. DETAILED DESCRIPTION

[0025] Example 1

[0026] This example includes the following steps:

[0027] Step one, preparation of the porous WMoTaNb alloy framework: spherical W, Mo, Ta and Nb powders with equal atomic ratio and stearic acid particles are added to anhydrous ethanol, and are fully stirred and mixed uniformly under the condition of a heated water bath, and then are dried and cold isostatic pressed under the pressure of 220 MPa and the pressure holding time of 3 min to obtain a green body, which is placed into a vacuum sintering furnace with the vacuum degree of 7.2*10 -3 Pa, heated to 400℃ at the heating rate of 2℃ / min, and then heated to 1200℃ at the heating rate of 10℃ / min for 2h for pre-sintering, and then cooled in the furnace to obtain the porous WMoTaNb alloy framework; the addition amount of the stearic acid is 1.0% of the total mass of the W, Mo, Ta and Nb powders;

[0028] Step two, sintering: the porous WMoTaNb alloy framework obtained in step one is placed on the alumina-zirconia composite ceramic plate, and is sintered in the vacuum sintering furnace with the vacuum degree of 6.1*10 -3The porous metal ceramic composite material is obtained by sintering in a vacuum sintering furnace of Pa at a temperature rising speed of 10℃ / min to 1950℃ for 6h, and then cooling in the furnace; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 0.8:1.

[0029] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase and pores, wherein the volume fraction of each component is: WMoTaNb alloy phase 30.1%, alumina-zirconia composite ceramic phase 25.7%, and pores 44.2%; the room temperature compressive strength of the porous metal ceramic composite material is 122MPa.

[0030] Example 2

[0031] The embodiment comprises the following steps:

[0032] Step one, preparation of porous WMoTaNb alloy framework: spherical W, Mo, Ta and Nb powders with equal atomic ratio are added to anhydrous ethanol with stearic acid particles, and then mixed uniformly under the condition of heating water bath and sufficient stirring, and then dried and cold isostatic pressed under the pressure of 230MPa and the pressure holding time of 3min to obtain a green body, which is placed in a vacuum sintering furnace of Pa with the vacuum degree of 7.2×10 -3 The porous WMoTaNb alloy framework is obtained by heating in a vacuum sintering furnace of Pa at a temperature rising speed of 2℃ / min to 400℃ for 4h for heating and degreasing, and then heating at a temperature rising speed of 10℃ / min to 1200℃ for 2h for pre-sintering, and then cooling in the furnace; the addition amount of stearic acid is 1.2% of the total mass of W, Mo, Ta and Nb powders;

[0033] Step two, sintering: the porous WMoTaNb alloy framework obtained in step one is placed on the alumina-zirconia composite ceramic plate, and then sintered in a vacuum sintering furnace of Pa with the vacuum degree of 6.1×10 -3 The porous metal ceramic composite material is obtained by sintering in a vacuum sintering furnace of Pa at a temperature rising speed of 10℃ / min to 1940℃ for 6h, and then cooling in the furnace; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 0.9:1.

[0034] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase and pores, wherein the volume fraction of each component is: WMoTaNb alloy phase 35.9%, alumina-zirconia composite ceramic phase 22.3%, and pores 41.8%; the room temperature compressive strength of the porous metal ceramic composite material is 167MPa.

[0035] Example 3

[0036] The embodiment comprises the following steps:

[0037] Step one, preparation of porous WMoTaNb alloy framework: add spherical W, Mo, Ta, Nb powders with equal atomic ratio and stearic acid particles into anhydrous ethanol, mix uniformly under sufficient stirring in a heated water bath, and then perform cold isostatic pressing at a pressure of 220 MPa and a pressure holding time of 3 min after drying to obtain a green body, and place the green body into a vacuum sintering furnace with a vacuum degree of 4.4*10 -3 Pa, heat to 410℃ at a heating rate of 2℃ / min, and then heat to 1200℃ at a heating rate of 10℃ / min for 2h of heat debinding and pre-sintering, and then cool down with the furnace to obtain a porous WMoTaNb alloy framework; the addition amount of stearic acid is 0.8% of the total mass of W, Mo, Ta, and Nb powders;

[0038] Step two, sintering: place the porous WMoTaNb alloy framework obtained in step one on an alumina-zirconia composite ceramic plate, and perform sintering in a vacuum sintering furnace with a vacuum degree of 5.2*10 -3 Pa at a heating rate of 10℃ / min to 1950℃ for 6h of sintering, and then cool down with the furnace to obtain a porous metal ceramic composite material; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 1:1.

