Preparation method of titanium aluminum carbide reinforced tungsten copper alloy

Abstract

The invention discloses a preparation method of a titanium aluminum carbide reinforced tungsten copper alloy, which comprises the following steps of: plating copper on the surface of a raw material to improve the interface wettability among tungsten powder, titanium aluminum carbide and copper powder, and adding rare earth elements to improve the strength; a two-step oscillation pressure sintering process is adopted to improve the sinterability of the titanium aluminum carbide enhanced tungsten copper alloy, eliminate internal cavities of the material and realize a uniform and compact organization structure; and the titanium aluminum carbide and the rare earth elements can be more uniformly dispersed in an alloy matrix through mechanical alloying, so that the mechanical property and the electrical property of the composite material are improved. The titanium aluminum carbide reinforced wear-resistant tungsten copper alloy with high strength and high conductivity prepared by the method disclosed by the invention can be well suitable for an electrical contact material and an electronic packaging material in a high-capacity and ultrahigh-voltage power transmission network.

Description

Technical Field

[0001] The invention belongs to the technical field of electric contact material preparation methods, and in particular relates to a preparation method of a titanium carbide aluminum reinforced tungsten-copper alloy. Background Art

[0002] Copper and copper alloy materials play an indispensable role in many industrial fields due to their excellent electrical conductivity, thermal conductivity and excellent machinability. However, the shortcomings of traditional copper alloys in strength, hardness and wear resistance limit their use in high-performance application scenarios. Therefore, ensuring high electrical conductivity and improving the strength of copper alloys has become one of the urgent problems to be solved today.

[0003] Tungsten-copper alloy combines the high temperature resistance and high strength of tungsten with the high plasticity and high electrical and thermal conductivity of copper, and is widely used in electrical contact materials. Tungsten-copper electric contact vacuum switches play a very important role in the safe operation of ultra-high voltage power grids. Their working mechanism is to use insulating and arc-extinguishing media to achieve current interruption. The switch frequently connects and disconnects the load current, and the surface is prone to friction and wear, so the tungsten-copper alloy material requires a lower friction coefficient and higher wear resistance. The quality of the contact material directly determines the reliability, safety and service life of the vacuum switch. Therefore, the electrical contact material requires high thermal and electrical conductivity, voltage resistance, large current breaking capacity, low current cutoff value, strong resistance to welding, low arc burn rate and good mechanical properties.

[0004] But the existing technical problems are: 1. Pure copper contacts have good electrical and thermal conductivity, but low current interception level and poor resistance to welding, which affects their service life.

[0005] 2. Pure tungsten contacts have long service life and good breaking capacity, but the breaking current and interception level are too high.

[0006] 3. Tungsten copper alloy has good breaking ability and strong conductivity, but the interface wettability between the alloys is poor, and it is difficult to densify during the sintering process, which affects the microstructure and performance. Summary of the invention

[0007] The purpose of the present invention is to provide a method for preparing a titanium aluminum carbide reinforced tungsten copper alloy, thereby solving the problem of poor compactness of tungsten copper electrical contact materials due to poor interface wettability.

[0008] The technical scheme adopted by the present invention is: a preparation method of titanium carbide aluminum reinforced tungsten copper alloy, which improves the interface wettability between tungsten powder, titanium carbide aluminum and copper powder by copper plating on the surface of raw materials, and then adds rare earth elements to improve the strength; adopts a two-step oscillation pressure sintering process to improve the sinterability of titanium carbide aluminum reinforced tungsten copper alloy, eliminates the internal voids of the material, and realizes its uniform and dense organizational structure; through mechanical alloying, titanium carbide aluminum and rare earth elements can be more evenly dispersed in the alloy matrix, thereby improving the mechanical properties and electrical properties of the composite material.

