Preparation method of copper-tungsten composite material and copper-tungsten composite material

Abstract

The invention discloses a preparation method of a copper-tungsten composite material, which comprises the following steps: material preparation: taking a copper rod and a tungsten rod, and carrying out oil removal and ultrasonic cleaning on the copper rod and the tungsten rod; a tungsten rod is placed in a forming hole of a graphite mold, then a copper rod is placed on the top of the tungsten rod, the bottom end of the copper rod is provided with a circular truncated cone part, and an obtuse angle alpha is formed between the side face of the circular truncated cone part and the side face of the tungsten rod; feeding into a furnace: feeding the graphite mold with the copper rod and the tungsten rod into a vacuum furnace; vacuumizing is conducted, specifically, the vacuum furnace is vacuumized, and the vacuum degree is 10 <-3 >-10 <-5 > Pa; vacuum melting: heating a vacuum furnace to carry out vacuum melting, wherein the melting temperature is 1200-1320 DEG C; keeping high temperature: keeping the temperature at 1200-1320 DEG C for 5-10 minutes; controlled cooling: cooling to obtain a composite material; and post-treatment: carrying out heat treatment and machining on the composite material. Compared with the prior art, preparation of the high-quality copper-tungsten composite material can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of welding technology, and particularly relates to a preparation method of a copper-tungsten composite material and the copper-tungsten composite material. Background Art

[0002] In the field of material connection, the development of welding technology has always promoted the progress of the manufacturing industry. As an advanced welding process, vacuum brazing has been widely used in many high-end manufacturing fields due to its unique technical advantages.

[0003] Vacuum brazing is a brazing process carried out in a vacuum environment. At high temperatures, the filler metal exhibits good wettability and diffusion, and then firmly connects the workpieces together. Since the entire welding process is carried out in a vacuum, the occurrence of oxidation can be effectively avoided, greatly improving the welding quality. This advantage makes vacuum brazing an indispensable connection technology in fields with extremely high requirements for materials and welding quality, such as aerospace, electronic information, precision machinery manufacturing, etc., and is particularly suitable for the connection of high-demand materials and complex structures. However, the vacuum brazing process itself has extremely strict requirements on operating conditions and the state of workpieces. Precise control of process parameters such as temperature, vacuum degree, and holding time is crucial. These process problems remain to be further solved. These problems not only limit the further popularization and application of vacuum brazing technology but also restrict the development of related high-end manufacturing industries. Based on this, this case proposes a preparation method of a copper-tungsten composite material and the copper-tungsten composite material. Summary of the Invention

[0004] The purpose of the present invention is to provide a preparation method of a copper-tungsten composite material and the copper-tungsten composite material, which can achieve the preparation of high-quality copper-tungsten composite materials.

[0005] The above technical purpose of the present invention is achieved through the following technical solutions: A preparation method of a copper-tungsten composite material, comprising the steps of: Material preparation: Take copper rods and tungsten rods, and perform degreasing, ultrasonic cleaning, and removal of impurities and oxide layers on the copper rods and tungsten rods; Molding: First, place the tungsten rod into the forming hole of the graphite mold, and then place the copper rod on top of the tungsten rod. The bottom end of the copper rod has a frustum portion, and an obtuse angle α is formed between the side surface of the frustum portion and the side surface of the tungsten rod; Furnace charging: Send the graphite mold containing the copper rod and tungsten rod into the vacuum furnace; Vacuum pumping: Pump the vacuum furnace to a vacuum degree of 10 -3 -10 -5 Pa; Vacuum melting: Heat up the vacuum furnace for vacuum melting, and the melting temperature is 1200 - 1320 °C; High-temperature holding: Hold at 1200 - 1320 °C for 5 - 10 minutes; Controlled cooling: Obtain a composite material after cooling; Post-treatment: Perform heat treatment and machining on the composite material to obtain the finished product.

[0006] In a preferred embodiment, during the controlled cooling process, the temperature gradient is controlled for cooling.

[0007] In a preferred embodiment, the angle of the obtuse angle α is 160° to 175°.

