Copper-chromium contact material with ordered 3D microstructure and preparation method

Abstract

The invention discloses a copper-chromium contact material with an ordered 3D microstructure and a preparation method. The copper-chromium contact material comprises a copper matrix phase and a chromium second phase, the second chromium phase is changed into a skeleton structure in spatial ordered directional arrangement from traditional dispersed distribution, and the copper matrix phase is filled in the chromium skeleton structure and is distributed in a through ordered network structure; the CuCr contact of the ordered structure enables internal current to flow orderly and directionally, so that a magnetic field structure of the ordered structure is generated on the surface of the contact in situ, an effect of restraining or accelerating movement of an electric arc generated in a breaking process is achieved, meanwhile, the ordered three-dimensional Cr framework can keep the structure stable when the surface of the contact is melted, and the contact surface is prevented from being damaged. The problem that the contact resistance is increased due to the fact that Cr particles are segregated towards the surface layer after arcing is solved. When the copper-chromium contact material is used as a medium-high voltage switch contact, the current breaking and arc erosion resistance of the CuCr contact material can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of medium and high voltage switch contact materials, and specifically to a copper-chromium contact material with an ordered 3D microstructure and a preparation method thereof. Background Art

[0002] Copper-chromium (CuCr) alloy has a large breaking current capacity and strong resistance to arc erosion, and is currently one of the most important contact materials for medium- and high-voltage high-power vacuum switches. With the advent of the intelligent era, the requirements for high reliability and low cost are getting higher and higher. The tissue degradation problem of traditional CuCr contacts caused by arc erosion has greatly limited the large-scale application of this material in the field of high-end manufacturing.

[0003] In the traditional CuCr contact material prepared by powder metallurgy, the Cr second phase is dispersed in the Cu matrix in the form of particles. The randomly and independently distributed Cr second phase can enhance the mechanical properties of the contact. However, when the contact is disconnected, the surface temperature of the contact rises sharply, causing the surface Cu to melt. The density difference between the randomly distributed Cr particles and the liquid Cu causes the Cr particles to float on the surface of the molten pool very easily, and easily segregate on the material surface through the flow of the molten Cu melt, resulting in material tissue degradation, causing a significant increase in contact resistance and temperature rise, and even component failure, which seriously affects the corrosion resistance of the contact material. The Chinese invention patent with authorization announcement number CN109261961B discloses a method for preparing a copper-based electrical contact material based on 3D printing technology, the method comprising the following steps: (1) establishing a three-dimensional skeleton model of Cr, and 3D printing; (2) inserting a soft magnetic phase core structure into the three-dimensional Cr skeleton obtained in step (1); and (3) infiltrating a highly conductive phase Cu into the skeleton obtained in step (2). However, the use of soft magnetic phase filaments to assist in generating a magnetic field to drive the arc spot movement has poor autonomy and structural dependence in the generation of magnetic fields, and the effect of improving the breaking current capacity and arc erosion resistance is limited. In addition, this method requires the placement of soft magnetic phase filaments in the Cr three-dimensional skeleton. The additional placement step increases the complexity of the preparation process, which is not only more cumbersome in operation and requires higher process precision, but also increases material and time costs. Summary of the invention

[0004] The purpose of the present invention is to provide a method for preparing a copper-chromium contact material with an ordered 3D microstructure. The internal organizational structure of the copper-chromium contact material of the present invention is composed of a Cr skeleton with an ordered 3D microstructure and a through-distributed Cu conductor. When the switch is powered on, an orderly and directional current can be automatically generated inside the contact, thereby generating a magnetic field with an ordered microstructure in situ on the contact surface. When used as a medium- and high-voltage switch contact, the current breaking and arc erosion resistance capabilities of the CuCr contact material can be improved.

[0005] The technical solution of the present invention is: a copper-chromium contact material with an ordered 3D microstructure, comprising a copper matrix phase and a chromium second phase; the chromium second phase is a skeleton structure with orderly spatial arrangement, and the copper matrix phase is filled in the chromium skeleton structure and distributed in a through-connected ordered network structure.

