CuW contact component and preparation method thereof

Abstract

The invention discloses a CuW contact component and a preparation method thereof, and belongs to the technical field of contact manufacturing, by adding rare earth elements and nano TiC into alloy mixed powder, the wettability of CuW can be improved, W grains are refined, a Cu phase is uniformly filled along a W framework, local aggregation or segregation is avoided, metallurgical bonding is promoted, and the interface strength and stripping resistance of a contact are improved. The problems that a traditional copper-tungsten alloy material is uneven in copper phase distribution, weak in interface bonding, insufficient in density, high in porosity and the like are solved. Besides, in the preparation process, the rare earth oxide can improve the high-temperature stability of a Cu phase, TiC enhances the aggregation effect of a W framework, flowing and evaporation of a Cu liquid phase are reduced, and uniform distribution of the Cu phase also avoids the problem of splashing aggravation caused by local copper enrichment; the problems that in the prior art, a CuW alloy material is prone to corrosion pits, cracks, copper phase evaporation, splashing, contact resistance drifting and the like in the long-term use process are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of contact manufacturing, in particular to a CuW contact component and a preparation method thereof. BACKGROUND

[0002] Copper tungsten alloy (CuW) is widely used in high-voltage circuit breakers, disconnectors and other core components of power systems as contact materials due to its unique physical properties. With the popularization of emerging scenarios such as ultra-high voltage power transmission, large-capacity short-circuit breaking, and new energy grid connection, the performance requirements of electrical contact materials are continuously improving.

[0003] However, traditional copper tungsten alloy materials have problems such as uneven distribution of copper phase, weak interface bonding, insufficient density, and high porosity. In addition, during long-term use, problems such as etch pits, cracks, copper phase evaporation, spattering, and contact resistance drift are prone to occur, resulting in decreased breaking capacity, shortened service life, and frequent failures. SUMMARY

[0004] The main purpose of the present application is to provide a CuW contact component and a preparation method thereof, which aims to solve the problems of uneven distribution of copper phase, weak interface bonding, insufficient density, and high porosity of traditional copper tungsten alloy materials, as well as problems such as etch pits, cracks, copper phase evaporation, spattering, and contact resistance drift that are prone to occur during long-term use.

[0005] To achieve the above purpose, the present application provides a preparation method of a CuW contact component, which comprises: obtaining an alloy mixed powder under predetermined conditions; pressing and forming the alloy mixed powder to obtain a CuW contact component skeleton; sequentially performing vacuum sintering treatment and pressure infiltration treatment on the CuW contact component skeleton to obtain a CuW contact component blank; performing annealing treatment on the CuW contact component blank to obtain the CuW contact component; wherein the alloy mixed powder comprises Cu powder, W powder, La2O3 powder, CeO2 powder, and nano-TiC powder.

[0006] Optionally, the predetermined conditions include: under an inert gas atmosphere, heating to a first temperature and performing first heat preservation; then under a hydrogen atmosphere, heating to a second temperature and performing second heat preservation.

[0007] Optionally, the first temperature is 350℃~420℃, and the duration of the first heat preservation is 2.0h~3.0h; the second temperature is 550℃~620℃, and the duration of the second heat preservation is 2.0h~2.5h.

[0008] Optionally, the mass ratio of Cu powder, W powder and La2O3 powder included in the alloy mixed powder is 30~50:70~85:0.1~1; the amount of CeO2 powder and nano TiC powder added is 0.05%~0.3% and 0.2%~0.6% of the total mass of Cu powder, W powder and La2O3 powder, respectively.

[0009] Optionally, the compression molding includes: The alloy mixture powder was pressurized at 300MPa~400MPa for 25s~30s to obtain a preliminary CuW contact component skeleton; The pre-formed CuW contact component skeleton is placed into a single-cavity hot press mold under a vacuum degree ≥10. -3 Under an environment of Pa, a unidirectional pressure of 600MPa~700MPa is applied, and the surface heating zone temperature of the single-cavity hot press mold is adjusted to 550℃~600℃, and the core heating zone temperature is adjusted to 300℃~350℃. Then, the temperature is maintained for 2.0min~3.0min. After the temperature maintenance is completed, the temperature is allowed to cool naturally to room temperature.

[0010] Optionally, the vacuum sintering process includes: In a vacuum environment, the temperature is raised to the first sintering temperature at the first rate, and a first sintering holding is performed. Nitrogen gas is introduced 25 to 30 minutes at the end of the first sintering holding. Then, the temperature is lowered to the second sintering temperature at the second rate, and a second sintering holding is performed. After completion, the temperature is allowed to cool naturally to room temperature.

[0011] Optionally, the first sintering rate is 3℃ / min~5℃ / min, the first sintering temperature is 1300℃~1500℃, and the duration of the first sintering holding is 2.0h~4.0h; the second sintering rate is 5℃ / min~10℃ / min, and the second sintering temperature is 650℃~750℃.

[0012] Optionally, the pressure infiltration treatment includes: Hydrogen gas is introduced at a rate of 5 L / min to 10 L / min, and the temperature is maintained at 400℃ to 600℃ for 2.0h to 4.0h under a hydrogen atmosphere. After completion, the equipment pressure is adjusted to 1.0GPa to 1.5GPa, and the temperature is simultaneously raised to 950℃ to 1150℃ and maintained for 1.0h to 2.0h, and then naturally cooled to room temperature.

[0013] Optionally, the annealing process includes: Under an inert atmosphere, the temperature is set to 400℃~600℃ and held for 2.0h~4.0h, then allowed to cool naturally to room temperature.

[0014] To achieve the above objectives, the present invention also provides a CuW contact material, which is prepared by the above-described preparation method.

[0015] Compared with the prior art, the beneficial effects that the present invention can achieve are as follows: 1. In the technical solution of this invention, the La2O3 powder and CeO2 powder in the alloy mixed powder can improve the wettability of CuW alloy, while the nano-TiC powder can refine the W grains, so that the Cu phase is uniformly filled along the W skeleton, avoiding local aggregation or segregation; secondly, the La2O3 powder and CeO2 powder can purify the interface and reduce the interface energy, and the nano-TiC is dispersed at the interface and can form an interface transition phase to promote metallurgical bonding and improve the interface shear strength and anti-peeling ability; in addition, the CuW contact component skeleton after pressing can form a continuous W skeleton in the subsequent vacuum sintering process. During the pressure melting process, the Cu liquid can fill the pores of the skeleton. Finally, the annealing treatment eliminates the minor defects of the skeleton, which can increase the density of the component to more than 98.5% relative density and significantly reduce the porosity; thus solving the problems of uneven copper phase distribution, weak interface bonding, insufficient density and high porosity of copper-tungsten alloy components obtained in the prior art.