[0039] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of a WMoTaNb alloy phase, an alumina-zirconia composite ceramic phase, and pores, wherein the volume fraction of each component is: 33.3% for the WMoTaNb alloy phase, 18.2% for the alumina-zirconia composite ceramic phase, and 48.5% for the pores, and the room temperature compressive strength of the porous metal ceramic composite material is 117MPa.

[0040] Embodiment 4

[0041] The embodiment comprises the following steps:

[0042] Step one, preparation of porous WMoTaNb alloy framework: add spherical W, Mo, Ta, Nb powders with equal atomic ratio and stearic acid particles into anhydrous ethanol, mix uniformly under sufficient stirring in a heated water bath, and then perform cold isostatic pressing at a pressure of 220 MPa and a pressure holding time of 3 min after drying to obtain a green body, and place the green body into a vacuum sintering furnace with a vacuum degree of 4.4*10 -3The porous WMoTaNb alloy framework is obtained by heating and debinding in a vacuum sintering furnace at 400℃ for 4h at a heating rate of 2℃ / min, and then pre-sintering at 1200℃ for 2h at a heating rate of 10℃ / min, and then cooling in the furnace; the stearic acid is added in an amount of 1.0% of the total mass of the W, Mo, Ta, and Nb powders;

[0043] Step two, sintering: the porous WMoTaNb alloy framework obtained in step one is placed on the alumina-zirconia composite ceramic plate, and sintering is performed in a vacuum sintering furnace at 1900℃ for 7h at a heating rate of 8℃ / min, and then cooling in the furnace to obtain the porous metal ceramic composite material; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 1.2:1. -3 Pa, and sintering is performed in a vacuum sintering furnace at 1900℃ for 7h at a heating rate of 8℃ / min, and then cooling in the furnace to obtain the porous metal ceramic composite material; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 1.2:1.

[0044] It is detected that the porous metal ceramic composite material prepared in this embodiment is composed of a WMoTaNb alloy phase, an alumina-zirconia composite ceramic phase, and pores, wherein the volume fractions of the respective components are: the WMoTaNb alloy phase 24.2%, the alumina-zirconia composite ceramic phase 25.8%, and the pores 50.0%, and the room temperature compressive strength of the porous metal ceramic composite material is 107MPa.

[0045] Example 5

[0046] This embodiment includes the following steps:

[0047] Step one, preparation of a porous WMoTaNb alloy framework: spherical W, Mo, Ta, and Nb powders with an equal atomic ratio are added to anhydrous ethanol together with stearic acid particles, and the mixture is stirred and mixed uniformly under the condition of a heated water bath, and then dried and cold isostatic pressed at a pressure of 240MPa for 1min to obtain a green body, and the green body is placed in a vacuum sintering furnace with a vacuum degree of 7.2x10 -3 The porous WMoTaNb alloy framework is obtained by heating and debinding in a vacuum sintering furnace at 400℃ for 4h at a heating rate of 2℃ / min, and then pre-sintering at 1200℃ for 2h at a heating rate of 10℃ / min, and then cooling in the furnace; the stearic acid is added in an amount of 1.0% of the total mass of the W, Mo, Ta, and Nb powders;

[0048] Step two, sintering: the porous WMoTaNb alloy framework obtained in step one is placed on the alumina-zirconia composite ceramic plate, and sintering is performed in a vacuum sintering furnace at 1900℃ for 7h at a heating rate of 8℃ / min, and then cooling in the furnace to obtain the porous metal ceramic composite material; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 1.2:1. -3The porous metal ceramic composite material is obtained by sintering in a vacuum sintering furnace of Pa at a heating rate of 14℃ / min to 2000℃ and keeping for 5h, and then cooling in the furnace; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 0.8:1.

[0049] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase and pores, wherein the volume fraction of each component is: WMoTaNb alloy phase 41.3%, alumina-zirconia composite ceramic phase 18.3%, and pores 40.4%, and the room temperature compressive strength of the porous metal ceramic composite material is 142MPa.