[0006] The aforementioned method for preparing the copper-chromium contact material having an ordered 3D microstructure specifically comprises the following steps:

[0007] Step 1: construct a model of the ordered 3D Cr skeleton structure;

[0008] Step 2: Prepare a Cr skeleton structure with a spatially ordered 3D microstructure using a 3D printing method;

[0009] Step 3: Use the melt infiltration method to fill Cu into the Cr skeleton structure obtained in step 2 to prepare a CuCr contact material with a spatially ordered 3D microstructure arrangement of the Cr second phase and an interconnected Cu matrix, so that the current can flow along the orderly interconnected Cu phase, thereby generating a magnetic field with an ordered microstructure in situ.

[0010] In the aforementioned method for preparing the copper-chromium contact material with an ordered 3D microstructure, in step 1, the model for constructing an ordered 3D Cr skeleton structure controls the porosity by regulating the skeleton structure characteristics of the Cr skeleton.

[0011] In the aforementioned method for preparing the copper-chromium contact material with an ordered 3D microstructure, in step 2, the Cr powder used in the 3D printing method is a spherical powder of 15-53 μm.

[0012] In the aforementioned method for preparing the copper-chromium contact material with an ordered 3D microstructure, the process of preparing the Cr skeleton structure with a spatially ordered structure by a 3D printing method is specifically prepared by a binder jet 3D printing method or a selective laser melting method.

[0013] In the aforementioned method for preparing the copper-chromium contact material with an ordered 3D microstructure, the binder jet 3D printing method comprises the following steps:

[0014] (1) using a binder jet 3D printing device to print out an ordered 3D microstructure Cr skeleton structure precursor, and this step is performed in an air atmosphere;

[0015] (2) curing the Cr skeleton structure precursor with the ordered 3D microstructure printed in a drying oven, which step is performed under air atmosphere;

[0016] (3) degreasing the solidified ordered 3D microstructured Cr skeleton structure precursor in a sintering furnace, wherein the step is performed in a high-purity argon or high vacuum atmosphere;

[0017] (4) Sintering the degreased Cr skeleton structure precursor with an ordered 3D microstructure in a sintering furnace to obtain an ordered 3D microstructure Cr skeleton structure; this step is performed in a high-purity argon or high vacuum atmosphere.

[0018] In the aforementioned preparation method of the copper-chromium contact material with an ordered 3D microstructure, the proportion of the binder is 10-90%, the thickness of the printed layer is 50-100 μm; the temperature of the curing treatment is 60-180°C, and the curing treatment time is 2-6 hours; the temperature of the degreasing treatment is 500-700°C, and the degreasing treatment time is 1-3 hours; the sintering temperature is 1400-1800°C, and the sintering time is 3-9 hours.

[0019] In the aforementioned preparation method of the copper-chromium contact material with an ordered 3D microstructure, the proportion of the binder is 50%, the thickness of the printed layer is 75 μm; the temperature of the curing treatment is 120°C, and the curing treatment time is 4 hours; the temperature of the degreasing treatment is 600°C, and the degreasing treatment time is 2 hours; the sintering temperature is 1600°C, and the sintering time is 6 hours.

[0020] In the aforementioned method for preparing the copper-chromium contact material with an ordered 3D microstructure, the selective laser melting method is to use a selective laser melting device to print the Cr skeleton structure with an ordered 3D microstructure, and this step is carried out in a high-purity nitrogen atmosphere.

[0021] In the aforementioned method for preparing the copper-chromium contact material with an ordered 3D microstructure, in step three, the infiltration process is to infiltrate the Cu block into the Cr skeleton structure of the ordered 3D microstructure in a high vacuum atmosphere, and the infiltration temperature is 1150-1300°C to prepare a CuCr contact material with an ordered 3D microstructure.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The present invention melts and infiltrates Cu into the Cr network skeleton to form a through Cu matrix phase, so that the Cu conductive phase is spatially ordered, thereby changing the current inside the contact from the traditional disordered flow to the directional flow in the Cu matrix. The ordered directional flow of the current automatically generates a magnetic field of an ordered microstructure on the surface of the contact, which can restrain or accelerate the arc generated during the breaking process, reduce arc ablation on the surface of the contact, and improve the current breaking and arc erosion resistance of the medium and high voltage CuCr contact material. The present invention changes the dispersed Cr second phase in the traditional CuCr contact material into a network structure with a spatially ordered three-dimensional distribution. The Cr second phase with an ordered microstructure can still maintain its own structural stability when it melts on the contact surface, solving the problem of Cr particles segregating to the surface after arcing and causing increased contact resistance. The through Cr micro-network structure can divide and reduce the Cu molten pool generated during the arcing process, absorb and wrap the liquid Cu and suppress its splashing, which helps to maintain the structural stability of the contact material. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the structure of the copper-chromium contact material with an ordered 3D microstructure of the present invention;

