Diamond and copper high-thermal-conductivity composite material and preparation method thereof

Abstract

The invention relates to the field of high-thermal-conductivity composite materials, in particular to a diamond and copper high-thermal-conductivity composite material and a preparation method thereof. The method is used for solving the problems that an existing diamond and copper high-thermal-conductivity composite material is low in density and thermal conductivity. The composite material is prepared by taking chromium-tungsten-coated diamond and aluminum nitride-coated copper powder as matrixes and adding lanthanum-magnesium-titanium-aluminum alloy powder, the diamond is firstly subjected to surface treatment, the surface of the diamond is plated with tungsten and chromium, the wettability of the diamond and copper can be enhanced through tungsten and chromium coating, the interface thermal resistance of the diamond and the copper matrixes is reduced, and the heat resistance of the diamond and the copper matrixes is improved; the surface of copper powder is coated with aluminum nitride to form a heat conduction network, lanthanum magnesium titanium aluminum alloy powder reduces the wetting angle of copper and diamond through alloying, interface gaps are filled, heat resistance is reduced, and the heat conductivity of the composite material is improved; all the components jointly improve the heat conduction performance of the composite material, and the requirements of the fields of high-power electronics, aerospace and the like for efficient heat dissipation are met.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-thermal-conductivity composite materials, and particularly relates to a diamond-copper high-thermal-conductivity composite material and a preparation method thereof. BACKGROUND

[0002] In recent years, composite materials have attracted extensive attention due to their excellent comprehensive performance. In particular, composite thermal conductive materials combining the advantages of diamond and copper have gradually become a research hotspot. Diamond is a highly thermal conductive material with extremely low thermal resistance and high thermal conductivity, while copper is also a commonly used highly thermal conductive metal with good electrical conductivity and thermal conductivity. If the two can be effectively combined, a new type of thermal conductive material with excellent thermal conductivity and higher mechanical strength is expected to be developed. However, the existing diamond-copper composite materials have low density and low thermal conductivity due to weak interface bonding between the two. The present application provides a diamond-copper high-thermal-conductivity composite material and a preparation method thereof, which has a high industrial application prospect. SUMMARY

[0003] In order to overcome the above technical problems, the purpose of the present application is to provide a diamond-copper high-thermal-conductivity composite material and a preparation method thereof, which solves the problem of low density and low thermal conductivity of the existing diamond-copper high-thermal-conductivity composite materials.

[0004] The purpose of the present application can be achieved by the following technical solutions: In a first aspect, the present application provides a diamond-copper high-thermal-conductivity composite material, comprising the following weight parts: 30-60 parts of chromium-tungsten coated diamond, 30-60 parts of aluminum nitride coated copper powder, and 15-20 parts of lanthanum-magnesium-titanium-aluminum alloy powder; The chromium-tungsten coated diamond is prepared by the following steps: Step A1: diamond, sodium hydroxide solution are added to a three-necked flask equipped with a thermometer and a magnetic stirrer, and then transferred to a water bath, stirred at 90℃ for 15min, washed with deionized water until the pH of the washing liquid is 7, filtered, and the alkali-washed diamond is obtained; Step A2: the alkali-washed diamond and hydrochloric acid solution are added to a three-necked flask equipped with a thermometer and a magnetic stirrer, and then transferred to a water bath, stirred at 60℃ for 120min, filtered, washed with deionized water until the pH of the washing liquid is 7, and dried to obtain the pretreated diamond; Step A3: the pretreated diamond, tungsten powder, chromium powder, sodium chloride and barium chloride are added into a mortar and mixed for 10-20 min, transferred into a crucible, placed in a microwave high-temperature furnace, argon is introduced, heated to 850-950 DEG C at 30 DEG C / min, kept for 0.5-1.5 h, ground for 10-20 min after cooling, ultrasonic for 30-60 min, placed in a drying oven for drying, to obtain chromium-tungsten coated diamond.

[0005] As a further scheme of the present application: the use amount ratio of the diamond and the sodium hydroxide solution in step A1 is 5-10 g: 100-200 mL.

[0006] As a further scheme of the present application: the mass fraction of the sodium hydroxide solution in step A1 is 20%.

[0007] As a further scheme of the present application: the particle size of the diamond in step A1 is 50-70 μm.

[0008] As a further scheme of the present application: the use amount ratio of the alkali washed diamond and the hydrochloric acid solution in step A2 is 5-10 g: 100-200 mL.

[0009] As a further scheme of the present application: the mass fraction of the hydrochloric acid solution in step A2 is 18.5%.

[0010] As a further scheme of the present application: the use amount ratio of the pretreated diamond, tungsten powder, chromium powder, sodium chloride and barium chloride in step A3 is 5-10 g: 15-30 g: 15-30 g: 5-10 g: 5-10 g.

[0011] As a further scheme of the present application: the particle size of the tungsten powder and the chromium powder in step A3 is 1-5 μm.