[0016] 2. In the CuW contact component obtained by this invention, nano-TiC and rare earth oxides have a synergistic strengthening effect, thereby improving the high-temperature hardness and deformation resistance of the CuW alloy material. The subsequent annealing treatment eliminates residual stress and reduces the phenomenon of cracking in the CuW contact component under thermal cycling. Moreover, the copper phase is uniformly distributed, reducing the local overheating concentration caused by arc ablation in the component structure. Secondly, rare earth oxides can improve the high-temperature stability of the Cu phase, and TiC can enhance the aggregation effect of the W skeleton to reduce the flow and evaporation of the Cu liquid phase. The uniform Cu phase distribution avoids the problem of increased splashing caused by local copper enrichment. Finally, it solves the problems of pitting, cracking, copper phase evaporation, splashing, and contact resistance drift that easily occur in CuW alloy materials during long-term use in the prior art. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the process for preparing CuW contact components according to the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] To address the problems of uneven copper phase distribution, weak interfacial bonding, insufficient density, and high porosity in existing tungsten alloy materials, as well as the susceptibility to pitting, cracking, copper phase evaporation, splashing, and contact resistance drift during long-term use, this invention provides a method for preparing CuW contact components, such as... Figure 1 As shown, it includes: S10, alloy mixed powder was prepared under preset conditions; S20, the alloy mixture powder is pressed and molded to obtain a CuW contact component skeleton; S30, the CuW contact component skeleton is subjected to vacuum sintering and pressure melting treatment in sequence to obtain CuW contact component blank; S40, the CuW contact component blank is annealed to obtain the CuW contact component; The alloy mixed powder includes Cu powder, W powder, La2O3 powder, CeO2 powder, and nano TiC powder.

[0020] Optionally, before preparing the alloy mixed powder under the above-mentioned preset conditions, Cu powder with a purity of not less than 99.95%, tungsten powder (W powder) with a purity of not less than 99.99%, and lanthanum oxide (La2O3) powder with a purity of not less than 99.9% can be selected first. The Cu powder, W powder, and La2O3 powder are mixed according to the set mass ratio, and then CeO2 powder and nano TiC powder are added according to the set ratio, and then the powder is ground.

[0021] Alternatively, the equipment used for the above-mentioned grinding process can be a planetary grinding device.

[0022] Optionally, when grinding the alloy powder using the aforementioned planetary grinding equipment, the grinding method can be as follows: using anhydrous ethanol as a dispersant, stainless steel balls as the grinding medium, a ball-to-material ratio of 8:1, a rotation speed of 300 r / min, a grinding time of 2 h to 4 h, and then sieving the powder to control the particle size of the resulting mixed alloy powder to be between 0.5 μm and 5.0 μm.

[0023] In one possible implementation, the above-mentioned preset conditions include: Under an inert gas atmosphere, the temperature is raised to the first temperature, and the first heat preservation is performed; Then, under a hydrogen atmosphere, the temperature is raised to a second temperature and held for a second time.

[0024] Optionally, the inert gas mentioned above can be argon or nitrogen.

[0025] In one possible implementation, the first temperature is 350℃~420℃, for example, 350℃, 380℃ and 420℃, and the duration of the first heat preservation is 2.0h~3.0h; the second temperature is 550℃~620℃, for example, 550℃, 580℃ and 620℃, and the duration of the second heat preservation is 2.0h~2.5h.

[0026] It should be noted that during the preparation of the alloy mixed powder under the aforementioned preset conditions, firstly, in an inert gas atmosphere, the temperature is raised to a first temperature and held for the first time. During this process, volatile impurities such as moisture, ethanol, and oil adsorbed on the surface of the alloy mixed powder can be volatilized and removed, and the inert gas atmosphere can prevent the alloy powder from being oxidized. After holding at 350℃~420℃ for 2.0h~3.0h, the van der Waals forces between the powder particles can be broken through the thermal vibration effect, achieving uniform dispersion of the alloy powder and avoiding the enrichment of TiC or rare earth oxides. In addition, after holding at 350℃~420℃ for 2.0h~3.0h, the crystal forms of La2O3 and CeO2 are stabilized and solidified, while reducing the lattice distortion of Cu powder. In the second stage, under a hydrogen atmosphere at temperatures of 550℃~620℃, hydrogen exhibits strong reducing properties, significantly removing the oxide layer on the surface of the alloy powder. This significantly improves the interfacial compatibility between Cu powder and W powder, rare earth oxides, and nano-TiC. Simultaneously, the temperature of 550℃~620℃ softens and micro-diffused the Cu powder, allowing Cu atoms to diffuse into W powder and La2O. 3、 The CeO2 and nano-TiC powders undergo slight diffusion on their surfaces, forming atomic-level interfacial pre-bonding. This interfacial pre-bonding significantly enhances the bonding force between phase particles in the subsequently pressed skeleton, thereby significantly reducing internal micro-voids after skeleton molding and increasing the initial density of the skeleton.

[0027] The alloy mixed powder prepared under the aforementioned preset conditions exhibits uniform dispersion, no agglomeration or oxidation issues, and high interparticle adhesion. This allows for uniform stress transfer during subsequent pressing and molding, preventing localized porosity or compositional segregation in the pressed CuW contact component skeleton. Simultaneously, the high-purity, non-oxidized W powder contained in the alloy mixed powder demonstrates more thorough metallurgical bonding at the particle necks during vacuum sintering, forming a continuous, dense, and uniform W skeleton network. The skeleton pores have uniform pore size and good connectivity, providing unobstructed channels for subsequent pressure infiltration of Cu liquid, further reducing the final porosity of the component.

[0028] In one possible implementation, the mass ratio of Cu powder, W powder, and La2O3 powder in the above-mentioned alloy mixed powder is 30~50:70~85:0.1~1; the amount of CeO2 powder and nano TiC powder added is 0.05%~0.3% and 0.2%~0.6% of the total mass of Cu powder, W powder, and La2O3 powder, respectively.