[0025] Figure 2 Schematic diagram of the Cr second phase skeleton structure of the ordered 3D microstructure of the present invention. DETAILED DESCRIPTION

[0026] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0027] Embodiment 1: A copper-chromium contact material with an ordered 3D microstructure, comprising a copper (Cu) matrix phase and a chromium (Cr) second phase; the Cr second phase presents a spatially ordered skeleton structure, and the Cu matrix phase is filled in the Cr skeleton structure and distributed in a through ordered network structure.

[0028] In the copper-chromium alloy (CuCr) with an ordered 3D microstructure, the Cu matrix phase and the Cr second phase are the two main phase structures, which together determine the performance of CuCr. The Cu matrix phase is the continuous phase in CuCr, mainly composed of Cu, which determines the electrical conductivity and thermal conductivity of CuCr. The Cr second phase is an ordered continuous phase distributed in the Cu matrix in CuCr, mainly composed of Cr. The main function of the ordered and continuously distributed Cr second phase is to split and reduce the Cu molten pool, absorb and wrap the liquid Cu and suppress splashing. When the contact surface melts, the Cr network can still maintain its own structural stability, thereby improving the stability of the organizational structure, high temperature resistance and arc erosion resistance of CuCr.

[0029] Embodiment 2: This embodiment provides a method for preparing a copper-chromium contact material having an ordered 3D microstructure, which specifically comprises the following steps:

[0030] Step 1: construct a model of the ordered 3D Cr skeleton structure;

[0031] In this embodiment, the model of the ordered 3D Cr skeleton structure is constructed to control the porosity by regulating the skeleton structure characteristics (fiber size, intralayer spacing and interlayer spacing) of the Cr skeleton.

[0032] Step 2: Prepare a Cr skeleton structure with a spatially ordered 3D microstructure using a 3D printing method;

[0033] In this embodiment, the 3D printing method adopts a binder jet 3D printing method, which specifically includes the following steps:

[0034] (1) using a 15 μm spherical powder of Cr powder raw material and a 10% binder jet 3D printing device to print out a 50 μm thick ordered 3D microstructure Cr skeleton structure precursor, and this step is carried out in an air atmosphere;

[0035] (2) curing the Cr skeleton structure precursor with the ordered 3D microstructure printed in a drying oven. This step is carried out in an air atmosphere at a curing temperature of 60° C. for 6 hours.

[0036] (3) degreasing the solidified ordered 3D microstructured Cr skeleton structure precursor in a sintering furnace. This step is performed in a high-purity argon or high vacuum atmosphere. The degreasing temperature is 500° C. and the degreasing time is 3 h.

[0037] (4) Sintering the degreased Cr skeleton structure precursor with an ordered 3D microstructure in a sintering furnace at a sintering temperature of 1400° C. for a sintering time of 9 h to obtain an ordered 3D microstructure Cr skeleton structure, such as Figure 2 As shown; this step is carried out in a high-purity argon or high vacuum atmosphere.

[0038] Step 3: Use the melt infiltration method to fill Cu into the Cr skeleton structure obtained in step 2 to prepare a CuCr contact material with a spatially ordered 3D microstructure arrangement of the Cr second phase and an interconnected Cu matrix, so that the current can flow along the orderly interconnected Cu phase, thereby generating a magnetic field with an ordered microstructure in situ.

[0039] In this embodiment, a Cu block is infiltrated into a Cr skeleton structure with an ordered 3D microstructure in a high vacuum atmosphere at a melting temperature of 1150° C. to prepare a CuCr contact material with a controllable and dense ordered 3D microstructure. Figure 1 shown.