[0012] As a further scheme of the present application: the aluminum nitride coated copper powder is prepared by the following steps: The copper powder and the aluminum nitride are added into a ball mill, ball-milled at 150 r / min for 16 h to obtain the aluminum nitride coated copper powder.

[0013] As a further scheme of the present application: the use amount ratio of the copper powder and the aluminum nitride is 8.5-17 g: 1.5-3 g.

[0014] As a further scheme of the present application: the particle size of the copper powder is 20 μm.

[0015] As a further scheme of the present application: the particle size of the aluminum nitride is 1-2.5 μm.

[0016] As a further scheme of the present application: the lanthanum-magnesium-titanium-aluminum alloy powder is prepared by the following steps: The magnesium powder, titanium powder, aluminum powder and lanthanum phosphate are added into a powder mixing machine and mixed for 5h, are transferred into a ball milling tank, argon is introduced for protection, the ball-to-material ratio is 60:1, and ball milling is carried out at 400r / min for 2h to obtain the lanthanum-magnesium-titanium-aluminum alloy powder.

[0017] As a further scheme of the present application, the use amount ratio of the magnesium powder, titanium powder, aluminum powder and lanthanum phosphate is 7.2-14.4g:1.4-2.8g:0.7-1.4g:0.7-1.4g.

[0018] As a further scheme of the present application, the particle size of the magnesium powder, titanium powder and aluminum powder is 50-100μm.

[0019] In a second aspect, the present application provides a preparation method of a diamond-copper high-thermal-conductivity composite material, comprising the following steps: Step one: according to weight parts, 30-60 parts of chromium-tungsten coated diamond, 30-60 parts of aluminum nitride coated copper powder and 15-20 parts of lanthanum-magnesium-titanium-aluminum alloy powder are weighed and prepared; Step two: the chromium-tungsten coated diamond, aluminum nitride coated copper powder and lanthanum-magnesium-titanium-aluminum alloy powder are mixed, heated to 900-1050℃ at 50-100℃ / min, vacuum sintered at 20-40MPa for 5-15min, and then cooled to 24-26℃ to obtain the diamond-copper composite material. Beneficial effects

[0020] The diamond-copper high-thermal-conductivity composite material of the present application takes the chromium-tungsten coated diamond and aluminum nitride coated copper powder as the matrix and adds the lanthanum-magnesium-titanium-aluminum alloy powder, so that the whole material can maintain high thermal conductivity in a high-temperature environment, and meanwhile has good mechanical properties and processability.

[0021] In the preparation of the diamond-copper high-thermal-conductivity composite material, the diamond is first subjected to surface treatment to remove impurities and grease etc. attached to the surface of the diamond raw material, and the diamond surface is plated with tungsten and chromium. Chromium and tungsten react with carbon atoms on the surface of the diamond at high temperature to form carbide, forming a chemical bonding interface, enhancing the wettability of the diamond and copper, avoiding interface voids, improving the bonding strength of the diamond and copper matrix and improving the thermal conduction efficiency. The surface of the copper powder is coated with aluminum nitride. Aluminum nitride has high thermal conductivity, and after coating the copper powder, a "copper-aluminum nitride-copper" thermal conduction network is formed, avoiding local heat accumulation. The lanthanum-magnesium-titanium-aluminum alloy refines the grains, forms a thermal stable phase, reduces the overall thermal expansion coefficient of the composite material, reduces thermal cycle fatigue, and lanthanum can promote the uniform nucleation of the carbonized layer on the surface of the diamond. Magnesium and aluminum improve the flowability of the matrix, promote sintering densification, and the lanthanum-magnesium-titanium-aluminum alloy can protect the diamond and copper matrix from oxidation or corrosion, prolonging the service life of the material in harsh environments such as high temperature and high humidity. Specific embodiments

[0022] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application. Embodiment 1

