Microstructure Characterization And Mechanical Properties Of Cu-Cr-Zr Alloys Prepared By Aluminothermic Reaction

Cu-Cr-Zr alloy is a type of precipitation-strengthened high-strength and high-conductivity copper alloy with high strength,good electrical and thermal conductivity,corrosion resistance,thermal stability,and ease of processing.It is widely used in integrated circuits.Lead frames,high-speed rail contact materials,asynchronous traction motor rotors,thermonuclear experimental reactors,and high thrust rocket engine combustion chambers are key areas.Cu-Cr-Zr alloy's composition?mass fraction?Cr content of 0.25 wt.%¹.2 wt.%,Zr content of 0.08 wt.%⁰.20 wt.%,hardness?HRB?of 78⁸3,softening temperature of 550°C.With high strength and hardness,good electrical and thermal conductivity,abrasion resistance and abrasion resistance,hardness,strength,electrical conductivity and thermal conductivity are significantly improved after aging treatment,and it is easy to weld.However,the conventional casting method when cast Cu-Cr-Zr is easy to burn out of Cr,the composition is not uniform,the process is complex,and the cost is high.In this paper,the Cu-Cr-Zr alloy prepared by the aluminothermic reaction method is a novel material preparation technology because of its low cost and simple process.The pure copper,glass,Al₂O₃ and graphite were used as substrates in the preparation,and were prepared and explored by different mixing methods.The preparation process of Cu-Cr-Zr alloy was determined as the substrate of graphite substrate and alloy element was placed.Aluminum heat reacts between the bodies to prepare a Cu-Cr-Zr alloy.Cu-Cr-Zr prepared by aluminothermic reaction method was rolled and aged.After tensile test and conductivity test,the results showed that:The total deformation of 30%of the rolled specimen showed a secondary yield during the drawing process.The first yield was 138.96 MPa,the second yield was220.50 MPa,and the tensile strength was 260.80 MPa,60%,and 90%.The yield strengths of the tensile specimens with a deformation amount of 292.10 MPa and361.53 MPa,respectively.The tensile strength reached 324.30 MPa and 397.52 MPa.The elongation after tensile fracture of three different rolling parameters was measured,which was:the elongation of the specimen with 30%deformation was 9.43%,the elongation of the specimen with 60%deformation was 7.54%,and the test of 90%deformation was conducted.The sample elongation was 8.52%.The tensile stress-strain curves after aging at 450°C after rolling for different rolling parameters show that the strength of the aged copper alloys after rolling has been improved,and the30%,60%and 90%rolling tests have been improved.The tensile strength after aging was272.88 MPa,381.61 MPa and 411.65 MPa,respectively.The yield strengths were222.62 MPa,303.14 MPa,and 364.69 MPa,respectively.And the plasticity deteriorates.After 60%of the deformation and 90%of the deformation,the aging of the specimen is improved,and the specimen with 90%of deformation is improved.The elongation rate increased from 8.52%before aging to 25.72%.The elongation at 60%deformation is 13.09%.After the specimens after different deformations were aged,the conductivity showed insensitivity to the amount of rolling deformation,and the decrease in conductivity was not significant.