[0029] It should be noted that in the aforementioned alloy powder mixture, the W powder accounts for 70% to 85%. This ensures the high melting point, high hardness, and arc erosion resistance of the contact components, forming a continuous and stable W skeleton to support the Cu phase filling. Simultaneously, it leverages the W skeleton's entrapment effect on the Cu phase, fundamentally solving the problems of Cu phase evaporation and splashing during long-term service. This proportion range avoids the problems of insufficient Cu phase filling and decreased conductivity caused by an excessively high W powder content, and also avoids the problems of insufficient skeleton strength and reduced arc resistance caused by an excessively low W powder content. Secondly, the Cu powder accounts for 30% to 50%, which matches the filling ratio of the W skeleton pores. This ensures excellent electrical and thermal conductivity while allowing for sufficient filling of the W skeleton pores by the Cu liquid during pressure infiltration, solving the problems of insufficient density and high porosity in the contact components. Furthermore, this ratio avoids the problems of high-temperature softening and Cu phase enrichment and splashing caused by excessive Cu powder, and also avoids the problems of excessively high contact resistance, poor thermal conductivity, and exacerbated local overheating caused by insufficient Cu powder. In addition, the proportion of La2O3 is 0.1%~1.0%. This proportion has the effect of purifying the Cu-W interface, reducing the interface between the two phases and improving the wettability of Cu-W, solving the problems of weak interface bonding and uneven distribution of copper phase. At the same time, it improves the high-temperature stability of the component and reduces the phenomenon of cracking under thermal cycling. If the proportion is less than 0.1%, it will lead to insufficient interface modification effect. If the proportion is greater than 1.0%, it will lead to problems such as rare earth agglomeration, blockage of W skeleton pores and reduction of conductivity.

[0030] Furthermore, in the technical solution of this invention, CeO2 powder with a mass ratio of 0.05% to 0.3% is added to the alloy mixture of Cu powder, W powder and La2O3 powder. This can form a rare earth synergistic effect with La2O3, and the two complement each other to enhance the effect of interface purification and wettability optimization. At the same time, CeO2 can improve the oxidation resistance of the component and reduce the oxidation and deterioration of Cu and W phases under high temperature arc. If the proportion of CeO2 is >0.3%, it will lead to problems such as a decrease in the conductivity and density of the component. In addition, nano-TiC powder at a mass ratio of 0.2%~0.6% was added. Nano-TiC powder can pin the grain boundaries of Cu and W grains, refine the grains, further optimize the uniformity of copper phase distribution, and inhibit the performance degradation caused by grain growth. At the same time, it can strengthen the W skeleton and Cu-W interface, improve the hardness and deformation resistance of the component, and alleviate the pitting and cracking caused by arc ablation. Furthermore, the trace proportion can avoid the agglomeration of nano-TiC, avoid the local porosity and interface defects caused by agglomeration, and ensure that the density and conductivity of the component are not affected.

[0031] In one possible implementation, the above compression molding includes: The above alloy mixture powder was pre-pressed at 300MPa~400MPa for 25s~30s to obtain a preliminary CuW contact component skeleton; The pre-formed CuW contact component skeleton is placed into a single-cavity hot pressing mold under a vacuum degree ≥10. -3 Under an environment of Pa, a unidirectional pressure of 600MPa~700MPa is applied, and the surface heating zone temperature of the single-cavity hot press mold is adjusted to 550℃~600℃, and the core heating zone temperature is adjusted to 300℃~350℃. Then, the temperature is maintained for 2.0min~3.0min. After the temperature maintenance is completed, the temperature is allowed to cool naturally to room temperature.

[0032] It should be understood that when the surface heating zone temperature of the single-cavity hot pressing mold is 550℃~600℃ and the core heating zone temperature is 300℃~350℃, then the surface heating temperature of the CuW contact material skeleton is 550℃~600℃ and the core heating temperature is 300℃~350℃.

[0033] Optionally, during the pre-compression process described above, the pre-compression equipment can be a cold press.

[0034] Optionally, the aforementioned equipment with a single-cavity hot press mold can be a CNC vacuum unidirectional hot press. The single-cavity hot press mold can be a single-cavity double-layer partitioned heating mold, which is an integrated single-cavity structure. The mold interior can include two independent heating zones, specifically including a cemented carbide single cavity, comprising five basic components: the cavity body, the surface heating zone, the core heating zone, the temperature measuring component, and the demolding ejector pin.

[0035] It should be noted that in the above-mentioned pressing process, the pre-pressing at 300MPa~400MPa for 25s~30s allows for rapid densification and initial forming of the alloy mixed powder, and quickly expels air from the gaps between the powder particles, preventing gas from being trapped and forming internal pores during subsequent hot pressing. Simultaneously, it ensures that the multi-element alloy mixed powder particles are tightly bonded, forming a preliminary skeleton with basic strength, preventing skeleton collapse and component segregation during hot pressing and ensuring the consistency of subsequent hot pressing. Secondly, at a vacuum degree ≥10... -3 At 600 MPa, oxidation of the alloy powder can be avoided, ensuring a high degree of cleanliness at the interface between Cu-W, rare earth, TiC and the matrix. When a unidirectional pressure of 600 MPa to 700 MPa is applied, plastic deformation and tight interlocking of the powder particles can be achieved, significantly improving the initial density of the skeleton. Furthermore, unidirectional pressure can ensure the dimensional accuracy and shape regularity of the skeleton forming, avoiding local porosity caused by multidirectional pressure. At the same time, it allows mechanical interlocking reinforcement between powder particles, improving the overall strength of the skeleton and preventing cracking during subsequent transportation and sintering. Furthermore, during the hot pressing process, maintaining the surface heating zone temperature at 550℃~600℃ matches the softening temperature of the Cu powder, allowing the surface Cu powder to undergo slight plastic flow and diffusion, filling the gaps between the surface powder particles. This achieves a dense, non-porous surface layer of the skeleton, improving the initial flatness of the contact working surface. Simultaneously, maintaining the core heating zone temperature at 300℃~350℃ prevents overheating and agglomeration of the core powder, while ensuring that the core particles are tightly compacted under high pressure. This forms a uniform porous structure with a dense surface and a compact core, avoiding surface pores while retaining interconnected pores in the core, thus facilitating the subsequent pressure infiltration of molten Cu. Domain filling provides unobstructed channels, solving the problem of uneven copper phase distribution; after holding at a temperature of 2.0 min to 3.0 min, micro-diffusion of powder is achieved while avoiding the growth of nano-TiC grains and agglomeration of rare earth oxides caused by prolonged high temperature, thus fully preserving the synergistic strengthening effect of multi-component powders; finally, natural cooling to room temperature can slowly release the thermal and plastic stresses generated during hot pressing, avoiding framework cracking and crystal distortion caused by rapid cooling, while allowing the compacted powder particles to form a stable lattice arrangement, improving the structural stability of the framework and reducing the deformation risk of subsequent vacuum sintering and pressure melting processes.