[0009] The technical solution adopted by the present invention is also characterized in that: Furthermore, the preparation method of titanium aluminum carbide reinforced tungsten copper alloy is specifically prepared according to the following steps: Step 1: Copper plating on the surface of tungsten powder: Use an acid solution to coarsen the tungsten powder to make tiny holes appear on the surface of the tungsten powder. After washing and drying, the coarsened tungsten powder is obtained. The coarsened tungsten powder and copper powder are ball-milled in a certain volume ratio to obtain copper-plated tungsten powder; Step 2: Copper plating on the surface of titanium aluminum carbide: pre-treat titanium aluminum carbide with an alkaline solution, collect the treated powder, wash and dry to obtain titanium aluminum carbide powder, and ball-mill the titanium aluminum carbide powder and copper powder according to a certain volume ratio to obtain copper-coated titanium aluminum carbide powder; Step 3: Mechanical ball milling: The copper-plated tungsten powder, copper-plated titanium aluminum carbide powder, copper powder and rare earth yttrium in step 1 are mixed and ball milled to obtain a tungsten-copper mixed powder; Step 4: Pressing and molding: Press the composite powder obtained in step 3 tightly to obtain a tungsten-copper alloy blank; Step 5: Two-step oscillation pressure sintering: A two-step sintering method is used. In the first step, the tungsten-copper alloy blank obtained in step 4 is oscillated and rapidly pressurized and quickly heated to a higher temperature, and kept warm for a period of time; in the second step, the pressure and temperature are reduced while maintaining the oscillation, and maintained for a long time; finally, the pressure is removed and kept warm for a period of time, and the tungsten-copper composite material can be obtained after cooling with the furnace temperature; Furthermore, step 1 is as follows: Step 1.1 Roughening treatment: Use a hydrogen ion concentration of 10 -5 mol / L~10 -2 mol / L HCl solution to coarsen the tungsten powder, so that tiny holes appear on the surface of the tungsten powder, and then wash the tungsten powder particles with deionized water for 3 to 5 times until neutral, and place them in a vacuum drying oven at 50 to 80°C for 5 to 10 hours to obtain coarsened tungsten powder; Step 1.2 Mechanical alloying: Pour the roughened tungsten powder and copper powder into a stainless steel ball mill according to a volume ratio of 1:1 to 3:1, then add stainless steel grinding balls according to a ball-to-material ratio of 5:1 to 20:1, and finally fix them on a ball mill for high-energy ball milling at a ball milling speed of 200 to 400 rpm and a vacuum ball milling time of 5 to 14 hours to obtain copper-plated tungsten powder; Furthermore, step 2 is as follows: Step 2.1 pretreatment: adding titanium aluminum carbide to an alkaline solution and ultrasonically stirring for a certain period of time, then washing the collected powder with deionized water until it is neutral, and drying it in a vacuum drying oven to obtain titanium aluminum carbide powder; Step 2.2 Mechanical alloying: Pour titanium aluminum carbide powder and copper powder into a stainless steel ball mill according to a certain volume ratio, then add stainless steel grinding balls according to a certain ball-to-material ratio, and finally fix them on a ball mill for high-energy ball milling to obtain copper-coated titanium aluminum carbide powder.

[0010] Furthermore, in step 2.1, titanium aluminum carbide is added to a pretreatment solution having a hydroxide ion concentration of 10 -4 mol / L~10 -1 mol / L alkaline solution with ultrasonic stirring for 0.5h~2h, then wash with deionized water 3~5 times until neutral, collect the powder and place it in a drying oven, and dry it at 50~80℃ for 5~10h; Step 2.2 The volume ratio of the coarsened titanium aluminum carbide powder to the copper powder in mechanical alloying is 1:1 to 3:1, and the density of titanium aluminum carbide is 4.25 g / cm 3 , copper powder density is 8.96 g / cm 3 , ball-to-material ratio 5:1-15:1, ball milling speed 200-300rpm, vacuum ball milling time 4-10h, finally obtaining copper-plated titanium aluminum carbide powder; Furthermore, step 3 is as follows: Copper-coated tungsten powder, copper-coated titanium carbide aluminum powder, copper powder and rare earth yttrium are placed in a high-energy ball mill together with hard balls, and then the high-energy ball mill is placed in a planetary ball mill to obtain tungsten-copper mixed powder.

[0011] Further, in step 3, the total volume ratios of the copper-coated tungsten powder, copper powder, copper-coated titanium aluminum carbide powder, and rare earth element yttrium to the four powders are 70% to 85%, 5% to 10%, 6% to 10%, and 4% to 10%, respectively, the hard ball is a tungsten carbide ball, the ball-to-material ratio is 2:1 to 5:1, the ball milling speed is 200 to 300 r / min, and the ball milling time is 1 to 5 hours, and finally a composite powder is obtained; Furthermore, step 4 is as follows: the composite powder obtained in step 3 is loaded into a mold, placed in a cold isostatic press and compacted, and finally a tungsten-copper alloy blank is obtained; the pressing pressure is 150-300 MPa, and the holding time is 200-350 s.

[0012] Furthermore, step 5 is as follows: in the first step, the temperature is quickly raised to 1000-1300°C, the holding time is 1-3h, the oscillation frequency is 1-5Hz, the median oscillation pressure applied during the holding period is 10-30MPa, the amplitude is 1-5MPa, the heating rate is 5-20°C / min, and the pressure increase rate is 1-10MPa / min; in the second step, the temperature is reduced to 900-1100°C, the holding time is 3-6h, the oscillation pressure is 10-15MPa, and the amplitude is 1-5MPa. Finally, the holding temperature is between 900-1100°C, the pressure is removed and the holding time is 1-2h, and then the tungsten copper alloy is taken out after cooling with the furnace temperature.