[0040] Embodiment 3: This embodiment provides a method for preparing a copper-chromium contact material having an ordered 3D microstructure, which specifically comprises the following steps:

[0041] Step 1: construct a model of the ordered 3D Cr skeleton structure;

[0042] In this embodiment, the model of the ordered 3D Cr skeleton structure is constructed to control the porosity by regulating the skeleton structure characteristics (fiber size, intralayer spacing and interlayer spacing) of the Cr skeleton.

[0043] Step 2: Prepare a Cr skeleton structure with a spatially ordered 3D microstructure using a 3D printing method;

[0044] In this embodiment, the 3D printing method adopts a binder jet 3D printing method, which specifically includes the following steps:

[0045] (1) using a 3D printing device to print an ordered 3D microstructure Cr skeleton structure precursor with a thickness of 75 μm using a chromium powder raw material of 34 μm spherical powder and a binder with a ratio of 50%, and this step is performed in an air atmosphere;

[0046] (2) curing the Cr skeleton structure precursor with the ordered 3D microstructure printed in a drying oven. This step is carried out in an air atmosphere at a curing temperature of 120° C. for 4 h.

[0047] (3) degreasing the solidified ordered 3D microstructured Cr skeleton structure precursor in a sintering furnace. This step is performed in a high-purity argon or high vacuum atmosphere. The degreasing temperature is 600° C. and the degreasing time is 2 h.

[0048] (4) Sintering the degreased Cr skeleton structure precursor with an ordered 3D microstructure in a sintering furnace at a sintering temperature of 1600° C. for a sintering time of 6 h to obtain an ordered 3D microstructure Cr skeleton structure, such as Figure 2 As shown; this step is carried out in a high-purity argon or high vacuum atmosphere.

[0049] Step 3: Use the melt infiltration method to fill Cu into the Cr skeleton structure obtained in step 2 to prepare a CuCr contact material with a spatially ordered 3D microstructure arrangement of the Cr second phase and an interconnected Cu matrix, so that the current can flow along the orderly interconnected Cu phase, thereby generating a magnetic field with an ordered microstructure in situ.

[0050] In this embodiment, a Cu block is infiltrated into a Cr skeleton structure with an ordered 3D microstructure in a high vacuum atmosphere at a melting temperature of 1220° C. to prepare a CuCr contact material with a controllable and dense ordered 3D microstructure, such as Figure 1 shown.

[0051] Embodiment 4: This embodiment provides a method for preparing a copper-chromium contact material having an ordered 3D microstructure, which specifically comprises the following steps:

[0052] Step 1: construct a model of the ordered 3D Cr skeleton structure;

[0053] In this embodiment, the model of the ordered 3D Cr skeleton structure is constructed to control the porosity by regulating the skeleton structure characteristics (fiber size, intralayer spacing and interlayer spacing) of the Cr skeleton.

[0054] Step 2: Prepare a Cr skeleton structure with a spatially ordered 3D microstructure using a 3D printing method;

[0055] In this embodiment, the 3D printing method adopts a binder jet 3D printing method, which specifically includes the following steps:

[0056] (1) using a 53 μm spherical powder of Cr powder raw material and a 90% binder jet 3D printing device to print out a 100 μm thick ordered 3D microstructure Cr skeleton structure precursor, and this step is carried out in an air atmosphere;

[0057] (2) curing the Cr skeleton structure precursor with the ordered 3D microstructure printed in a drying oven. This step is carried out in an air atmosphere at a curing temperature of 180° C. for 2 h.

[0058] (3) degreasing the solidified ordered 3D microstructured Cr skeleton structure precursor in a sintering furnace. This step is performed in a high-purity argon or high vacuum atmosphere. The degreasing temperature is 700° C. and the degreasing time is 1 h.

[0059] (4) Sintering the degreased Cr skeleton structure precursor with an ordered 3D microstructure in a sintering furnace at a sintering temperature of 1800° C. for a sintering time of 3 h to obtain an ordered 3D microstructure Cr skeleton structure, such as Figure 2 As shown; this step is carried out in a high-purity argon or high vacuum atmosphere.