[0036] In one possible implementation, the above-mentioned vacuum sintering process includes: In a vacuum environment, the temperature is increased to the first sintering temperature at the first rate, and the first sintering holding is performed. Nitrogen gas is introduced at the end of the first sintering holding for 25 to 30 minutes. Then, the temperature is decreased to the second sintering temperature at the second rate, and the second sintering holding is performed. After completion, the temperature is allowed to cool naturally to room temperature.

[0037] Optionally, in the above-mentioned vacuum sintering process, the vacuum degree of the sintering equipment can be ≤5×10⁻⁶. -4 Pa.

[0038] Optionally, the duration of the second sintering and heat preservation can be 1.5h to 2.0h.

[0039] Optionally, during the last 25 to 30 minutes of the first sintering heat preservation, the flow rate of nitrogen gas introduced can be 2.5 L / min to 3.5 L / min.

[0040] In one possible implementation, the first sintering rate is 3℃ / min to 5℃ / min, the first sintering temperature is 1300℃ to 1500℃, for example, 1300℃, 1350℃, 1400℃, 1450℃ and 1500℃, and the duration of the first sintering holding is 2.0h to 4.0h; the second sintering rate is 5℃ / min to 10℃ / min, and the second sintering temperature is 650℃ to 750℃, for example, 650℃, 700℃ and 750℃.

[0041] Optionally, the equipment for the above-mentioned vacuum sintering process can be a high-vacuum segmented temperature-controlled sintering furnace.

[0042] In one possible implementation, the pressure infiltration process described above includes: Hydrogen gas is introduced at a rate of 5 L / min to 10 L / min, and held at a temperature of 400℃ to 600℃ (e.g., 400℃, 450℃, and 500℃) for 2.0 h to 4.0 h under a hydrogen atmosphere. After completion, the equipment pressure is adjusted to 1.0 GPa to 1.5 GPa, and the temperature is simultaneously raised to 950℃ to 1150℃ (e.g., 950℃, 980℃, 1000℃, 1100℃, and 1150℃), held for 1.0 h to 2.0 h, and then allowed to cool naturally to room temperature.

[0043] Optionally, the equipment for the pressure melting and infiltration treatment described above can be a high-pressure hydrogen atmosphere melting and infiltration furnace.

[0044] It should be noted that in the vacuum sintering process described above, in the first stage, a low heating rate of 3℃ / min to 5℃ / min allows sufficient time for heat conduction within the framework, preventing abnormal growth of W grains and agglomeration of rare earth elements or TiC caused by localized overheating. When the temperature reaches 1300℃ to 1500℃, metallurgical bonding occurs at the neck of the W particles, ensuring that the W particles are fully sintered to form a continuous framework without causing excessive density and pore blockage due to excessively high temperatures. Nitrogen gas is introduced at the end of the first stage (25 to 30 minutes). Nitrogen gas can quickly fill the pores of the framework, purify the W grain boundaries, inhibit secondary oxidation of W grains during cooling, and refine the W grains. Simultaneously, a medium cooling rate of 5℃ / min to 10℃ / min is used to cool to 650℃ to 750℃, which avoids thermal stress cracking caused by rapid cooling and allows for crystal stabilization of the W framework at 650℃ to 750℃, further releasing internal stress. Furthermore, during the sintering process, if the temperature in the first stage is below 1300℃, it will lead to insufficient bonding at the necks of W particles, insufficient skeleton strength, and easy collapse during melt infiltration. If the temperature is above 1500℃, it will cause W grains to grow violently, the skeleton to be over-sintered and dense, and the pores to be blocked, preventing subsequent Cu liquid from filling the gaps, directly resulting in uneven copper phase distribution and insufficient density. If the heating rate is greater than 5℃ / min, the rate is too fast, leading to excessive temperature differences between the inside and outside of the skeleton, generating severe thermal stress, causing cracking, and causing the agglomeration of nano-TiC and rare earth oxides in the powder, resulting in the loss of the strengthening effect. Furthermore, in the first stage, if nitrogen is introduced too early, it will hinder the sintering of W particles; if nitrogen is introduced too late, the grain boundary purification and anti-oxidation effects cannot be achieved. In the second sintering stage, if the temperature is below 650℃, stress release and crystal stabilization cannot be completed; if it is above 750℃, it will cause slight softening and deformation of the W skeleton, destroying the uniformity of the pores.

[0045] During the aforementioned pressure melting process, in the first stage, hydrogen gas is introduced at a rate of 5 L / min to 10 L / min to rapidly displace the air inside the furnace and create a stable reducing atmosphere. Holding at 400℃ to 600℃ for 2.0 h to 4.0 h deeply reduces the residual trace oxide layers, such as Cu2O and WO3, on the surface of the W skeleton. xThis process avoids premature melting of Cu powder while allowing hydrogen to fully penetrate the pores of the framework, achieving comprehensive purification. In the second stage, the pressure of the entire equipment is 1.0 GPa to 1.5 GPa, and the temperature is simultaneously raised to 950℃ to 1150℃. During this process, the Cu liquid, driven by high pressure, gradually increases its fluidity as the temperature rises, rapidly penetrating along the interconnected pores of the W framework, achieving a dual benefit of forced filling by pressure and increased fluidity by temperature. Holding at this temperature for 1.0h to 2.0h allows the Cu liquid to fully fill the pores, while simultaneously completing element diffusion at the Cu-W interface, forming a metallurgical bond. During the second stage of pressure infiltration, if the pressure is below 1.0 GPa, the Cu liquid cannot fill the micro-nano pores of the W skeleton, resulting in numerous residual pores and insufficient density. If the pressure is above 1.5 GPa, the ultra-high pressure will cause the formed W skeleton to deform and collapse, destroying the skeleton structure and causing severe segregation of the copper phase. If the temperature is below 950℃, the Cu liquid has poor fluidity and cannot complete the pore filling. If the temperature is above 1150℃, the Cu liquid will excessively vaporize, easily forming pore defects, and the W skeleton will soften at high temperature and cannot withstand high pressure. At the same time, the nano-TiC grains will grow violently and lose the dispersion strengthening effect.