[0050] Example 6

[0051] The embodiment comprises the following steps:

[0052] Step one, preparation of porous WMoTaNb alloy framework: spherical W, Mo, Ta and Nb powders with equal atomic ratio are added to anhydrous ethanol with stearic acid particles, and then mixed uniformly under the condition of heating water bath and sufficient stirring, and then dried and cold isostatic pressed under the pressure of 220MPa and the pressure keeping time of 3min to obtain a green body, and then the green body is put into a vacuum sintering furnace of Pa with the vacuum degree of 7.2×10 -3 The porous WMoTaNb alloy framework is obtained by heating in a vacuum sintering furnace of Pa at a heating rate of 1℃ / min to 500℃ and keeping for 5h for heating and degreasing, and then heating at a heating rate of 8℃ / min to 1300℃ and keeping for 3h for pre-sintering, and then cooling in the furnace; the addition amount of stearic acid is 1.0% of the total mass of W, Mo, Ta and Nb powders;

[0053] Step two, sintering: the porous WMoTaNb alloy framework obtained in step one is placed on the alumina-zirconia composite ceramic plate, and then sintered in a vacuum sintering furnace of Pa with the vacuum degree of 6.1×10 -3 The porous metal ceramic composite material is obtained by sintering in a vacuum sintering furnace of Pa at a heating rate of 14℃ / min to 2000℃ and keeping for 5h, and then cooling in the furnace; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 0.8:1.

[0054] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase and pores, wherein the volume fraction of each component is: WMoTaNb alloy phase 41.3%, alumina-zirconia composite ceramic phase 18.3%, and pores 40.4%, and the room temperature compressive strength of the porous metal ceramic composite material is 142MPa.

[0055] Example 7

[0056] The embodiment comprises the following steps:

[0057] Step one, preparation of porous WMoTaNb alloy framework: add spherical W, Mo, Ta, Nb powders with equal atomic ratio and stearic acid particles into anhydrous ethanol, mix uniformly under sufficient stirring in a heated water bath, and then perform cold isostatic pressing at a pressure of 220 MPa and a pressure holding time of 3 min after drying to obtain a green body; place the green body into a vacuum sintering furnace with a vacuum degree of 7.2 x 10 -3 Pa, heat to 350℃ at a heating rate of 3℃ / min, and then heat to 1100℃ at a heating rate of 12℃ / min for 1h for pre-sintering, and then cool down in the furnace to obtain the porous WMoTaNb alloy framework; the addition amount of stearic acid is 1.0% of the total mass of W, Mo, Ta, and Nb powders;

[0058] Step two, sintering: place the porous WMoTaNb alloy framework obtained in step one on an alumina-zirconia composite ceramic plate, and then perform sintering in a vacuum sintering furnace with a vacuum degree of 6.1 x 10 -3 Pa at a heating rate of 10℃ / min to 1950℃ for 6h, and then cool down in the furnace to obtain the porous metal ceramic composite material; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 0.8:1.

[0059] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase, and pores, wherein the volume fraction of each component is: WMoTaNb alloy phase 32.6%, alumina-zirconia composite ceramic phase 23.2%, and pores 44.2%, and the room temperature compressive strength of the porous metal ceramic composite material is 177 MPa.

[0060] Embodiment 8

[0061] The embodiment comprises the following steps:

[0062] Step one, preparation of porous WMoTaNb alloy framework: add spherical W, Mo, Ta, Nb powders with equal atomic ratio and stearic acid particles into anhydrous ethanol, mix uniformly under sufficient stirring in a heated water bath, and then perform cold isostatic pressing at a pressure of 220 MPa and a pressure holding time of 3 min after drying to obtain a green body; place the green body into a vacuum sintering furnace with a vacuum degree of 7.2 x 10 -3In a vacuum sintering furnace, the material is heated to 400°C at a heating rate of 2°C / min and held for 4 hours for degreasing. Then, it is heated to 1200°C at a heating rate of 10°C / min and held for 2 hours for pre-sintering. After cooling in the furnace, a porous WMoTaNb alloy skeleton is obtained. The amount of stearic acid added is 1.0% of the total mass of W, Mo, Ta, and Nb powders.