[0023] The embodiment is a preparation method of a diamond-copper high-thermal-conductivity composite material, including the following steps. Step S1: 5 g of diamond, 100 mL of sodium hydroxide solution are added into a three-necked flask provided with a thermometer and a magnetic stirrer, and are transferred into a water bath kettle, stirred at 90 DEG C for 15 min, washed with deionized water until the pH of the washing liquid is 7, filtered, and the alkali-washed diamond is obtained; wherein the particle size of the diamond is 50-70 mu m; Step S2: 5 g of the alkali-washed diamond, 100 mL of hydrochloric acid solution are added into a three-necked flask provided with a thermometer and a magnetic stirrer, and are transferred into a water bath kettle, stirred at 60 DEG C for 120 min, filtered, washed with deionized water until the pH of the washing liquid is 7, and dried to obtain the pretreated diamond; Step S3: 5 g of the pretreated diamond, 15 g of tungsten powder, 15 g of chromium powder, 5 g of sodium chloride and 5 g of barium chloride are added into a mortar and mixed for 10 min, are transferred into a crucible, are placed in a microwave high-temperature furnace, argon is introduced, the temperature is raised to 850 DEG C at a rate of 30 DEG C / min, and is kept for 0.5 h, after cooling, grinding for 10 min, ultrasonic treatment for 30 min, and drying in a drying oven, the chromium-tungsten coated diamond is obtained; wherein the particle size of the tungsten powder and the chromium powder is 1-5 mu m; Step S4: 8.5 g of copper powder, 1.5 g of aluminum nitride are added into a ball mill, ball-milled at 150 r / min for 16 h to obtain the aluminum nitride coated copper powder; wherein the particle size of the copper powder is 20 mu m; the particle size of the aluminum nitride is 1-2.5 mu m; Step S5: 7.2 g of magnesium powder, 1.4 g of titanium powder, 0.7 g of aluminum powder and 0.7 g of lanthanum phosphate are added into a powder mixer and mixed for 5 h, are transferred into a ball mill tank, argon is introduced for protection, the ball-to-material ratio is 60:1, and ball-milling is carried out at 400 r / min for 2 h to obtain lanthanum-magnesium-titanium-aluminum alloy powder; wherein the particle size of the magnesium powder, the titanium powder and the aluminum powder is 50-100 mu m; Step S6: the chromium-tungsten coated diamond 30 parts, the aluminum nitride coated copper powder 30 parts and the lanthanum-magnesium-titanium-aluminum alloy powder 15 parts are weighed according to the weight parts, and are prepared for use; Step S7: mix the chromium-tungsten coated diamond, aluminum nitride coated copper powder and lanthanum-magnesium-titanium-aluminum alloy powder, heat to 900 DEG C at 50 DEG C / min, vacuum sinter at 20 MPa for 5 min, and then cool to 24 DEG C to obtain the diamond-copper composite material. Example 2:

[0024] The embodiment is a preparation method of a diamond-copper high-thermal-conductivity composite material, comprising the following steps: Step S1: add 7.5 g of diamond and 150 mL of sodium hydroxide solution into a three-necked flask provided with a thermometer and a magnetic stirrer, transfer to a water bath, stir at 90 DEG C for 15 min, wash with deionized water until the pH of the washing liquid is 7, filter, and obtain the alkali-washed diamond; wherein the particle size of the diamond is 50-70 mu m; Step S2: add 7.5 g of the alkali-washed diamond and 150 mL of hydrochloric acid solution into a three-necked flask provided with a thermometer and a magnetic stirrer, transfer to a water bath, stir at 60 DEG C for 120 min, filter, wash with deionized water until the pH of the washing liquid is 7, and dry to obtain the pretreated diamond; Step S3: add 7.5 g of the pretreated diamond, 22.5 g of tungsten powder, 22.5 g of chromium powder, 7.5 g of sodium chloride and 7.5 g of barium chloride into a mortar, mix for 15 min, transfer to a crucible, introduce argon into a microwave high-temperature furnace, heat to 800 DEG C at 30 DEG C / min, keep for 1 h, grind for 15 min after cooling, ultrasonic for 45 min, and dry in a drying oven to obtain the chromium-tungsten coated diamond; wherein the particle size of the tungsten powder and the chromium powder is 1-5 mu m; Step S4: add 12.75 g of copper powder and 2.25 g of aluminum nitride into a ball mill, ball mill at 150 r / min for 16 h to obtain the aluminum nitride coated copper powder; wherein the particle size of the copper powder is 20 mu m; and the particle size of the aluminum nitride is 1-2.5 mu m; Step S5: add 10.8 g of magnesium powder, 2.1 g of titanium powder, 10.5 g of aluminum powder and 10.5 g of lanthanum phosphate into a powder mixer, mix for 5 h, transfer to a ball mill tank, introduce argon protection, ball-to-material ratio is 60:1, ball mill at 400 r / min for 2 h to obtain the lanthanum-magnesium-titanium-aluminum alloy powder; wherein the particle size of the magnesium powder, the titanium powder and the aluminum powder is 50-100 mu m; Step S6: weigh chromium-tungsten coated diamond 45 parts, aluminum nitride coated copper powder 45 parts and lanthanum-magnesium-titanium-aluminum alloy powder 17.5 parts according to the weight parts, and reserve; Step S7: mix the chromium-tungsten coated diamond, aluminum nitride coated copper powder and lanthanum-magnesium-titanium-aluminum alloy powder, heat to 1000 DEG C at 75 DEG C / min, vacuum sinter at 30 MPa for 10 min, and then cool to 25 DEG C to obtain the diamond-copper composite material. Example 3