[0046] In one possible implementation, the above annealing process includes: Under an inert atmosphere, the temperature is set to 400℃~600℃, for example, 400℃, 450℃, 500℃, 550℃ and 600℃, and held for 2.0h~4.0h, and then naturally cooled to room temperature.

[0047] Optionally, the equipment for the above-mentioned annealing treatment can be an inert atmosphere constant temperature annealing furnace.

[0048] Optionally, in the above annealing process, the inert gas can be high-purity argon.

[0049] It should be noted that during the above-mentioned preparation of CuW contact components, residual stress will remain inside the contact blank after pressing, vacuum sintering and pressure melting. Therefore, annealing at a temperature range of 400℃~600℃ for 2.0h~4.0h can achieve slow and full release of stress. Furthermore, the inert atmosphere isolates oxidation and natural cooling can further avoid the generation of secondary stress due to excessively rapid cooling, ultimately eliminating the residual stress in the component. Furthermore, an annealing temperature of 400℃~600℃ can gently promote the diffusion between Cu and W atoms at the interface, allowing the Cu-W interface to form a thicker transition layer, further reducing the proportion of physical bonding and significantly increasing the proportion of metallurgical bonding. At the same time, it allows rare earth oxides to be uniformly adsorbed at the Cu-W interface and nano-TiC to pin the grain boundaries, further purifying the interface and reducing the interface energy, ultimately significantly improving the shear strength of the Cu-W interface, thus solving the core problem of weak interface bonding in existing technologies. In addition, the annealing process allows the alloy to rearrange and further refine, thereby inhibiting abnormal grain growth and making the grain size of Cu and W phases more uniform. At the same time, the thermal motion of atoms can fill the micropores inside the billet, further improving the density of the component, and further optimizing the uniformity of the distribution of the copper phase along the W skeleton, without local enrichment or depletion areas.

[0050] To achieve the above objectives, the present invention also provides a CuW contact component, which is prepared by the above-described preparation method.

[0051] In the technical solution of this invention, the relative density of the CuW contact component can reach over 99%, the porosity is <0.5%, and there are no large-sized pores or closed-cell defects, solving the problems of insufficient density and high porosity in existing materials. Simultaneously, in the CuW contact component, the Cu phase is fully filled along the continuous W skeleton, with no local Cu-depleted or Cu-rich regions, significantly improving the uniformity of copper phase distribution and solving the problems of local overheating and uneven conductivity caused by copper phase segregation. Furthermore, the Cu-W, W-La2O3 / CeO2, and W-nano TiC interfaces formed in the CuW contact component have no oxide barrier layer, low interfacial energy, sufficient diffusion, and high interfacial shear strength. At the same time, the component is mainly metallurgically bonded, solving the core problems of weak interfacial bonding and easy peeling. The CuW contact components prepared by this invention have significantly improved electrical and thermal conductivity, and show no significant attenuation during long-term power-on and power-off processes; they have low contact resistance and small drift, solving the problem of easy contact resistance drift; and they can withstand the high-temperature impact of electric arcs, avoiding the problems of high-temperature evaporation and splashing caused by local Cu phase enrichment.

[0052] Example 1 A method for preparing a CuW contact component, comprising: S10. Under preset conditions, alloy mixed powder is prepared, based on S101~S102, as follows: S101. Weigh out Cu powder, W powder and La2O3 powder according to a mixing mass ratio of 30:70:0.1, then add 0.05% CeO2 powder and 0.2% nano TiC powder. Add the mixed powder to a planetary ball mill, use anhydrous ethanol as a dispersant, stainless steel balls as the grinding medium, ball-to-material ratio of 8:1, speed of 300 r / min, and ball mill for 2 hours to obtain the initial mixed powder. S102. The initial mixed powder obtained in S101 is loaded into an atmosphere-protected stepped temperature-controlled heat treatment furnace, and argon gas is introduced to replace the oxygen in the furnace. Then, the temperature is raised to 350°C and held for 3.0 h. After the holding period, the atmosphere in the furnace is switched to high-purity hydrogen gas, and the temperature is raised to 550°C and held for 2.5 h. After the holding period, the temperature is allowed to cool naturally to room temperature to obtain alloy mixed powder. S20. The alloy mixture powder obtained in S10 is pressed and molded to obtain the CuW contact component skeleton, which is realized based on S201~S202, as follows: S201. The alloy mixed powder obtained in S10 is loaded into a pre-pressing mold, placed in a fully automatic powder hydraulic pre-pressing machine, a pressure of 300MPa is applied, the pressure is held for 30s, and after the pressure is released, the mold is demolded to obtain a preliminary CuW contact component skeleton. S202. Place the preliminary shaped CuW contact component skeleton obtained in S201 into a single-cavity hot press mold. After closing the mold, load it into a vacuum gradient hot press forming machine. Start the vacuum unit to evacuate the furnace, ensuring a vacuum degree ≥10. -3 Pa, start the hydraulic system and apply a unidirectional pressure of 600MPa to the mold, and keep the pressure constant; simultaneously start the mold zone heating system, adjust the temperature of the mold surface heating zone to 550℃ and the core heating zone to 300℃, and then keep it at that temperature for 3.0min; after the temperature is kept at that temperature, turn off the heating system, maintain vacuum and pressure until the mold cools down to room temperature naturally, release the pressure, demold, and obtain the CuW contact component skeleton; S30. The CuW contact component skeleton obtained in S20 is subjected to vacuum sintering and pressure melting treatment in sequence to obtain the CuW contact component blank, which is implemented based on S301~S302, as follows: S301. Vacuum sintering treatment: The CuW contact component skeleton obtained in S20 is placed into the graphite crucible of a high vacuum sintering furnace, the furnace door is closed, and a vacuum environment is created inside the furnace; then the heating program is started, and the temperature is increased to 1300℃ at a first rate of 3℃ / min, and the temperature is held for the first sintering for 4.0h; at the end of the first holding time, the nitrogen inlet valve is opened to introduce high-purity nitrogen into the furnace; after the first holding time, the temperature is decreased to 650℃ at a second rate of 5℃ / min, and held for 1.5h; after completion, the heating and nitrogen systems are turned off, and the furnace is allowed to cool naturally to room temperature. After the vacuum is broken, the material is discharged to obtain the sintered CuW contact component blank; S302. Pressure Melting Treatment: The sintered CuW contact component blank obtained in S301 is transferred into the melting chamber of a high-pressure hydrogen atmosphere melting furnace. The furnace door is closed, the hydrogen inlet valve is opened, and high-purity hydrogen is introduced into the melting chamber at a rate of 8 L / min to replace the air in the furnace. After maintaining the hydrogen atmosphere, the heating system is started to raise the temperature to 400℃ and hold for 4.0 h. After completion, the hydraulic system and the heating system are started simultaneously to apply a pressure of 1.0 GPa to the melting chamber and maintain it constant. The temperature is raised to 950℃ at a rate of 10℃ / min. After the temperature reaches the target, it is held for 2.0 h to complete the full filling of the W skeleton by Cu liquid. After the holding period, the heating system is turned off, and the hydrogen atmosphere and pressure are maintained until the furnace cools naturally to room temperature. The pressure is released, the hydrogen supply is stopped, argon gas is introduced for replacement, and the material is discharged to obtain the CuW contact component blank. S40. Anneal the CuW contact component blank obtained in S30 to obtain the CuW contact component, specifically: The CuW contact component blank obtained from S30 is placed into the heat-resistant fixture of the annealing furnace, the furnace door is closed, and high-purity argon gas is introduced to replace the air in the furnace, maintaining a continuous argon atmosphere. The heating system is started and the temperature is raised to 400℃ and held at that temperature for 4.0 hours. After the holding period, the heating system is turned off, and the argon atmosphere is maintained. The furnace is allowed to cool naturally to room temperature. After the material is discharged and the surface is cleaned, the finished CuW contact component is obtained.