[0008] In a preferred embodiment, tungsten wires are attached to the tungsten rod, which act on the melted copper to generate vibration and combine with the cooled copper.

[0009] In a preferred embodiment, the tungsten wires are arranged in a spiral shape and wound around the tungsten rod.

[0010] In a preferred embodiment, the spiral diameter of the tungsten wire is smaller than the diameter of the tungsten rod.

[0011] In a preferred embodiment, at least two copper solder joints are provided on the tungsten wire.

[0012] In a preferred embodiment, the length of the tungsten wire is smaller than the length of the formed copper material.

[0013] In a preferred embodiment, the diameter of the tungsten wire is 0.1 - 0.2 mm.

[0014] A copper-tungsten composite material, comprising a tungsten rod and a copper material, wherein the copper material is coated on the tungsten rod and is made by applying the preparation method of the copper-tungsten composite material described above.

[0015] Compared with the prior art, in the material preparation stage of the present invention, the copper rod and the tungsten rod are degreased, ultrasonically cleaned, and impurities and oxide layers are removed, which effectively guarantees the purity of the raw materials, lays a solid foundation for the subsequent preparation of high-quality composite materials, and avoids affecting the welding effect and material properties due to the oil, impurities and oxide layers on the surface of the raw materials. In the steps of loading into the furnace and evacuating to vacuum, the graphite mold with the placed materials is sent into a vacuum furnace, and the vacuum furnace is evacuated to a specific vacuum degree, which creates an oxygen-free environment for the subsequent vacuum melting, effectively avoids oxidation of the materials during the melting process, greatly improves the welding quality, and meets the strict requirements of vacuum brazing for the vacuum environment. In the vacuum melting and high-temperature holding steps, the vacuum furnace is heated to 1200 - 1320 °C and held in this temperature range for 5 - 10 minutes. Precise temperature control and duration control ensure that the copper rod is fully melted, provide conditions for achieving high-quality bonding between copper and tungsten, ensure that copper fully penetrates and avoid the generation of bubbles. After controlled cooling, the composite material is heat-treated and machined to obtain the finished product. Through this series of treatments, the material properties are further optimized to meet the diverse requirements of actual use. The particularly prominent design lies in: the frustum-shaped design at the bottom end of the copper rod enables the molten copper to fall and roll along the surface of the tungsten rod when the copper rod melts. This process can effectively expel the gas adsorbed on the surface of the tungsten rod, avoiding bonding defects caused by bubbles at the copper-tungsten joint after cooling. It greatly improves the bonding quality of the copper-tungsten composite material and breaks through the limitations of the vacuum brazing process in terms of operating conditions and workpiece status. Brief Description of the Drawings

[0016] Figure 1 is the process flow chart of a preparation method of a copper-tungsten composite material according to the present invention.

[0017] Figure 2 is the structural schematic diagram of a copper-tungsten composite material according to the present invention.

[0018] Figure 3 is the placement schematic diagram of the graphite mold and materials applied in a preparation method of a copper-tungsten composite material according to the present invention.

[0019] Figure 4 is Figure 3 the longitudinal sectional structural schematic diagram of the structure shown in

[0020] Figure 5 is Figure 4 the enlarged structural schematic diagram of part A in

[0021] Figure 6 is the placement state schematic diagram of the copper rod and the tungsten rod in a preparation method of a copper-tungsten composite material according to the present invention.

[0022] Figure 7 is the structural schematic diagram of the vacuum furnace applied in a preparation method of a copper-tungsten composite material according to the present invention.

[0023] Figure 8 is the internal structural schematic diagram of the vacuum furnace applied in a preparation method of a copper-tungsten composite material according to the present invention.

[0024] Copper material 1; copper rod 2; tungsten rod 3; tungsten wire 4; graphite mold 5; forming hole 6; vacuum furnace 7. Detailed Embodiments

[0025] The present invention will be further described in detail below with reference to the accompanying drawings.