[0025] The embodiment is a preparation method of a diamond-copper high-thermal-conductivity composite material, including the following steps. Step S1: 10g of diamond, 200mL of sodium hydroxide solution are added into a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred into a water bath, stirred at 90℃ for 15min, washed with deionized water until the pH of the washing liquid is 7, filtered, and the alkali-washed diamond is obtained; wherein the particle size of the diamond is 50-70μm; Step S2: 10g of the alkali-washed diamond, 200mL of hydrochloric acid solution are added into a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred into a water bath, stirred at 60℃ for 120min, filtered, washed with deionized water until the pH of the washing liquid is 7, and dried to obtain the pretreated diamond; Step S3: 10g of the pretreated diamond, 30g of tungsten powder, 30g of chromium powder, 10g of sodium chloride, and 10g of barium chloride are added into a mortar and mixed for 20min, transferred into a crucible, placed in a microwave high-temperature furnace, and argon is introduced, heated to 950℃ at a rate of 30℃ / min, and kept for 1.5h, ground for 20min after cooling, ultrasonically treated for 60min, and dried in a drying oven to obtain the chromium-tungsten-coated diamond; wherein the particle size of the tungsten powder and the chromium powder is 1-5μm; Step S4: 17g of copper powder, 3g of aluminum nitride are added into a ball mill, ball-milled at 150r / min for 16h to obtain the aluminum nitride-coated copper powder; wherein the particle size of the copper powder is 20μm; and the particle size of the aluminum nitride is 1-2.5μm; Step S5: 14.4g of magnesium powder, 2.8g of titanium powder, 1.4g of aluminum powder, and 1.4g of lanthanum phosphate are added into a powder mixer and mixed for 5h, transferred into a ball mill tank, argon is introduced for protection, the ball-to-material ratio is 60:1, and ball-milling is performed at 400r / min for 2h to obtain the lanthanum-magnesium-titanium-aluminum alloy powder; wherein the particle size of the magnesium powder, the titanium powder, and the aluminum powder is 50-100μm; Step S6: the chromium-tungsten-coated diamond 60 parts, the aluminum nitride-coated copper powder 60 parts, and the lanthanum-magnesium-titanium-aluminum alloy powder 20 parts are weighed according to the weight parts, and reserved; Step S7: the chromium-tungsten-coated diamond, the aluminum nitride-coated copper powder, and the lanthanum-magnesium-titanium-aluminum alloy powder are mixed, heated to 1050℃ at a rate of 100℃ / min, vacuum sintered at 40MPa for 15min, and then cooled to 26℃ to obtain the diamond-copper composite material.

[0026] Comparative Example 1 The comparative example is a preparation method of a diamond-copper high-thermal-conductivity composite material, including the following steps. Step S1: 10 g of diamond, 200 mL of sodium hydroxide solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 90 DEG C for 15 min, washed with deionized water until the washing liquid pH was 7, filtered, and the alkali washed diamond was obtained; wherein the particle size of the diamond was 50-70 μm; Step S2: 10 g of alkali washed diamond, 200 mL of hydrochloric acid solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 60 DEG C for 120 min, filtered, washed with deionized water until the washing liquid pH was 7, dried, and the pretreated diamond was obtained; Step S3: 17 g of copper powder, 3 g of aluminum nitride were added to a ball mill, ball milled at 150 r / min for 16 h, and the aluminum nitride coated copper powder was obtained; wherein the particle size of the copper powder was 20 μm; the particle size of the aluminum nitride was 1-2.5 μm; Step S4: 14.4 g of magnesium powder, 2.8 g of titanium powder, 1.4 g of aluminum powder, and 1.4 g of lanthanum phosphate were mixed in a powder mixer for 5 h, transferred to a ball mill tank, protected by argon gas, the ball-to-material ratio was 60:1, ball milled at 400 r / min for 2 h, and the lanthanum magnesium titanium aluminum alloy powder was obtained; wherein the particle size of the magnesium powder, titanium powder, and aluminum powder was 50-100 μm; Step S5: The pretreated diamond 60 parts, the aluminum nitride coated copper powder 60 parts, and the lanthanum magnesium titanium aluminum alloy powder 20 parts were weighed according to the weight parts, and reserved; Step S6: The pretreated diamond, the aluminum nitride coated copper powder, and the lanthanum magnesium titanium aluminum alloy powder were mixed, heated to 1050 DEG C at 100 DEG C / min, vacuum sintered at 40 MPa for 15 min, and then cooled to 26 DEG C, and the diamond, copper composite material was obtained.