[0053] Through steps S10 to S40, the CuW contact component disclosed in this invention is obtained.

[0054] Example 2 A method for preparing a CuW contact component, comprising: S10. Under preset conditions, alloy mixed powder is prepared, based on S101~S102, as follows: S101. Weigh out Cu powder, W powder and La2O3 powder according to a mixing mass ratio of 50:85:1.0, then add 0.3% CeO2 powder and 0.6% nano TiC powder. Add the mixed powder to a planetary ball mill, use anhydrous ethanol as a dispersant, stainless steel balls as the grinding medium, ball-to-material ratio of 8:1, speed of 300 r / min, and ball mill for 4 hours to obtain the initial mixed powder. S102. The initial mixed powder obtained in S101 is loaded into an atmosphere-protected stepped temperature-controlled heat treatment furnace, and argon gas is introduced to replace the oxygen in the furnace. Then, the temperature is raised to 420℃ and held for 2.0h. After the holding period, the atmosphere in the furnace is switched to high-purity hydrogen gas, and the temperature is raised to 620℃ and held for 2.0h. After the holding period, the temperature is allowed to cool naturally to room temperature to obtain alloy mixed powder. S20. The alloy mixture powder obtained in S10 is pressed and molded to obtain the CuW contact component skeleton, which is realized based on S201~S202, as follows: S201. The alloy mixed powder obtained in S10 is loaded into a pre-pressing mold, placed in a fully automatic powder hydraulic pre-pressing machine, a pressure of 400MPa is applied, the pressure is held for 25s, and after the pressure is released, the mold is demolded to obtain a preliminary CuW contact component skeleton. S202. Place the preliminary shaped CuW contact component skeleton obtained in S201 into a single-cavity hot press mold. After closing the mold, load it into a vacuum gradient hot press forming machine. Start the vacuum unit to evacuate the furnace, ensuring a vacuum degree ≥10. -3 Pa, start the hydraulic system and apply a unidirectional pressure of 700MPa to the mold, and keep the pressure constant; simultaneously start the mold zone heating system, adjust the temperature of the mold surface heating zone to 600℃ and the core heating zone to 350℃, and then keep it at that temperature for 2.0min; after the temperature is kept at that temperature, turn off the heating system, maintain vacuum and pressure until the mold cools down to room temperature naturally, release the pressure, demold, and obtain the CuW contact component skeleton; S30. The CuW contact component skeleton obtained in S20 is subjected to vacuum sintering and pressure melting treatment in sequence to obtain the CuW contact component blank, which is implemented based on S301~S302, as follows: S301. Vacuum sintering treatment: The CuW contact component skeleton obtained in S20 is placed into the graphite crucible of a high vacuum sintering furnace, the furnace door is closed, and the furnace is evacuated to a vacuum environment; then the heating program is started, and the temperature is increased to 1500℃ at a first rate of 5℃ / min, and the temperature is held for the first sintering for 2.0h; at the end of the first holding time, the nitrogen inlet valve is opened to introduce high-purity nitrogen into the furnace; after the first holding time, the temperature is decreased to 750℃ at a second rate of 10℃ / min, and held for 1.0h; after completion, the heating and nitrogen systems are turned off, and the furnace is allowed to cool naturally to room temperature. After the vacuum is broken, the material is discharged to obtain the sintered CuW contact component blank; S302. Pressure Melting Treatment: The sintered CuW contact component blank obtained in S301 is transferred into the melting chamber of a high-pressure hydrogen atmosphere melting furnace. The furnace door is closed, the hydrogen inlet valve is opened, and high-purity hydrogen is introduced into the melting chamber at a rate of 10 L / min to replace the air in the furnace. After maintaining the hydrogen atmosphere, the heating system is started to raise the temperature to 600℃ and hold for 2.0 h. After completion, the hydraulic system and the heating system are started simultaneously to apply a pressure of 1.5 GPa to the melting chamber and maintain it constant. The temperature is raised to 1150℃ at a rate of 10℃ / min. After the temperature reaches the target, it is held for 1.0 h to complete the full filling of the W skeleton by Cu liquid. After the holding period, the heating system is turned off, and the hydrogen atmosphere and pressure are maintained until the furnace cools naturally to room temperature. The pressure is released, the hydrogen supply is stopped, argon gas is introduced for replacement, and the material is discharged to obtain the CuW contact component blank. S40. Anneal the CuW contact component blank obtained in S30 to obtain the CuW contact component, specifically: The CuW contact component blank obtained from S30 is placed into the heat-resistant fixture of the annealing furnace, the furnace door is closed, and high-purity argon gas is introduced to replace the air in the furnace, maintaining a continuous argon atmosphere. The heating system is started and the temperature is raised to 600℃ and held at that temperature for 2.0 hours. After the holding period, the heating system is turned off, and the argon atmosphere is maintained. The furnace is allowed to cool naturally to room temperature. After the material is discharged and the surface is cleaned, the finished CuW contact component is obtained.

[0055] Through steps S10 to S40, the CuW contact component disclosed in this invention is obtained.