[0026] This specific embodiment is only an interpretation of the present invention and does not limit the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions as needed, but as long as it is within the scope of the claims of the present invention, it is protected by the patent law. Embodiment 1

[0027] Referring to Figures 1 to 8 , a preparation method of a copper-tungsten composite material, comprising the steps of: Material preparation: Take a copper rod 2 and a tungsten rod 3, and perform degreasing, ultrasonic cleaning, and removal of impurities and oxide layers on the copper rod 2 and the tungsten rod 3; Insert into the mold: First, place the tungsten rod 3 into the forming hole 6 of the graphite mold 5, and then place the copper rod 2 on top of the tungsten rod 3. The bottom end of the copper rod 2 has a frustum portion, and an obtuse angle α is formed between the side surface of the frustum portion and the side surface of the tungsten rod 3; Insert into the furnace: Send the graphite mold 5 with the copper rod 2 and the tungsten rod 3 placed therein into the vacuum furnace 7; Vacuum pumping: Pump the vacuum furnace 7 to a vacuum, and the vacuum degree is 10 -3 -10 -5 Pa; Vacuum melting: Heat up the vacuum furnace 7 for vacuum melting, and the melting temperature is 1200 - 1320 °C; High-temperature holding: Hold at 1200 - 1320 °C for 5 - 10 minutes; Controlled cooling: Obtain a composite material after cooling; Post-treatment: Perform heat treatment and machining on the composite material to obtain the finished product.

[0028] In the material preparation stage of the preparation method of the copper-tungsten composite material in this embodiment, degreasing, ultrasonic cleaning are performed on the copper rod 2 and the tungsten rod 3, and impurities and oxide layers are removed. This effectively guarantees the purity of the raw materials, lays a solid foundation for the subsequent preparation of high-quality composite materials, and avoids affecting the welding effect and material properties due to the oil, impurities, and oxide layers on the surface of the raw materials. In the steps of inserting into the furnace and vacuum pumping, the graphite mold 5 with the materials placed therein is sent into the vacuum furnace 7, and the vacuum furnace 7 is pumped to a specific vacuum degree. This creates an oxygen-free environment for the subsequent vacuum melting, effectively avoids oxidation of the materials during the melting process, greatly improves the welding quality, and meets the strict requirements of vacuum brazing for the vacuum environment. In the vacuum melting and high-temperature holding steps, the vacuum furnace 7 is heated to 1200 - 1320 °C and held in this temperature range for 5 - 10 minutes. Precise temperature control and duration control ensure that the copper rod 2 is fully melted, provide conditions for achieving high-quality bonding between copper and tungsten, ensure that copper fully penetrates and avoid the generation of bubbles. After controlled cooling, the composite material is subjected to heat treatment and machining to obtain the finished product. Through this series of treatments, the material properties are further optimized to meet the diverse requirements of actual use. The particularly prominent design lies in: the frustum-shaped design at the bottom end of the copper rod 2 enables the molten copper to fall and roll along the surface of the tungsten rod 3 when the copper rod 2 melts. This process can effectively expel the gas adsorbed on the surface of the tungsten rod 3, avoiding bonding defects caused by bubbles at the copper-tungsten joint after cooling. It greatly improves the bonding quality of the copper-tungsten composite material and breaks through the limitations of the vacuum brazing process in terms of operating conditions and workpiece status.