[0013] The beneficial effects of the present invention are: The invention provides a preparation method of titanium carbide aluminum reinforced tungsten copper alloy, which improves the interface wettability between tungsten powder, titanium carbide aluminum and copper powder by copper plating on the surface of raw materials, and then adds rare earth elements to improve the strength; adopts a two-step oscillation pressure sintering process to improve the sinterability of titanium carbide aluminum reinforced tungsten copper alloy, eliminates the internal voids of the material, and realizes its uniform and dense organizational structure; through mechanical alloying, titanium carbide aluminum and rare earth elements can be more evenly dispersed in the alloy matrix, thereby improving the mechanical properties and electrical properties of the composite material.

[0014] The preparation method of the present invention is through mechanical alloying and oscillating pressure sintering to prepare the titanium carbide aluminum reinforced wear-resistant tungsten copper alloy with high strength and high conductivity, which can be well applied to electrical contact materials and electronic packaging materials in large-capacity and ultra-high voltage transmission networks.

[0015] The preparation method of the present invention increases the interface wettability and fills the cracks on the surface of the material by introducing copper-plated titanium aluminum carbide and rare earth element yttrium at high temperature, strengthens the weldability between particle layers, and further improves the mechanical properties of the material. The two-step pressure oscillation sintering can effectively avoid cracking caused by excessive temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The schematic diagram is a principle diagram of the preparation method of the titanium aluminum carbide reinforced tungsten copper alloy of the present invention; Figure 2 The present invention is a flow chart of the preparation method of the titanium aluminum carbide reinforced tungsten copper alloy; Figure 3a This is the metallographic diagram of tungsten copper material without adding reinforcement phase; Figure 3b It is the metallographic diagram of tungsten copper material with added reinforcement phase. DETAILED DESCRIPTION

[0017] The present invention will be further described below through the accompanying drawings and specific embodiments.

[0018] The present invention provides a method for preparing a titanium aluminum carbide reinforced tungsten copper alloy, wherein the alloy material is prepared by a sintering-infiltration technique, and the steps include: Step 1, copper plating on the surface of tungsten powder: Step 1.1 Roughening treatment: Use an acid solution to roughen the tungsten powder, then wash the tungsten powder particles with deionized water to neutrality, and place them in a vacuum drying oven to dry, thereby obtaining roughened tungsten powder; The roughening process in step 1.1 uses a hydrogen ion concentration of 10 -5 mol / L~10 -2 10g~30g tungsten powder is coarsened with 1 mol / L HCl solution for 2h~20h to make tiny holes appear on the surface of the tungsten powder, and then washed with deionized water for 3~5 times until neutral, and the powder is collected and placed in a drying oven at 50~80℃ for 5~10h to facilitate the subsequent mechanical copper plating; Step 1.2 Mechanical alloying: Pour the roughened tungsten powder and copper powder into a stainless steel ball mill according to a certain volume ratio, then add stainless steel grinding balls according to a certain ball-to-material ratio, and finally fix them on a ball mill for high-energy ball milling to obtain copper-coated tungsten powder; Step 1.2 During the mechanical alloying process, the volume ratio of the coarsened tungsten powder to the copper powder is 1:1 to 3:1 (the density of the tungsten powder is 19.3 g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio 5:1-20:1, ball milling speed 200-400rpm, vacuum ball milling time 5-14h, and finally copper-plated tungsten powder is obtained; Step 2, copper plating on the surface of titanium aluminum carbide: Step 2.1 pretreatment: adding titanium aluminum carbide to an alkaline solution and ultrasonically stirring for a certain period of time, then washing the collected powder with deionized water until it is neutral, and drying it in a vacuum drying oven to obtain titanium aluminum carbide powder; the alkaline solution is a NaOH or KOH solution; Step 2.1 Pretreatment: 5 g to 15 g of titanium aluminum carbide is added to a 10% hydroxide ion concentration -4 mol / L~10 - 1 mol / L NaOH or KOH solution with ultrasonic stirring for 0.5h~2h, then wash with deionized water 3~5 times until neutral, collect the powder and place it in a drying oven, and dry it at 50~80℃ for 5~10h; Step 2.2 Mechanical alloying: Pour titanium aluminum carbide powder and copper powder into a stainless steel ball mill according to a certain volume ratio, then add stainless steel grinding balls according to a certain ball-to-material ratio, and finally fix them on a ball mill for high-energy ball milling to obtain copper-coated titanium aluminum carbide powder; Step 2.2 Mechanical alloying, coarsening the volume ratio of titanium aluminum carbide powder to copper powder is 1:1 to 3:1 (the density of titanium aluminum carbide is 4.25g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio of 5:1-15:1, ball milling speed of 200-300rpm, vacuum ball milling time of 4-10h, and finally obtaining copper-plated titanium aluminum carbide powder; Step 3, mechanical ball milling mixing: Step 3.1: placing copper-coated tungsten powder, copper-coated titanium aluminum carbide powder, copper powder, rare earth yttrium and hard balls into a high-energy ball mill, and then placing the high-energy ball mill into a planetary ball mill to obtain a tungsten-copper mixed powder; Step 3.1: In the ball milling mixing, the total volume ratios of the copper-coated tungsten powder, copper powder, copper-coated titanium aluminum carbide powder, and rare earth element yttrium to the four powders are 70% to 85%, 5% to 10%, 6% to 10%, and 4% to 10%, respectively. The hard ball is a tungsten carbide ball, the ball-to-material ratio is 2:1 to 5:1, the ball milling speed is 200 to 300 r / min, and the ball milling time is 1 to 5 h. Step 4, pressing and molding: The composite powder obtained in step 3 is loaded into a mold, placed in a cold isostatic press and compacted to obtain a tungsten-copper alloy blank; Step 4: using a cold isostatic press to press the blank, the pressing pressure is 150-300 MPa, and the holding time is 200-350 seconds to obtain a tungsten copper alloy blank; Step 5, two-step oscillation pressure sintering: In order to prevent the copper phase from being squeezed out of the composite phase by pressure after the hot pressing sintering temperature exceeds the melting point of copper, the pressed tungsten-copper alloy blank is placed in an oscillating sintering furnace and sintered by a two-step sintering method. First, the tungsten-copper alloy blank obtained in step 4 is rapidly pressurized and quickly heated to a higher temperature, and kept warm for a period of time; then, the pressure is reduced while the temperature is reduced and maintained for a long time; finally, the pressure is removed and the temperature is kept warm for a period of time, and the tungsten-copper composite material can be obtained after cooling with the furnace temperature; In the two-step oscillation pressure sintering in step 5, the sintering temperature is 1000-1300°C, the holding time is 1-3h, the oscillation frequency is 1-5Hz, the median oscillation pressure applied during the holding period is 10-30MPa, the amplitude is 1-5MPa, the heating rate is 5-20°C / min, and the pressure increase rate is 1-10MPa / min; then, the low temperature is 900-1100°C, the holding time is 3-6h, the oscillation pressure is 10-15MPa, the amplitude is 1-5MPa, and finally, the temperature is between 900-1100°C, the pressure is removed and kept warm for 1-2h, and then cooled with the furnace temperature to obtain a wear-resistant titanium aluminum carbide reinforced tungsten copper alloy.