[0027] Comparative Example 2: The present comparative example is a preparation method of a diamond, copper high thermal conductivity composite material, comprising the following steps: Step S1: 10 g of diamond, 200 mL of sodium hydroxide solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 90 DEG C for 15 min, washed with deionized water until the washing liquid pH was 7, filtered, and the alkali washed diamond was obtained; wherein the particle size of the diamond was 50-70 μm; Step S2: 10 g of alkali washed diamond, 200 mL of hydrochloric acid solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 60 DEG C for 120 min, filtered, washed with deionized water until the washing liquid pH was 7, dried, and the pretreated diamond was obtained; Step S3: 10 g of pretreated diamond, 30 g of tungsten powder, 30 g of chromium powder, 10 g of sodium chloride and 10 g of barium chloride were added to a mortar and mixed for 20 min, transferred to a crucible, placed in a microwave high-temperature furnace, argon was introduced, heated to 950 DEG C at 30 DEG C / min, kept for 1.5 h, ground for 20 min after cooling, ultrasonic for 60 min, dried in a drying oven, to obtain chromium-tungsten coated diamond; wherein the particle size of the tungsten powder and the chromium powder is 1-5 μm; Step S4: 14.4 g of magnesium powder, 2.8 g of titanium powder, 1.4 g of aluminum powder and 1.4 g of lanthanum phosphate were added to a powder mixer and mixed for 5 h, transferred to a ball mill tank, argon was introduced for protection, the ball-to-material ratio was 60:1, ball milling was carried out at 400 r / min for 2 h, to obtain lanthanum-magnesium-titanium-aluminum alloy powder; wherein the particle size of the magnesium powder, the titanium powder and the aluminum powder is 50-100 μm; Step S5: chromium-tungsten coated diamond 60 parts, copper powder 60 parts and lanthanum-magnesium-titanium-aluminum alloy powder 20 parts were weighed according to weight parts, for standby use; wherein the particle size of the copper powder is 20 μm; Step S6: chromium-tungsten coated diamond, copper powder and lanthanum-magnesium-titanium-aluminum alloy powder were mixed, heated to 1050 DEG C at 100 DEG C / min, vacuum sintered at 40 MPa for 15 min, and then cooled to 26 DEG C, to obtain diamond-copper composite material.

[0028] Comparative Example 3: The present comparative example is a preparation method of diamond-copper high-thermal-conductivity composite material, comprising the following steps: Step S1: 10 g of diamond, 200 mL of sodium hydroxide solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 90 DEG C for 15 min, washed with deionized water until the pH of the washing liquid was 7, filtered, to obtain alkali-washed diamond; wherein the particle size of the diamond is 50-70 μm; Step S2: 10 g of alkali-washed diamond, 200 mL of hydrochloric acid solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 60 DEG C for 120 min, filtered, washed with deionized water until the pH of the washing liquid was 7, dried, to obtain pretreated diamond; Step S3: 10 g of pretreated diamond, 30 g of tungsten powder, 30 g of chromium powder, 10 g of sodium chloride and 10 g of barium chloride were added to a mortar and mixed for 20 min, transferred to a crucible, placed in a microwave high-temperature furnace, argon was introduced, heated to 950 DEG C at 30 DEG C / min, kept for 1.5 h, ground for 20 min after cooling, ultrasonic for 60 min, dried in a drying oven, to obtain chromium-tungsten coated diamond; wherein the particle size of the tungsten powder and the chromium powder is 1-5 μm; Step S4: 17g copper powder, 3g aluminum nitride were added into a ball mill, ball milling at 150r / min for 16h to obtain aluminum nitride coated copper powder; wherein the particle size of the copper powder was 20μm; the particle size of the aluminum nitride was 1-2.5μm; Step S5: chromium-tungsten coated diamond 60 parts, aluminum nitride coated copper powder 60 parts were weighed according to weight parts, for standby; Step S6: chromium-tungsten coated diamond, aluminum nitride coated copper powder were mixed, heated to 1050℃ at 100℃ / min, vacuum sintered at 40MPa for 15min, and then cooled to 26℃ to obtain diamond, copper composite material.

[0029] Comparative Example 4: The present comparative example is a preparation method of a diamond, copper high thermal conductivity composite material, comprising the following steps: Step S1: 10g diamond, 200mL sodium hydroxide solution were added into a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred into a water bath, stirred at 90℃ for 15min, washed with deionized water until the washing liquid pH was 7, filtered to obtain alkali washed diamond; wherein the particle size of the diamond was 50-70μm; Step S2: 10g alkali washed diamond, 200mL hydrochloric acid solution were added into a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred into a water bath, stirred at 60℃ for 120min, filtered, washed with deionized water until the washing liquid pH was 7, dried to obtain pretreated diamond; Step S3: 10g pretreated diamond, 30g chromium powder, 10g sodium chloride and 10g barium chloride were added into a mortar and mixed for 20min, transferred into a crucible, placed in a microwave high temperature furnace, argon was introduced, heated to 950℃ at 30℃ / min and kept for 1.5h, ground for 20min after cooling, ultrasonic for 60min, dried in a drying oven to obtain chromium coated diamond; wherein the particle size of the chromium powder was 1-5μm; Step S4: 17g copper powder, 3g aluminum nitride were added into a ball mill, ball milling at 150r / min for 16h to obtain aluminum nitride coated copper powder; wherein the particle size of the copper powder was 20μm; the particle size of the aluminum nitride was 1-2.5μm; Step S5: 14.4g magnesium powder, 2.8g titanium powder, 1.4g aluminum powder and 1.4g lanthanum phosphate were added into a powder mixer and mixed for 5h, transferred into a ball mill tank, argon was introduced for protection, the ball-to-material ratio was 60:1, ball milling at 400r / min for 2h to obtain lanthanum magnesium titanium aluminum alloy powder; wherein the particle size of the magnesium powder, titanium powder and aluminum powder was 50-100μm; Step S6: chromium coated diamond 60 parts, aluminum nitride coated copper powder 60 parts and lanthanum magnesium titanium aluminum alloy powder 20 parts were weighed according to weight parts, for standby; Step S7: mix the tungsten-coated diamond, aluminum nitride-coated copper powder and lanthanum-magnesium-titanium-aluminum alloy powder, heat to 1050 DEG C at 100 DEG C / min, vacuum sinter at 40 MPa for 15 min, and then cool to 26 DEG C to obtain a diamond-copper composite material.