[0063] Step 2, Sintering: The porous WMoTaNb alloy framework obtained in Step 1 is placed on an alumina-zirconia composite ceramic plate and sintered under a vacuum of 6.1 × 10⁻⁶. -3 In a vacuum sintering furnace of Pa, the temperature was increased to 1950℃ at a heating rate of 10℃ / min and held for 6 hours for sintering. After cooling in the furnace, a porous metal-ceramic composite material was obtained. The mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy skeleton was 0.6:1.

[0064] Testing revealed that the porous metal-ceramic composite material prepared in this embodiment consists of a WMoTaNb alloy phase, an alumina-zirconia composite ceramic phase, and pores. The volume fractions of each component are as follows: WMoTaNb alloy phase 28.6%, alumina-zirconia composite ceramic phase 20.2%, and pores 51.2%. The room temperature compressive strength of the porous metal-ceramic composite material is 102 MPa.

[0065] Example 9

[0066] This embodiment includes the following steps:

[0067] Step 1: Preparation of porous WMoTaNb alloy framework: Equivalent atomic ratio spherical W, Mo, Ta, and Nb powders and stearic acid particles were added to anhydrous ethanol and thoroughly mixed under heating water bath conditions. After drying, the mixture was cold isostatically pressed at a pressure of 220 MPa for 3 minutes to obtain a green compact. The green compact was then placed in a vacuum of 7.2 × 10⁻⁶ m³ / h. -3 In a vacuum sintering furnace, the material is heated to 400°C at a heating rate of 2°C / min and held for 4 hours for degreasing. Then, it is heated to 1200°C at a heating rate of 10°C / min and held for 2 hours for pre-sintering. After cooling in the furnace, a porous WMoTaNb alloy skeleton is obtained. The amount of stearic acid added is 1.0% of the total mass of W, Mo, Ta, and Nb powders.

[0068] Step 2, Sintering: The porous WMoTaNb alloy framework obtained in Step 1 is placed on an alumina-zirconia composite ceramic plate and sintered under a vacuum of 6.1 × 10⁻⁶. -3The porous metal ceramic composite material is obtained by sintering in a vacuum sintering furnace of Pa at a temperature rising speed of 10℃ / min to 1950℃ for 6h, and then cooling in the furnace; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 1.5:1.

[0069] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase and pores, wherein the volume fraction of each component is: WMoTaNb alloy phase 31.5%, alumina-zirconia composite ceramic phase 24.8%, and pores 43.7%; the room temperature compressive strength of the porous metal ceramic composite material is 153MPa.

[0070] Embodiment 10

[0071] The embodiment comprises the following steps:

[0072] Step one, preparation of porous WMoTaNb alloy framework: spherical W, Mo, Ta and Nb powders with equal atomic ratio are added to anhydrous ethanol with stearic acid particles, and then mixed uniformly under the condition of heating water bath and sufficient stirring, and then dried and cold isostatic pressed under the pressure of 220MPa for 3min to obtain a green body, which is then put into a vacuum sintering furnace of Pa with the vacuum degree of 7.2×10 -3 The porous WMoTaNb alloy framework is obtained by heating in a vacuum sintering furnace of Pa at a temperature rising speed of 2℃ / min to 400℃ for 4h for heating and degreasing, and then heating at a temperature rising speed of 10℃ / min to 1200℃ for 2h for pre-sintering, and then cooling in the furnace; the addition amount of stearic acid is 1.0% of the total mass of W, Mo, Ta and Nb powders;

[0073] Step two, sintering: the porous WMoTaNb alloy framework obtained in step one is placed on the alumina-zirconia composite ceramic plate, and then sintered in a vacuum sintering furnace of Pa with the vacuum degree of 6.1×10 -3 The porous metal ceramic composite material is obtained by sintering in a vacuum sintering furnace of Pa at a temperature rising speed of 10℃ / min to 1950℃ for 6h, and then cooling in the furnace; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 0.6:1.

[0074] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase and pores, wherein the volume fraction of each component is: WMoTaNb alloy phase 42%, alumina-zirconia composite ceramic phase 21.6%, and pores 36.4%; the room temperature compressive strength of the porous metal ceramic composite material is 149MPa.