[0060] Step 3: Use the melt infiltration method to fill Cu into the Cr skeleton structure obtained in step 2 to prepare a CuCr contact material with a spatially ordered 3D microstructure arrangement of the Cr second phase and an interconnected Cu matrix, so that the current can flow along the orderly interconnected Cu phase, thereby generating a magnetic field with an ordered microstructure in situ.

[0061] In this embodiment, a Cu block is infiltrated into a Cr skeleton structure with an ordered 3D microstructure in a high vacuum atmosphere at a melting temperature of 1300° C. to prepare a CuCr contact material with a controllable and dense ordered 3D microstructure. Figure 1 shown.

[0062] Embodiment 5: This embodiment provides a method for preparing a copper-chromium contact material having an ordered 3D microstructure, which specifically comprises the following steps:

[0063] Step 1: construct a model of the ordered 3D Cr skeleton structure;

[0064] In this embodiment, the model of the ordered 3D Cr skeleton structure is constructed to control the porosity by regulating the skeleton structure characteristics (fiber size, intralayer spacing and interlayer spacing) of the Cr skeleton.

[0065] Step 2: Prepare a Cr skeleton structure with a spatially ordered 3D microstructure using a 3D printing method;

[0066] In this embodiment, the 3D printing method uses a selective laser melting device to print an ordered 3D Cr skeleton structure, such as Figure 2 As shown, this step is carried out in a high-purity nitrogen environment, wherein the Cr powder raw material is a 34 μm spherical powder;

[0067] Step 3: Use the melt infiltration method to fill Cu into the Cr skeleton structure obtained in step 2 to prepare a CuCr contact material with a spatially ordered 3D microstructure arrangement of the Cr second phase and an interconnected Cu matrix, so that the current can flow along the orderly interconnected Cu phase, thereby generating a magnetic field with an ordered microstructure in situ.

[0068] In this embodiment, a Cu block is infiltrated into a Cr skeleton structure with an ordered 3D microstructure in a high vacuum atmosphere at a melting temperature of 1220° C. to prepare a CuCr contact material with a controllable and dense ordered 3D microstructure, such as Figure 1 shown.

[0069] like Figure 1 and Figure 2 As shown, an intelligent copper-chromium contact material with an ordered 3D microstructure of the present invention comprises a Cr skeleton structure with an ordered 3D microstructure and a Cu matrix filled in the Cr skeleton structure in an orderly and through arrangement. Compared with the CuCr contact material with a dispersed and disordered microstructure prepared by the traditional powder metallurgy method, the internal microstructure of the contact material of the present invention is that the Cr second phase is arranged in a spatially ordered structure inside the CuCr contact, and the Cu filled in the Cr network is also arranged in an orderly and through manner. This kind of ordered microstructure changes the typical characteristics of the dispersed and random distribution of the conductive Cu phase and the non-conductive Cr phase inside the traditional CuCr contact, so that when the contact material is energized, electrons can flow in a directional manner in the Cu network, forming an ordered and directional current, thereby generating an ordered structure magnetic field on the contact surface in situ that constrains or accelerates the arc, greatly improving the current breaking and arc erosion resistance capabilities of medium and high voltage CuCr contacts.

[0070] The present invention melts and infiltrates Cu into the Cr network skeleton to form a through Cu matrix phase, so that the Cu phase is spatially ordered, thereby changing the current inside the contact from the traditional disordered flow to the directional flow in the Cu matrix. The ordered directional flow of the current automatically generates a magnetic field of an ordered microstructure on the surface of the contact, which can restrain or accelerate the arc generated during the breaking process, reduce arc ablation on the surface of the contact, and improve the current breaking and arc erosion resistance of the medium and high voltage CuCr contact material. The present invention changes the dispersed Cr second phase in the traditional CuCr contact material into a network structure with a spatially ordered three-dimensional distribution. The Cr second phase with an ordered microstructure can still maintain its own structural stability when it melts on the contact surface, solving the problem of Cr particles segregating to the surface after arcing and causing increased contact resistance. The through Cr micro-network structure can divide and reduce the Cu molten pool generated during the arcing process, absorb and wrap the liquid Cu and suppress its splashing, which helps to maintain the structural stability of the contact material.