[0030] Comparative Example 5 The present comparative example is a method for preparing a diamond-copper high-thermal-conductivity composite material, comprising the following steps: Step S1: add 10 g of diamond and 200 mL of sodium hydroxide solution to a three-necked flask equipped with a thermometer and a magnetic stirrer, transfer to a water bath, stir at 90 DEG C for 15 min, wash with deionized water until the pH of the washing liquid is 7, filter, and obtain alkali-washed diamond; wherein the particle size of the diamond is 50-70 μm; Step S2: add 10 g of alkali-washed diamond and 200 mL of hydrochloric acid solution to a three-necked flask equipped with a thermometer and a magnetic stirrer, transfer to a water bath, stir at 60 DEG C for 120 min, filter, wash with deionized water until the pH of the washing liquid is 7, and dry to obtain pretreated diamond; Step S3: add 10 g of pretreated diamond, 30 g of tungsten powder, 10 g of sodium chloride and 10 g of barium chloride to a mortar, mix for 20 min, transfer to a crucible, introduce argon into a microwave high-temperature furnace, heat to 950 DEG C at 30 DEG C / min, keep for 1.5 h, grind for 20 min after cooling, ultrasonic for 60 min, and dry in a drying oven to obtain tungsten-coated diamond; wherein the particle size of the tungsten powder is 1-5 μm; Step S4: add 17 g of copper powder and 3 g of aluminum nitride to a ball mill, ball mill at 150 r / min for 16 h to obtain aluminum nitride-coated copper powder; wherein the particle size of the copper powder is 20 μm; and the particle size of the aluminum nitride is 1-2.5 μm; Step S5: add 14.4 g of magnesium powder, 2.8 g of titanium powder, 1.4 g of aluminum powder and 1.4 g of lanthanum phosphate to a powder mixer, mix for 5 h, transfer to a ball mill tank, introduce argon protection, ball-to-material ratio is 60:1, ball mill at 400 r / min for 2 h to obtain lanthanum-magnesium-titanium-aluminum alloy powder; wherein the particle size of the magnesium powder, titanium powder and aluminum powder is 50-100 μm; Step S6: weigh 60 parts of tungsten-coated diamond, 60 parts of aluminum nitride-coated copper powder and 20 parts of lanthanum-magnesium-titanium-aluminum alloy powder according to the weight fraction, and reserve; Step S7: mix the tungsten-coated diamond, aluminum nitride-coated copper powder and lanthanum-magnesium-titanium-aluminum alloy powder, heat to 1050 DEG C at 100 DEG C / min, vacuum sinter at 40 MPa for 15 min, and then cool to 26 DEG C to obtain a diamond-copper composite material.

[0031] Comparative Example 6 The present comparative example is a preparation method of a diamond-copper high-thermal-conductivity composite material, comprising the following steps: Step S1: 10 g of diamond, 200 mL of sodium hydroxide solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 90°C for 15 min, washed with deionized water until the pH of the washing liquid was 7, filtered, and the alkali-washed diamond was obtained; wherein the particle size of the diamond was 50-70 μm; Step S2: 10 g of alkali-washed diamond, 200 mL of hydrochloric acid solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 60°C for 120 min, filtered, washed with deionized water until the pH of the washing liquid was 7, dried, and the pretreated diamond was obtained; Step S3: 14.4 g of magnesium powder, 2.8 g of titanium powder, 1.4 g of aluminum powder, and 1.4 g of lanthanum phosphate were added to a powder mixer and mixed for 5 h, transferred to a ball milling tank, argon was introduced for protection, the ball-to-material ratio was 60:1, and ball milling was performed at 400 r / min for 2 h to obtain lanthanum-magnesium-titanium-aluminum alloy powder; wherein the particle size of the magnesium powder, titanium powder, and aluminum powder was 50-100 μm; Step S4: 60 parts of pretreated diamond, 60 parts of copper powder, and 20 parts of lanthanum-magnesium-titanium-aluminum alloy powder were weighed according to the weight fraction and reserved; wherein the particle size of the copper powder was 20 μm; Step S5: The pretreated diamond, copper powder, and lanthanum-magnesium-titanium-aluminum alloy powder were mixed, heated to 1050°C at 100°C / min, vacuum sintered at 40 MPa for 15 min, and then cooled to 26°C to obtain a diamond-copper composite material.