[0019] The preparation method of the titanium aluminum carbide reinforced tungsten copper alloy and its properties are further described below through specific examples.

[0020] Embodiment 1: This embodiment discloses a method for preparing a titanium aluminum carbide reinforced tungsten copper alloy, comprising the following steps: The roughening process in step 1.1 uses a hydrogen ion concentration of 10 -2 20g of tungsten powder was coarsened with 10 mol / L HCl solution for 10 hours to make tiny holes appear on the surface of the tungsten powder, and then washed with deionized water for 3 times until neutral. The powder was collected and placed in a drying oven at 60°C for 6 hours to facilitate subsequent mechanical copper plating; Step 1.2 During the mechanical alloying process, the volume ratio of the roughened tungsten powder to the copper powder is 3:1 (the density of the tungsten powder is 19.3 g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio of 10:1, ball milling speed of 300rpm, vacuum ball milling time of 5h, and finally copper-plated tungsten powder was obtained; Step 2.1 Pretreatment: 5 g of titanium aluminum carbide was added to a 10% hydroxide ion concentration -1 mol / L NaOH or KOH solution with ultrasonic stirring for 1 h, then washed with deionized water three times until neutral, collected the powder and placed it in a drying oven, and dried at 60 ° C for 6 h; Step 2.2 Mechanical alloying, coarsening the volume ratio of titanium aluminum carbide powder to copper powder is 3:1 (the density of titanium aluminum carbide is 4.25g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio 5:1, ball milling speed 200rpm, vacuum ball milling time 6h, and finally copper-coated titanium aluminum carbide powder was obtained; Step 3.1: In the ball milling mixing, the total volume ratios of the copper-coated tungsten powder, copper powder, copper-coated titanium aluminum carbide powder, and rare earth element yttrium are 85%, 5%, 6%, and 4%, respectively. The hard ball is a tungsten carbide ball, the ball-to-material ratio is 3:1, the ball milling speed is 200 r / min, and the ball milling time is 1 h. Step 4: Use a cold isostatic press to press the blank, the pressing pressure is 200 MPa, and the holding time is 300 s to obtain a tungsten copper alloy blank; In step 5, the two-step oscillation pressure sintering has a sintering temperature of 1250°C, a holding time of 2h, an oscillation frequency of 3Hz, a median oscillation pressure of 20MPa, an amplitude of 3MPa, a heating rate of 10°C / min, and a pressure increase rate of 5MPa / min; then, the low temperature is 1000°C, the holding time is 5h, the oscillation pressure is 10MPa, the amplitude is 3MPa, and finally, the temperature is 1000°C, the pressure is removed and kept warm for 1h, and then cooled with the furnace temperature to obtain a wear-resistant titanium aluminum carbide reinforced tungsten copper alloy.