[0056] The performance of the CuW contact components obtained in Examples 1 and 2 was measured respectively. The measurement methods followed the relevant GB / T standards and the industry testing specifications for electrical contact materials. The test methods were as follows: Density index: The density of the sample was determined by Archimedes' displacement method, and the relative density and porosity were calculated; Mechanical strength: Hardness, measured by Vickers hardness tester (HV10), taking the average value of 5 measuring points on the sample; Bending strength, three-point bending method; Electrical properties: Conductivity, measured by eddy current conductivity meter, with the conductivity of pure copper (58 MS / m) as the benchmark, recorded as relative conductivity; Contact resistance, measured by four-probe method at room temperature and 10 MPa contact pressure, recording the initial value and the drift value after 2000 cycles of power on and off. Ablation performance: The arc ablation test machine was used to simulate the high-voltage switch conditions to determine the corrosion depth, maximum crack length, and statistically analyze the Cu phase sputtering rate. Service life: The high-voltage switch mechanical opening and closing test machine completes 20,000 mechanical opening and closing tests. After the test, the contact resistance, density, and surface crack condition are re-inspected to determine the service stability.

[0057] The test results are shown in Table 1.

[0058] Table 1

[0059] Analysis of the test data in Table 1 shows that the CuW contact components prepared in Examples 1 and 2 exhibit excellent performance, surpassing industry standards in density, mechanical strength, ablation resistance, and service stability. These components address fundamental defects in existing contacts, such as uneven copper phase distribution, weak interfacial bonding, insufficient density, and high porosity, as well as service failure issues like contact resistance drift, pitting cracks, copper phase splashing, and short service life. This is because, in the technical solution of this invention, La2O... 3、 The synergistic effect of CeO2 and nano-TiC achieves interface strengthening, grain refinement, and high-temperature stability in CuW contact components. By preparing alloy mixed powder under preset conditions, powder purification, dispersion to prevent agglomeration, and wettability optimization are achieved. Then, a contact skeleton with high density and uniform porosity is obtained through pressing and molding. In the subsequent vacuum sintering and pressure melting process, metallurgical bonding of the W skeleton and full filling of the Cu phase are achieved. The stress is released by annealing treatment, which further optimizes the performance of the contact components.

[0060] Example 3 A method for preparing a CuW contact component, comprising: S10. Under preset conditions, alloy mixed powder is prepared, based on S101~S102, as follows: S101. Weigh out Cu powder, W powder and La2O3 powder according to a mixing mass ratio of 40:80:0.5, then add 0.1% CeO2 powder and 0.5% nano TiC powder. Add the mixed powder to a planetary ball mill, use anhydrous ethanol as a dispersant, stainless steel balls as the grinding medium, ball-to-material ratio of 8:1, speed of 300 r / min, and ball mill for 3 hours to obtain the initial mixed powder. S102. The initial mixed powder obtained in S101 is loaded into an atmosphere-protected stepped temperature-controlled heat treatment furnace, and argon gas is introduced to replace the oxygen in the furnace. Then, the temperature is raised to 400℃ and held for 2.5h. After the holding period, the atmosphere in the furnace is switched to high-purity hydrogen gas, and the temperature is raised to 600℃ and held for 2.0h. After the holding period, the temperature is allowed to cool naturally to room temperature to obtain alloy mixed powder. S20. The alloy mixture powder obtained in S10 is pressed and molded to obtain the CuW contact component skeleton, which is realized based on S201~S202, as follows: S201. The alloy mixed powder obtained in S10 is loaded into a pre-pressing mold, placed in a fully automatic powder hydraulic pre-pressing machine, and subjected to a pressure of 350MPa. The pressure is held for 30s, and after the pressure is released, the mold is demolded to obtain a preliminary CuW contact component skeleton. S202. Place the preliminary shaped CuW contact component skeleton obtained in S201 into a single-cavity hot press mold. After closing the mold, load it into a vacuum gradient hot press forming machine. Start the vacuum unit to evacuate the furnace, ensuring a vacuum degree ≥10. -3 Pa, start the hydraulic system and apply a unidirectional pressure of 650MPa to the mold, and keep the pressure constant; simultaneously start the mold zone heating system, adjust the temperature of the mold surface heating zone to 580℃ and the core heating zone to 320℃, and then keep it at that temperature for 2.5min; after the temperature is kept at that temperature, turn off the heating system, maintain vacuum and pressure until the mold cools down to room temperature naturally, release the pressure, demold, and obtain the CuW contact component skeleton; S30. The CuW contact component skeleton obtained in S20 is subjected to vacuum sintering and pressure melting treatment in sequence to obtain the CuW contact component blank, which is implemented based on S301~S302, as follows: S301. Vacuum sintering treatment: The CuW contact component skeleton obtained in S20 is placed into the graphite crucible of a high-vacuum sintering furnace, the furnace door is closed, and a vacuum environment is created inside the furnace; then the heating program is started, and the temperature is increased to 1400℃ at a first rate of 4℃ / min, and the temperature is held for the first sintering for 3.0h; at the end of the first holding time, the nitrogen inlet valve is opened to introduce high-purity nitrogen into the furnace; after the first holding time, the temperature is decreased to 700℃ at a second rate of 8℃ / min, and held for 1.0h; after completion, the heating and nitrogen systems are turned off, and the furnace is allowed to cool naturally to room temperature. After the vacuum is broken, the material is discharged to obtain the sintered CuW contact component blank; S302. Pressure Melting Treatment: The sintered CuW contact component blank obtained in S301 is transferred into the melting chamber of a high-pressure hydrogen atmosphere melting furnace. The furnace door is closed, the hydrogen inlet valve is opened, and high-purity hydrogen is introduced into the melting chamber at a rate of 8 L / min to replace the air in the furnace and maintain the hydrogen atmosphere. The heating system is started to raise the temperature to 500℃ and hold for 3.0 h. After completion, the hydraulic system and the heating system are started simultaneously to apply a pressure of 1.2 GPa to the melting chamber and maintain it constant. The temperature is raised to 1050℃ at a rate of 8℃ / min. After the temperature reaches the target, it is held for 1.5 h to complete the full filling of the W skeleton by Cu liquid. After the holding period, the heating system is turned off, and the hydrogen atmosphere and pressure are maintained until the furnace cools naturally to room temperature. The pressure is released, the hydrogen supply is stopped, argon gas is introduced for replacement, and the material is discharged to obtain the CuW contact component blank. S40. Anneal the CuW contact component blank obtained in S30 to obtain the CuW contact component, specifically: The CuW contact component blank obtained from S30 is placed into the heat-resistant fixture of the annealing furnace, the furnace door is closed, and high-purity argon gas is introduced to replace the air in the furnace, maintaining a continuous argon atmosphere. The heating system is started, the temperature is raised to 500℃, and held at a constant temperature for 3.0h. After the holding period, the heating system is turned off, and the argon atmosphere is maintained. The furnace is allowed to cool naturally to room temperature. After discharge, the surface is cleaned to obtain the finished CuW contact component.