[0032] Comparative Example 7 The present comparative example is a preparation method of a diamond-copper high-thermal-conductivity composite material, comprising the following steps: Step S1: 10 g of diamond, 200 mL of sodium hydroxide solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 90°C for 15 min, washed with deionized water until the pH of the washing liquid was 7, filtered, and the alkali-washed diamond was obtained; wherein the particle size of the diamond was 50-70 μm; Step S2: 10 g of alkali-washed diamond, 200 mL of hydrochloric acid solution were added to a three-necked flask equipped with a thermometer and a magnetic stirrer, transferred to a water bath, stirred at 60°C for 120 min, filtered, washed with deionized water until the pH of the washing liquid was 7, dried, and the pretreated diamond was obtained; Step S3: 10 g of pretreated diamond, 30 g of tungsten powder, 30 g of chromium powder, 10 g of sodium chloride and 10 g of barium chloride were added into a mortar and mixed for 20 min, transferred into a crucible, placed in a microwave high-temperature furnace, argon was introduced, heated to 950℃ at a rate of 30℃ / min and kept for 1.5 h, ground for 20 min after cooling, ultrasonic for 60 min, dried in a drying oven, to obtain chromium-tungsten coated diamond; wherein the particle size of the tungsten powder and the chromium powder is 1-5 μm; Step S4: 17 g of copper powder and 3 g of aluminum nitride were added into a ball mill and ball milled at 150 r / min for 16 h to obtain aluminum nitride coated copper powder; wherein the particle size of the copper powder is 20 μm; the particle size of the aluminum nitride is 1-2.5 μm; Step S5: 14.4 g of magnesium powder, 2.8 g of titanium powder and 1.4 g of aluminum powder were added into a powder mixer and mixed for 5 h, transferred into a ball mill tank, argon was introduced for protection, the ball-to-material ratio was 60:1, ball milled at 400 r / min for 2 h to obtain magnesium-titanium-aluminum alloy powder; wherein the particle size of the magnesium powder, titanium powder and aluminum powder is 50-100 μm; Step S6: chromium-tungsten coated diamond 60 parts, aluminum nitride coated copper powder 60 parts and magnesium-titanium-aluminum alloy powder 20 parts were weighed according to the weight parts and prepared for use; Step S7: the chromium-tungsten coated diamond, aluminum nitride coated copper powder and magnesium-titanium-aluminum alloy powder were mixed, heated to 1050℃ at a rate of 100℃ / min, vacuum sintered at 40 MPa for 15 min, and then cooled to 26℃ to obtain a diamond-copper composite material.

[0033] Performance test The actual density of the composite materials of Examples 1-3 and Comparative Examples 1-7 was measured by Archimedes drainage method, the composite materials were polished and soaked in anhydrous ethanol solution in an ultrasonic oscillator at 100 Hz for 10 min, dried, and the mass of the composite materials in air and distilled water was measured respectively to calculate the actual density, the theoretical density of the composite material was calculated, and the density was obtained by dividing the measured actual volume density of the composite material by the calculated theoretical density; the thermal diffusivity and specific heat capacity of the composite material were tested by a laser thermal conductivity instrument, and the thermal conductivity of the composite material was calculated.

[0034]

[0035] Referring to the table, according to the comparison between Examples 1-3 and Comparative Examples 1-7, it can be seen that the composite material prepared by taking chromium-tungsten coated diamond and aluminum nitride coated copper powder as the matrix and adding lanthanum-magnesium-titanium-aluminum alloy powder has excellent density and thermal conductivity; According to the comparison between the embodiment 3 and the comparative example 1, it can be known that the thermal conductivity of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder is greater than that of the composite material prepared by taking the pretreated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder, which indicates that the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder has higher heat conduction capacity. According to the comparison between the embodiment 3 and the comparative example 2, it can be known that the thermal conductivity of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder is greater than that of the composite material prepared by taking the chromium-tungsten coated diamond and the copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder, which indicates that the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder has higher heat conduction capacity. According to the comparison between the embodiment 3 and the comparative example 3, it can be known that the thermal conductivity of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder is greater than that of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix, which indicates that the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder has higher heat conduction capacity. According to the comparison between the embodiment 3 and the comparative example 4, it can be known that the thermal conductivity of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder is greater than that of the composite material prepared by taking the chromium coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder, which indicates that the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder has higher heat conduction capacity. According to the comparison between the embodiment 3 and the comparative example 5, it can be known that the thermal conductivity of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder is greater than that of the composite material prepared by taking the tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder, which indicates that the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder has higher heat conduction capacity. According to the comparison between the embodiment 3 and the comparative example 6, it can be known that the thermal conductivity of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder is greater than that of the composite material prepared by taking the pretreated diamond and the copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder, which indicates that the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder has higher heat conduction capacity. According to the comparison between the embodiment 3 and the comparative example 7, it can be seen that the thermal conductivity of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder is greater than that of the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the magnesium-titanium-aluminum alloy powder, which indicates that the composite material prepared by taking the chromium-tungsten coated diamond and the aluminum nitride coated copper powder as the matrix and adding the lanthanum-magnesium-titanium-aluminum alloy powder has higher heat conduction capacity.