[0021] Embodiment 2: This embodiment discloses a method for preparing a titanium aluminum carbide reinforced tungsten copper alloy, comprising the following steps: The roughening process in step 1.1 uses a hydrogen ion concentration of 10 -3 20g of tungsten powder was coarsened with 10 mol / L HCl solution for 10 hours to make tiny holes appear on the surface of the tungsten powder, and then washed with deionized water for 4 times until neutral. The powder was collected and placed in a drying oven at 50°C for 5 hours to facilitate subsequent mechanical copper plating; Step 1.2 During the mechanical alloying process, the volume ratio of the coarsened tungsten powder to the copper powder is 1:1 (the density of the tungsten powder is 19.3 g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio 5:1, ball milling speed 200rpm, vacuum ball milling time 8h, and finally copper-plated tungsten powder was obtained; Step 2.1 Pretreatment: 5 g of titanium aluminum carbide was added to a 10% hydroxide ion concentration -2 mol / L NaOH solution with ultrasonic stirring for 0.5 h, then washed with deionized water 4 times until neutral, the collected powder was placed in a drying oven and dried at 50 °C for 5 h; Step 2.2 Mechanical alloying, coarsening the volume ratio of titanium aluminum carbide powder to copper powder is 1:1 (the density of titanium aluminum carbide is 4.25g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio of 10:1, ball milling speed of 300 rpm, vacuum ball milling time of 4 h, and finally copper-coated titanium aluminum carbide powder was obtained; Step 3.1: In the ball milling mixing, the total volume ratios of the copper-coated tungsten powder, copper powder, copper-coated titanium aluminum carbide powder, and rare earth element yttrium are 70%, 10%, 10%, and 10%, respectively. The hard ball is a tungsten carbide ball, the ball-to-material ratio is 2:1, the ball milling speed is 240 r / min, and the ball milling time is 5 h. Step 4: Use a cold isostatic press to press the blank, the pressing pressure is 150 MPa, and the holding time is 200 s to obtain a tungsten copper alloy blank; In the two-step oscillation pressure sintering in step 5, the sintering temperature is 1000°C, the holding time is 1h, the oscillation frequency is 1Hz, the median oscillation pressure applied during the holding period is 10MPa, the amplitude is 1MPa, the heating rate is 5°C / min, and the pressure increase rate is 1MPa / min; then, the low temperature is 900°C, the holding time is 3h, the oscillation pressure is 12MPa, the amplitude is 1MPa, and finally, the temperature is between 900°C, the pressure is removed and kept warm for 2h, and then cooled with the furnace temperature to finally obtain a wear-resistant titanium aluminum carbide reinforced tungsten copper alloy.

[0022] Embodiment 3: This embodiment discloses a method for preparing a titanium aluminum carbide reinforced tungsten copper alloy, comprising the following steps: The roughening process in step 1.1 uses a hydrogen ion concentration of 10 -5 20g of tungsten powder was coarsened with 10 mol / L HCl solution for 10 hours to make tiny holes appear on the surface of the tungsten powder, and then washed with deionized water for 5 times until neutral. The powder was collected and placed in a drying oven and dried at 80°C for 10 hours to facilitate subsequent mechanical copper plating. Step 1.2 During the mechanical alloying process, the volume ratio of the roughened tungsten powder to the copper powder is 2:1 (the density of the tungsten powder is 19.3 g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio 20:1, ball milling speed 400rpm, vacuum ball milling time 14h, and finally copper-plated tungsten powder was obtained; Step 2.1 Pretreatment: 5 g of titanium aluminum carbide was added to a 10% hydroxide ion concentration -3 mol / L solution with ultrasonic stirring for 2 h, then washed with deionized water 5 times until neutral, the collected powder was placed in a drying oven and dried at 80 °C for 10 h; Step 2.2 Mechanical alloying, coarsening the volume ratio of titanium aluminum carbide powder to copper powder is 2:1 (the density of titanium aluminum carbide is 4.25g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio of 15:1, ball milling speed of 240 rpm, vacuum ball milling time of 10 h, and finally copper-coated titanium aluminum carbide powder was obtained; Step 3.1: In the ball milling mixing, the total volume ratios of the copper-coated tungsten powder, copper powder, copper-coated titanium aluminum carbide powder, and rare earth element yttrium are 80%, 8%, 7%, and 5%, respectively. The hard ball is a tungsten carbide ball, the ball-to-material ratio is 5:1, the ball milling speed is 300 r / min, and the ball milling time is 5 h. Step 4: Use a cold isostatic press to press the blank, the pressing pressure is 300 MPa, and the holding time is 350 s to obtain a tungsten-copper alloy blank; In step 5, the two-step oscillation pressure sintering has a sintering temperature of 1300°C, a holding time of 3h, an oscillation frequency of 5Hz, a median oscillation pressure of 30MPa, an amplitude of 5MPa, a heating rate of 20°C / min, and a pressure increase rate of 10MPa / min; then, the low temperature is 1100°C, the holding time is 6h, the oscillation pressure is 15MPa, and the amplitude is 5MPa. Finally, the temperature is between 1100°C, the pressure is removed and the temperature is kept for 1.5h, and then it is cooled with the furnace temperature to obtain a wear-resistant titanium aluminum carbide reinforced tungsten copper alloy.