[0029] Furthermore, during the controlled cooling process, temperature gradient cooling is controlled. The benefits of gradient cooling are as follows: 1. Regulate the microstructure of the material The thermophysical properties of copper and tungsten are significantly different, and there are large differences in their thermal expansion coefficients. If the cooling rate is uniform, during the cooling process, due to the inconsistent shrinkage degrees of the two materials, large internal stresses will be generated at the interface, resulting in defects in the microstructure. Gradient cooling can reasonably control the cooling rate according to the characteristics of copper and tungsten at different temperature stages. At the high-temperature stage, the cooling rate is appropriately increased to inhibit the precipitation of harmful phases and refine the grains; at the low-temperature stage, the cooling rate is slowed down to allow sufficient time for the internal stress of the material to be released, promoting the full diffusion of atoms, thereby optimizing the microstructure and enhancing the stability of the material. 2. Reduce residual stress During the cooling process, due to the asynchronous shrinkage of copper and tungsten, residual stresses will be formed inside the material. Residual stresses will not only reduce the fatigue strength of the material but may also cause deformation or even cracking of the material during subsequent processing or use. Gradient cooling effectively reduces the residual stress inside the material by gradually adjusting the cooling rate, enabling copper and tungsten to shrink orderly at different stages. This reduction in stress significantly improves the reliability of the material, extends its service life in practical applications, and reduces product failures caused by stress problems. 3. Improve the bonding strength of the material The cooling process has a significant impact on the bonding strength between copper and tungsten. Gradient cooling can form a more stable and continuous metallurgical bond at the interface between copper and tungsten. At the initial stage of cooling, a faster cooling rate promotes the rapid mutual diffusion of copper atoms and tungsten atoms, forming strong chemical bonds; as the temperature decreases, slowing down the cooling rate helps to further improve the interface structure and enhance the interfacial bonding force. This significantly improves the overall bonding strength of the copper-tungsten composite material, meeting the stringent requirements for material properties in the high-end manufacturing field. 4. Ensure product quality consistency In industrial production, the consistency of product quality is crucial. Gradient cooling can reduce the material performance differences caused by fluctuations in cooling conditions by precisely controlling the cooling process. Whether it is a small batch trial or large-scale production, it can ensure the stability of the quality of each copper-tungsten composite material product, improve production efficiency, reduce production costs, and enhance the competitiveness of products in the market.

[0030] In this embodiment, the obtuse angle α is 160° to 175°. Within this angle range, after the copper rod 2 is melted, the path and speed of the copper liquid rolling down the surface of the tungsten rod 3 are more ideal, which is conducive to fully expelling the adsorbed gas on the surface of the tungsten rod 3, greatly reducing the probability of bubbles generated in the copper-tungsten joint, and improving the bonding quality. At the same time, this design can effectively reduce the problem of inconvenience in matching between the copper rod 2 and the tungsten rod 3 caused by unreasonable angles.

[0031] In order to further eliminate the possibility of bubbles between copper and tungsten, a tungsten wire 4 is attached to the tungsten rod 3 to act on the melted copper, generate vibrations, and combine with the cooled copper. When the copper rod 2 is heated and melted in the vacuum smelting stage, the liquid copper flows along the surface of the tungsten rod 3 under the action of gravity. During this process, the copper liquid moves the tungsten wire 4 attached to the tungsten rod 3. This movement causes the tungsten wire 4 to vibrate. On the one hand, the vibration can make it easier for bubbles to escape from the system. On the other hand, it causes disturbances inside the copper liquid, and the gas originally adsorbed on the surface of the tungsten rod 3 is also released, effectively preventing these gases from forming bubbles and remaining at the copper-tungsten joint during the cooling and solidification process. As the copper liquid cools, the tungsten wire 4 combines with the solidified copper, enhancing the connection strength between copper and tungsten.

[0032] Furthermore, the tungsten wire 4 is set to be spiral and wound around the tungsten rod 3. The spiral tungsten wire 4 greatly increases the contact area with the copper liquid, and is also conducive to the generation and transmission of vibration. When the copper rod 2 is melted, the copper liquid will flow along the surface of the tungsten rod 3, which will exert force on various parts of the spiral tungsten wire 4, causing continuous vibration. Compared with ordinary settings, this vibration is more uniform and more efficient, greatly improving the efficiency of bubble discharge and significantly reducing the possibility of bubble residue in the copper-tungsten joint. In terms of bonding strength, the spiral structure allows the tungsten wire 4 to form a tighter and stronger bond with the cooled copper. During the flow process, the copper liquid can fully fill the spiral gap, and after cooling and solidification, it forms a mutually embedded structure, which effectively enhances the mechanical bite and metallurgical bonding between copper and tungsten. In addition, the presence of the spiral tungsten wire 4 guides the flow direction of the copper liquid, making its distribution more uniform, and optimizing the organization and performance distribution inside the composite material.