[0036] In the description of the present specification, the description referring to the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0037] The above is only an example and description of the present application, and those skilled in the art can make various modifications or supplements or use similar ways to replace the described specific embodiments, as long as they do not deviate from the invention or exceed the scope defined in the present application, which shall belong to the protection scope of the present application.

Claims

1. A diamond, copper high thermal conductivity composite material, characterized by, The following components by weight parts are included: 30-60 parts of chromium-tungsten coated diamond, 30-60 parts of aluminum nitride coated copper powder, and 15-20 parts of lanthanum-magnesium-titanium-aluminum alloy powder; The chromium-tungsten coated diamond is prepared by the following steps: Step A1: diamond, sodium hydroxide solution are added to a flask, transferred to a water bath pot for stirring, washed with deionized water, filtered, and the alkali washed diamond is obtained; Step A2: the alkali washed diamond, hydrochloric acid solution are added to a flask, transferred to a water bath pot for stirring, filtered, washed with deionized water, and dried to obtain pretreated diamond; Step A3: the pretreated diamond, tungsten powder, chromium powder, sodium chloride and barium chloride are mixed in a mortar, transferred to a crucible, argon is introduced, heated and kept, cooled and ground, ultrasonic, and dried in a drying oven to obtain chromium-tungsten coated diamond.

2. The diamond, copper high thermal conductivity composite material of claim 1, wherein, The amount ratio of the diamond and the sodium hydroxide solution in step A1 is 5-10g:100-200mL; the mass fraction of the sodium hydroxide solution is 20%; and the particle size of the diamond is 50-70μm.

3. The diamond, copper high thermal conductivity composite material of claim 1, wherein, The amount ratio of the alkali washed diamond and the hydrochloric acid solution in step A2 is 5-10g:100-200mL; and the mass fraction of the hydrochloric acid solution is 18.5%.

4. The diamond, copper high thermal conductivity composite material of claim 1, wherein, The amount ratio of the pretreated diamond, tungsten powder, chromium powder, sodium chloride and barium chloride in step A3 is 5-10g:15-30g:15-30g:5-10g:5-10g; and the particle size of the tungsten powder and the chromium powder is 1-5μm.

5. The diamond, copper high thermal conductivity composite material of claim 1, wherein, The aluminum nitride coated copper powder is prepared by the following steps: Copper powder and aluminum nitride are ball milled in a ball mill to obtain aluminum nitride coated copper powder.

6. The diamond, copper high thermal conductivity composite material of claim 5, wherein, The amount ratio of the copper powder and the aluminum nitride is 8.5-17g:1.5-3g; the particle size of the copper powder is 20μm; and the particle size of the aluminum nitride is 1-2.5μm.

7. The diamond, copper high thermal conductivity composite material of claim 1, wherein, The lanthanum-magnesium-titanium-aluminum alloy powder is prepared by the following steps: Magnesium powder, titanium powder, aluminum powder and lanthanum phosphate are mixed in a powder mixer, transferred to a ball mill tank, and argon is introduced for protection; the ball-to-material ratio is 60:1, and ball milling is performed to obtain lanthanum-magnesium-titanium-aluminum alloy powder; The amount ratio of the magnesium powder, titanium powder, aluminum powder and lanthanum phosphate is 7.2-14.4g:1.4-2.8g:0.7-1.4g:0.7-1.4g; and the particle size of the magnesium powder, titanium powder and aluminum powder is 50-100μm.

8. A method of producing the diamond-copper high thermal conductivity composite material according to any one of claims 1 to 7, characterized by, The following steps are included: Step one: chromium-tungsten coated diamond 30-60 parts, aluminum nitride coated copper powder 30-60 parts, and lanthanum-magnesium-titanium-aluminum alloy powder 15-20 parts are weighed according to weight parts, and prepared for use; Step two: chromium-tungsten coated diamond, aluminum nitride coated copper powder and lanthanum-magnesium-titanium-aluminum alloy powder are mixed, heated to 900-1050℃ at a rate of 50-100℃ / min, vacuum sintered at 20-40MPa for 5-15min, and then cooled to 24-26℃ to obtain diamond-copper composite material.

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