[0023] Embodiment 4: This embodiment discloses a method for preparing a titanium aluminum carbide reinforced tungsten copper alloy, comprising the following steps: In the roughening treatment in step 1.1, 20g of tungsten powder is roughened for 10h with 500mL of 10-30mL / L HCl solution to make tiny holes appear on the surface of the tungsten powder, and then washed with deionized water for 3 times until neutral, and the powder is collected and placed in a drying oven at 60°C for 6h to facilitate subsequent mechanical copper plating; Step 1.2 During the mechanical alloying process, the volume ratio of the roughened tungsten powder to the copper powder is 3:1 (the density of the tungsten powder is 19.3 g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio of 10:1, ball milling speed of 300rpm, vacuum ball milling time of 5h, and finally copper-plated tungsten powder was obtained; Step 2.1 pretreatment: 5 g of titanium aluminum carbide was added to 500 mL of 30 g / L NaOH solution and ultrasonically stirred for 1 h, then washed with deionized water three times until neutral, and the powder was collected and placed in a drying oven and dried at 60 ° C for 6 h; Step 2.2 Mechanical alloying, coarsening the volume ratio of titanium aluminum carbide powder to copper powder is 3:1 (the density of titanium aluminum carbide is 4.25g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio 5:1, ball milling speed 200rpm, vacuum ball milling time 6h, and finally copper-coated titanium aluminum carbide powder was obtained; Step 3.1: In the ball milling mixing, the total volume ratios of the copper-coated tungsten powder, copper powder, copper-coated titanium aluminum carbide powder, and rare earth element yttrium are 85%, 5%, 7%, and 3%, respectively. The hard ball is a tungsten carbide ball, the ball-to-material ratio is 3:1, the ball milling speed is 200 r / min, and the ball milling time is 3 h. Step 4: Use a cold isostatic press to press the blank, the pressing pressure is 200 MPa, and the holding time is 300 s to obtain a tungsten copper alloy blank; In the two-step oscillation pressure sintering in step 5, the sintering temperature is 1250°C, the holding time is 2h, the oscillation frequency is 3Hz, the median oscillation pressure applied during the holding period is 20MPa, the amplitude is 3MPa, the heating rate is 10°C / min, and the pressure increase rate is 5MPa / min; then, the low temperature is 1000°C, the holding time is 5h, the oscillation pressure is 10MPa, the amplitude is 3MPa, and finally, the temperature is between 1000°C, the pressure is removed and kept warm for 1h, and then cooled with the furnace temperature to finally obtain a wear-resistant titanium aluminum carbide reinforced tungsten copper alloy.