[0033] In order to allow the tungsten wire 4 to be stably wound around the tungsten rod 3 , the spiral diameter of the tungsten wire 4 is smaller than the diameter of the tungsten rod 3 , so that the tungsten wire 4 can be tightly wound around the tungsten rod 3 .

[0034] In order to further stabilize the tungsten wire 4, at least two copper solder joints are provided on the tungsten wire 4.

[0035] In order to prevent the tungsten wire 4 from exposing the copper material 1, the length of the tungsten wire 4 is less than the length of the formed copper material 1.

[0036] In this embodiment, the diameter of the tungsten wire 4 is 0.1 - 0.2 mm. Such a diameter setting is easily stirred by the copper liquid, efficiently eliminates bubbles, ensures the material quality, and can be fully combined with copper, enhancing the bonding strength and maintaining the process stability. Embodiment Two

[0037] Refer to Figures 1 to 8 , a copper-tungsten composite material, comprising a tungsten rod 3 and a copper material 1, wherein the copper material 1 is coated on the tungsten rod 3 and is made by using the preparation method of the copper-tungsten composite material described in Embodiment One.

[0038] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprises", "comprising" or any other variation thereof is intended to cover a non-exclusive inclusion, such that a process, method, article or terminal device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or terminal device. Without further limitation, the elements defined by the statement "comprising..." or "comprising..." do not exclude the presence of additional elements in the process, method, article or terminal device comprising said elements. In addition, in this article, "greater than", "less than", "exceeding", etc. are understood not to include the present number; "above", "below", "within", etc. are understood to include the present number.

[0039] The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and use the present invention. Those skilled in the art can obviously make various modifications to the embodiments easily and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. A method for preparing a copper-tungsten composite material, characterized in that: Includes steps: Material preparation: take copper rods and tungsten rods, degrease and ultrasonically clean them, and remove impurities and oxide layers; Inserting into mold: First, put the tungsten rod into the forming hole of the graphite mold, and then put the copper rod on the top of the tungsten rod. The bottom end of the copper rod has a truncated cone, and the side of the truncated cone forms an obtuse angle α with the side of the tungsten rod. Entering the furnace: Put the graphite mold with copper rod and tungsten rod into the vacuum furnace; Vacuuming: Vacuum the vacuum furnace to a vacuum degree of 10 -3 -10 -5 Pa; Vacuum melting: Heat up the vacuum furnace for vacuum melting, the melting temperature is 1200-1320℃; High temperature holding: 1200-1320℃ for 5-10 minutes; Controlled cooling: After cooling, a composite material is obtained; Post-processing: Heat treatment and mechanical processing of the composite material to obtain the finished product.

2. The method for preparing a copper-tungsten composite material according to claim 1, characterized in that: In the controlled cooling process, temperature gradient cooling is controlled.

3. The method for preparing a copper-tungsten composite material according to claim 1, characterized in that: The obtuse angle α is in a range of 160° to 175°.

4. The method for preparing a copper-tungsten composite material according to claim 1, characterized in that: The tungsten rod is attached with a tungsten wire, which is used to act on the melted copper, generate vibration, and combine with the cooled copper.

5. The method for preparing a copper-tungsten composite material according to claim 4, characterized in that: The tungsten wire is arranged in a spiral shape and is wound around the tungsten rod.

6. The method for preparing a copper-tungsten composite material according to claim 5, characterized in that: The spiral diameter of the tungsten wire is smaller than the diameter of the tungsten rod.

7. The method for preparing a copper-tungsten composite material according to claim 5, characterized in that: The tungsten wire is provided with at least two copper welding points.

8. The method for preparing a copper-tungsten composite material according to claim 5, characterized in that: The length of the tungsten wire is shorter than the length of the formed copper material.

9. The method for preparing a copper-tungsten composite material according to claim 4, characterized in that: The diameter of the tungsten wire is 0.1-0.2 mm.

10. A copper-tungsten composite material, comprising a tungsten rod and a copper material, wherein the copper material is coated on the tungsten rod, characterized in that: The copper-tungsten composite material is prepared by the preparation method according to any one of claims 1 to 9.

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