[0071] In summary, the internal organizational structure of the copper-chromium contact material of the present invention is composed of a Cr skeleton with an ordered 3D microstructure and a through-distributed Cu conductor. When the switch is energized, an orderly and directional current can be automatically generated inside the contact, thereby generating an in-situ magnetic field with an ordered microstructure on the contact surface. When used as a medium- and high-voltage switch contact, the current breaking and arc erosion resistance capabilities of the high-voltage CuCr contact material can be improved; at the same time, the ordered three-dimensional Cr skeleton can maintain its own structural stability when melting on the contact surface, thereby solving the problem of Cr particles agglomerating to the surface after arcing and the resulting increase in contact resistance.

Claims

1. A copper-chromium contact material with an ordered 3D microstructure, characterized in that: It comprises a copper matrix phase and a chromium second phase; the chromium second phase presents a spatially ordered skeleton structure, and the copper matrix phase is filled in the chromium skeleton structure and is distributed in a through-connected ordered network structure.

2. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 1, characterized in that: The specific steps include: Step 1: Construct a model of the ordered 3D chromium skeleton structure; Step 2: Prepare a chromium skeleton structure with a spatially ordered 3D microstructure using a 3D printing method; Step 3: Use the melt infiltration method to fill copper into the chromium skeleton structure obtained in step 2 to prepare a copper-chromium contact material with a spatially ordered 3D microstructure arrangement of the chromium second phase and an interconnected copper matrix, so that the current can flow along the orderly interconnected copper phase, thereby generating a magnetic field with an ordered microstructure in situ.

3. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 1, characterized in that: In step 1, the model of constructing an ordered 3D chromium skeleton structure controls the porosity by regulating the skeleton structure characteristics of the chromium skeleton.

4. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 1, characterized in that: In step 2, the chromium powder used in the 3D printing method is 15-53 μm spherical powder.

5. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 1, characterized in that: The process of preparing a chromium skeleton structure with a spatially ordered structure by a 3D printing method is specifically to prepare it by a binder jet 3D printing method or a selective laser melting method.

6. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 5, characterized in that: The binder jetting 3D printing method comprises the following steps: (1) using a binder jet 3D printing device to print out an ordered 3D microstructured chromium skeleton structure precursor, and this step is performed in an air atmosphere; (2) curing the chromium skeleton structure precursor with the ordered 3D microstructure printed in a drying oven, and this step is performed under an air atmosphere; (3) degreasing the solidified ordered 3D microstructured chromium skeleton structure precursor in a sintering furnace, wherein the step is performed in a high-purity argon or high vacuum atmosphere; (4) Sintering the degreased chromium skeleton structure precursor with an ordered 3D microstructure in a sintering furnace to obtain a chromium skeleton structure with an ordered 3D microstructure; this step is performed in a high-purity argon or high-vacuum atmosphere.

7. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 6, characterized in that: The ratio of the binder is 10-90%, and the thickness of the printed layer is 50-100 μm; the temperature of the curing treatment is 60-180° C., and the time of the curing treatment is 2-6 hours; the temperature of the degreasing treatment is 500-700° C., and the time of the degreasing treatment is 1-3 hours; the sintering temperature is 1400-1800° C., and the sintering time is 3-9 hours.

8. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 7, characterized in that: The ratio of the binder is 50%, and the thickness of the printed layer is 75 μm; the temperature of the curing treatment is 120° C., and the curing treatment time is 4 hours; the temperature of the degreasing treatment is 600° C., and the degreasing treatment time is 2 hours; The sintering temperature is 1600° C. and the sintering time is 6 hours.

9. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 5, characterized in that: The selective laser melting method is to use a selective laser melting device to print an ordered 3D microstructured chromium skeleton structure, and this step is performed in a high-purity nitrogen atmosphere.

10. The method for preparing the copper-chromium contact material with an ordered 3D microstructure according to claim 6 or 9, characterized in that: In step three, the infiltration process is to infiltrate a copper block into a chromium skeleton structure with an ordered 3D microstructure in a high vacuum atmosphere at a temperature of 1150-1300° C. to prepare a copper-chromium contact material with an ordered 3D microstructure.

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