[0075] Embodiment 11

[0076] The embodiment comprises the following steps:

[0077] Step one, preparation of porous WMoTaNb alloy framework: spherical W, Mo, Ta, Nb powders with equal atomic ratio and stearic acid particles are added into anhydrous ethanol, and are stirred uniformly under the condition of heated water bath, and after drying, green compacts are obtained by cold isostatic pressing under the pressure of 220 MPa and the pressure holding time of 3 min, and the green compacts are placed into a vacuum sintering furnace with the vacuum degree of 7.2×10 -3 Pa, and are heated to 400℃ at the heating rate of 2℃ / min and then are kept for 4h to perform heating debinding, and then are heated to 1200℃ at the heating rate of 10℃ / min and then are kept for 2h to perform presintering, and after furnace cooling, the porous WMoTaNb alloy framework is obtained; the addition amount of the stearic acid is 1.0% of the total mass of the W, Mo, Ta, Nb powders;

[0078] Step two, sintering: the porous WMoTaNb alloy framework obtained in step one is placed on an alumina-zirconia composite ceramic plate, and is sintered in a vacuum sintering furnace with the vacuum degree of 6.1×10 -3 Pa at the heating rate of 10℃ / min to 1950℃ and then is kept for 6h, and after furnace cooling, the porous metal ceramic composite material is obtained; the mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework is 0.7:1.

[0079] It is detected that the porous metal ceramic composite material prepared in the embodiment is composed of WMoTaNb alloy phase, alumina-zirconia composite ceramic phase and pores, wherein the volume fraction of each component is: WMoTaNb alloy phase 40.1%, alumina-zirconia composite ceramic phase 22.5%, and pores 37.4%, and the room temperature compressive strength of the porous metal ceramic composite material is 147MPa.

[0080] The above is only a preferred embodiment of the present application, and does not limit the present application. Any simple modification, change and equivalent change of the above embodiment according to the technical essence of the present application are still within the protection scope of the technical solution of the present application.

Claims

1. A porous cermet composite material, characterized by, The composite material is composed of the following components in volume fraction: 24-42% WMoTaNb alloy phase, 18-26% alumina-zirconia composite ceramic phase, and the balance being pores. The method for preparing the composite material comprises the following steps: Step one: preparation of a porous WMoTaNb alloy framework: spherical W, Mo, Ta and Nb powders with equal atomic ratio and stearic acid particles are added to anhydrous ethanol, and the mixture is stirred and mixed uniformly under the condition of a heated water bath, dried, and then pressed to form a green body, which is then subjected to heating, degreasing and pre-sintering, and the porous WMoTaNb alloy framework is obtained after furnace cooling; the process of heating, degreasing and pre-sintering is as follows: heating at a temperature increasing rate of 1-3℃ / min to 350-500℃, holding for 3-5h for heating and degreasing, and then heating at a temperature increasing rate of 8-12℃ / min to 1100-1300℃, holding for 1-3h for pre-sintering; Step two: sintering: the porous WMoTaNb alloy framework obtained in step one is placed on an alumina-zirconia composite ceramic plate, and sintering is performed under vacuum at a temperature increasing rate of 8-14℃ / min to 1900-2000℃, holding for 5-7h, and the porous metal ceramic composite material is obtained after furnace cooling.

2. The porous cermet composite of claim 1, wherein The composite material is composed of the following components in volume fraction: 27.3-40.1% WMoTaNb alloy phase, 21.6-24.8% alumina-zirconia composite ceramic phase, and the balance being pores.

3. The porous cermet composite of claim 1, wherein, The composite material is composed of the following components in volume fraction: 37.9% WMoTaNb alloy phase, 23.7% alumina-zirconia composite ceramic phase, and the balance being pores.

4. The porous cermet composite of claim 1, wherein, The stearic acid is added in step one in an amount of 0.8-1.2% of the total mass of the W, Mo, Ta and Nb powders.

5. The porous cermet composite of claim 1, wherein, The pressing forming in step one is cold isostatic pressing at a pressure of 200-240MPa and a pressure holding time of 1-4min.

6. The porous cermet composite of claim 1, wherein, The heating debinding and pre-sintering in step one and the sintering in step two are both carried out in a vacuum sintering furnace, and the vacuum degree in the vacuum sintering furnace is not more than 8.0x10 -2 Pa.

7. The porous cermet composite of claim 1, wherein The mass ratio of the alumina-zirconia composite ceramic plate to the porous WMoTaNb alloy framework in step two is 0.6-1.5:1.