[0024] Embodiment 5: This embodiment discloses a method for preparing a titanium aluminum carbide reinforced tungsten copper alloy, comprising the following steps: In the roughening treatment in step 1.1, 20g of tungsten powder is roughened for 10h with 500mL of 10-30mL / L HCl solution to make tiny holes appear on the surface of the tungsten powder, and then washed with deionized water for 3 times until neutral, and the powder is collected and placed in a drying oven at 60°C for 6h to facilitate subsequent mechanical copper plating; Step 1.2 During the mechanical alloying process, the volume ratio of the roughened tungsten powder to the copper powder is 3:1 (the density of the tungsten powder is 19.3 g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio of 10:1, ball milling speed of 300rpm, vacuum ball milling time of 5h, and finally copper-plated tungsten powder was obtained; Step 2.1 pretreatment: 5 g of titanium aluminum carbide was added to 500 mL of 30 g / L NaOH solution and ultrasonically stirred for 1 h, then washed with deionized water three times until neutral, and the powder was collected and placed in a drying oven and dried at 60 ° C for 6 h; Step 2.2 Mechanical alloying, coarsening the volume ratio of titanium aluminum carbide powder to copper powder is 3:1 (the density of titanium aluminum carbide is 4.25g / cm 3 , copper powder density is 8.96 g / cm 3 ), ball-to-material ratio 5:1, ball milling speed 200rpm, vacuum ball milling time 6h, and finally copper-coated titanium aluminum carbide powder was obtained; Step 3.1: In the ball milling mixing, the total volume ratios of the copper-coated tungsten powder, copper powder, copper-coated titanium aluminum carbide powder, and rare earth element yttrium are 85%, 5%, 8%, and 2%, respectively. The hard ball is a tungsten carbide ball, the ball-to-material ratio is 3:1, the ball milling speed is 200 r / min, and the ball milling time is 3 h. Step 4: Use a cold isostatic press to press the blank, the pressing pressure is 200 MPa, and the holding time is 300 s to obtain a tungsten copper alloy blank; In the two-step oscillation pressure sintering in step 5, the sintering temperature is 1250°C, the holding time is 2h, the oscillation frequency is 3Hz, the median oscillation pressure applied during the holding period is 20MPa, the amplitude is 3MPa, the heating rate is 10°C / min, and the pressure increase rate is 5MPa / min; then, the low temperature is 1000°C, the holding time is 5h, the oscillation pressure is 10MPa, the amplitude is 3MPa, and finally, the temperature is between 1000°C, the pressure is removed and kept warm for 1h, and then cooled with the furnace temperature to finally obtain a wear-resistant titanium aluminum carbide reinforced tungsten copper alloy.

[0025] Comparative Example 1: Titanium carbide aluminum reinforced tungsten copper alloy was prepared according to the preparation method of Example 4. However, during the ball milling and mixing in step 3.1, only copper-plated tungsten powder and copper powder were added, accounting for 85% and 15% respectively, and the other steps remained unchanged.

[0026] Table 1 Properties of titanium aluminum carbide reinforced tungsten copper alloys prepared in Examples 1-5 and Comparative Examples

[0027] As can be seen from Table 1, compared with Comparative Example 1, the hardness, bending strength and electrical conductivity of the titanium aluminum carbide reinforced tungsten copper alloy prepared in Examples 1 to 5 of the present invention are significantly improved, and the friction coefficient and wear rate are significantly reduced. Compared with other groups, the alloy performance of Example 4 is significantly improved.

Claims

1. A method for preparing a titanium aluminum carbide reinforced tungsten copper alloy, characterized in that: The interfacial wettability between tungsten powder, titanium aluminum carbide and copper powder is improved by copper plating on the surface of the raw materials, and rare earth elements are added to improve the strength. A two-step oscillation pressure sintering process is used to improve the sintering of titanium aluminum carbide reinforced tungsten copper alloy, eliminate the internal voids of the material, and achieve a uniform and dense organizational structure. Mechanical alloying can more evenly disperse titanium aluminum carbide and rare earth elements in the alloy matrix, thereby improving the mechanical and electrical properties of the composite material.

2. The method for preparing the titanium aluminum carbide reinforced tungsten copper alloy according to claim 1, characterized in that: Specifically prepared according to the following steps: Step 1: Copper plating on the surface of tungsten powder: Use an acid solution to coarsen the tungsten powder to make tiny holes appear on the surface of the tungsten powder. After washing and drying, the coarsened tungsten powder is obtained. The coarsened tungsten powder and copper powder are ball-milled in a certain volume ratio to obtain copper-plated tungsten powder; Step 2: Copper plating on the surface of titanium aluminum carbide: pre-treat titanium aluminum carbide with an alkaline solution, collect the treated powder, wash and dry to obtain titanium aluminum carbide powder, and ball-mill the titanium aluminum carbide powder and copper powder according to a certain volume ratio to obtain copper-coated titanium aluminum carbide powder; Step 3: Mechanical ball milling: The copper-plated tungsten powder, copper-plated titanium aluminum carbide powder, copper powder and rare earth yttrium in step 1 are mixed and ball milled to obtain a tungsten-copper mixed powder; Step 4: Pressing and molding: Press the composite powder obtained in step 3 tightly to obtain a tungsten-copper alloy blank; Step 5: Two-step oscillation pressure sintering: A two-step sintering method is used. In the first step, the tungsten-copper alloy blank obtained in step 4 is oscillated and rapidly pressurized and quickly heated to a higher temperature, and kept warm for a period of time; in the second step, the pressure and temperature are reduced while maintaining the oscillation, and maintained for a long time; finally, the pressure is removed and the temperature is kept warm for a period of time, and the tungsten-copper composite material can be obtained after cooling with the furnace temperature.