[0061] Through steps S10 to S40, the CuW contact component disclosed in this invention is obtained.

[0062] Comparative Example 1 Comparative Example 1 was set up under Example 3. In Comparative Example 1, CeO2 powder and nano TiC powder were not added to the alloy mixed powder in S10, and the S102 step was not performed; S201 was not included in S20; the remaining steps and process parameters were the same as those in Example 3.

[0063] Comparative Example 2 Comparative Example 2 is set up under Example 3. In Comparative Example 2, step S302 is not included in S30; step S40 is not included; the remaining steps and parameters are the same as in Example 3.

[0064] The performance of the CuW contact components obtained in Example 3 and Comparative Examples 1-2 was measured using the same methods as those in Table 1, and the results are shown in Table 2.

[0065] Table 2

[0066] Comparative analysis of the data in Table 2 shows that in Comparative Example 1, the lack of CeO2 powder and nano-TiC powder in the alloy mixed powder led to a large amount of powder agglomeration, blocking the pores of the skeleton. This resulted in uneven and insufficient filling of Cu liquid during the subsequent melting process. Furthermore, without the purification interface of CeO2 powder and the dispersion strengthening of nano-TiC, the Cu-W interface was physically bonded, with coarse grains and weak bonding force, leading to a significant decrease in disassembly strength. The mixed powder was not treated under the preset conditions of this invention, leaving an oxide layer on the powder surface, which increased the contact resistance and drift rate. In Comparative Example 2, the lack of a pressure melting process meant that the W skeleton pores only relied on sintering shrinkage, resulting in a large number of closed pores. The interconnecting pores could not be filled by Cu liquid, leading to the failure of the densification effect. Without subsequent annealing treatment, the residual stress in the component could not be eliminated, leading to stress concentration inside the component, which resulted in a sharp increase in interface contact loss and a significant increase in contact resistance. Ultimately, during use, the arc corrosion resistance depth, crack length, and density retention all faced failure and could not meet the requirements.

[0067] Analysis of Examples 1-3 and Comparative Examples 1-2 shows that in the technical solution of the present invention, Cu powder and W powder in the alloy mixed powder are the matrix core phases, and the rare earth composites of La2O3 and CeO2 and nano-TiC form a triple synergistic effect, which is indispensable. In the subsequent preparation process, the various steps, i.e., the process parameters, do not exist independently, but are matched and synergistic with each other, ultimately improving the performance of CuW contact components.

[0068] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for preparing a CuW contact component, characterized in that, The preparation method includes: Alloy mixed powder was prepared under preset conditions; The alloy mixture powder is pressed and molded to obtain a CuW contact component skeleton; The CuW contact component skeleton is subjected to vacuum sintering and pressure melting treatment in sequence to obtain CuW contact component blank; The CuW contact component blank is annealed to obtain the CuW contact component; The alloy mixed powder includes Cu powder, W powder, La2O3 powder, CeO2 powder, and nano TiC powder.

2. The preparation method according to claim 1, characterized in that, The preset conditions include: Under an inert gas atmosphere, the temperature is raised to the first temperature, and the first heat preservation is performed; Then, under a hydrogen atmosphere, the temperature is raised to a second temperature and held for a second time.

3. The preparation method according to claim 2, characterized in that, The first temperature is 350℃~420℃, and the duration of the first heat preservation is 2.0h~3.0h; the second temperature is 550℃~620℃, and the duration of the second heat preservation is 2.0h~2.5h.

4. The preparation method according to claim 1, characterized in that, The alloy mixed powder comprises Cu powder, W powder and La2O3 powder in a mixing mass ratio of 30~50:70~85:0.1~1; the amount of CeO2 powder and nano TiC powder added is 0.05%~0.3% and 0.2%~0.6% of the total mass of Cu powder, W powder and La2O3 powder, respectively.

5. The preparation method according to claim 1, characterized in that, The compression molding includes: The alloy mixture powder was pressurized at 300MPa~400MPa for 25s~30s to obtain a preliminary CuW contact component skeleton; The pre-formed CuW contact component skeleton is placed into a single-cavity hot press mold under a vacuum degree ≥10. -3 Under an environment of Pa, apply a unidirectional pressure of 600MPa~700MPa, and adjust the surface heating zone temperature of the single-cavity hot press mold to 550℃~600℃ and the core heating zone temperature to 300℃~350℃, and then hold for 2.0min~3.0min; after the holding period, allow it to cool naturally to room temperature.

6. The preparation method according to claim 1, characterized in that, The vacuum sintering process includes: In a vacuum environment, the temperature is raised to the first sintering temperature at the first rate, and a first sintering holding is performed. Nitrogen gas is introduced 25 to 30 minutes at the end of the first sintering holding. Then, the temperature is lowered to the second sintering temperature at the second rate, and a second sintering holding is performed. After completion, the temperature is allowed to cool naturally to room temperature.

7. The preparation method according to claim 6, characterized in that, The first sintering rate is 3℃ / min~5℃ / min, the first sintering temperature is 1300℃~1500℃, and the duration of the first sintering holding is 2.0h~4.0h; the second sintering rate is 5℃ / min~10℃ / min, and the second sintering temperature is 650℃~750℃.

8. The preparation method according to claim 1, characterized in that, The pressure infiltration process includes: Hydrogen gas is introduced at a rate of 5 L / min to 10 L / min, and the temperature is maintained at 400℃ to 600℃ for 2.0h to 4.0h under a hydrogen atmosphere. After completion, the equipment pressure is adjusted to 1.0GPa to 1.5GPa, and the temperature is simultaneously raised to 950℃ to 1150℃ and maintained for 1.0h to 2.0h, and then naturally cooled to room temperature.

9. The preparation method according to claim 1, characterized in that, The annealing process includes: Under an inert atmosphere, the temperature is set to 400℃~600℃ and held for 2.0h~4.0h, then allowed to cool naturally to room temperature.

10. A CuW contact component, characterized in that, The CuW contact component is prepared by the preparation method described in any one of claims 1 to 9.

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