3. The method for preparing the titanium aluminum carbide reinforced tungsten copper alloy according to claim 2, characterized in that: The step 1 is specifically as follows: Step 1.1 Roughening treatment: Use a hydrogen ion concentration of 10 -5 mol / L~10 -2 mol / L HCl solution to coarsen the tungsten powder, so that tiny holes appear on the surface of the tungsten powder, and then wash the tungsten powder particles with deionized water for 3 to 5 times until neutral, and place them in a vacuum drying oven at 50 to 80°C for 5 to 10 hours to obtain coarsened tungsten powder; Step 1.2 Mechanical alloying: Pour the coarsened tungsten powder and copper powder into a stainless steel ball mill at a volume ratio of 1:1 to 3:1, then add stainless steel grinding balls at a ball-to-material ratio of 5:1 to 20:1, and finally fix them on a ball mill for high-energy ball milling at a ball milling speed of 200 to 400 rpm and a vacuum ball milling time of 5 to 14 hours to obtain copper-plated tungsten powder.

4. The method for preparing the titanium aluminum carbide reinforced tungsten copper alloy according to claim 2, characterized in that: The step 2 is specifically as follows: Step 2.1 pretreatment: adding titanium aluminum carbide to an alkaline solution and ultrasonically stirring for a certain period of time, then washing the collected powder with deionized water until it is neutral, and drying it in a vacuum drying oven to obtain titanium aluminum carbide powder; Step 2.2 Mechanical alloying: Pour titanium aluminum carbide powder and copper powder into a stainless steel ball mill according to a certain volume ratio, then add stainless steel grinding balls according to a certain ball-to-material ratio, and finally fix them on a ball mill for high-energy ball milling to obtain copper-coated titanium aluminum carbide powder.

5. The method for preparing the titanium aluminum carbide reinforced tungsten copper alloy according to claim 4, characterized in that: In the step 2.1 pretreatment, titanium aluminum carbide is added to a hydrate having a hydroxide ion concentration of 10 -4 mol / L~10 -1 mol / L alkaline solution with ultrasonic stirring for 0.5h~2h, then wash with deionized water 3~5 times until neutral, collect the powder and place it in a drying oven, and dry it at 50~80℃ for 5~10h; The volume ratio of the coarsened titanium aluminum carbide powder to the copper powder in the mechanical alloying step 2.2 is 1:1 to 3:1, and the density of the titanium aluminum carbide is 4.25 g / cm 3 , copper powder density is 8.96 g / cm 3 , ball-to-material ratio of 5:1-15:1, ball milling speed of 200-300rpm, vacuum ball milling time of 4-10h, and finally copper-plated titanium aluminum carbide powder is obtained.

6. The method for preparing the titanium aluminum carbide reinforced tungsten copper alloy according to claim 4, characterized in that: The step 3 is as follows: Copper-coated tungsten powder, copper-coated titanium carbide aluminum powder, copper powder and rare earth yttrium are placed in a high-energy ball mill together with hard balls, and then the high-energy ball mill is placed in a planetary ball mill to obtain a tungsten-copper mixed powder.

7. The method for preparing the titanium aluminum carbide reinforced tungsten copper alloy according to claim 6, characterized in that: In the step 3, the total volume ratios of the copper-plated tungsten powder, copper powder, copper-plated titanium aluminum carbide powder, and rare earth element yttrium are 70% to 85%, 5% to 10%, 6% to 10%, and 4% to 10%, respectively. The hard ball is a tungsten carbide ball, the ball-to-material ratio is 2:1 to 5:1, the ball milling speed is 200 to 300 r / min, and the ball milling time is 1 to 5 hours, and finally a composite powder is obtained.

8. The method for preparing the titanium aluminum carbide reinforced tungsten copper alloy according to claim 1, characterized in that: The step 4 is specifically as follows: the composite powder obtained in step 3 is loaded into a mold, placed in a cold isostatic press and compacted, and finally a tungsten-copper alloy blank is obtained; the pressing pressure is 150-300 MPa, and the holding time is 200-350 s.

9. The method for preparing the titanium aluminum carbide reinforced tungsten copper alloy according to claim 2, characterized in that: The step 5 is specifically as follows: in the first step, the temperature is quickly raised to 1000-1300°C, the holding time is 1-3h, the oscillation frequency is 1-5Hz, the median oscillation pressure applied during the holding period is 10-30MPa, the amplitude is 1-5MPa, the heating rate is 5-20°C / min, and the pressure increase rate is 1-10MPa / min; in the second step, the temperature is lowered to 900-1100°C, the holding time is 3-6h, the oscillation pressure is 10-15MPa, and the amplitude is 1-5MPa. Finally, the holding temperature is between 900-1100°C, the pressure is removed and the holding time is 1-2h, and then the tungsten copper alloy is taken out after cooling with the furnace temperature.

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