Microstructure And Properties Of Cu Alloy Processed By Cryorolling

Copper alloys boasts have excellent conductivity,ductility,and thermal conductivity,but low their strength is low.Therefore,how to increase its their strength and maintain high conductivity becomes our focusthe hot topic of this field without significantly sacrificing their high electrical conductivity.In present work,the effect of rolling on microstructure of CuMg and CuCrZr alloys with different states was investigated by scanning electron microscopy(SEM),transmission electron microscopy(TEM),electron backscattering diffraction(EBSD)and X-ray diffraction(XRD).The mechanical properties were investigated by tensile machine and hardness measurements.The electrical conductivity is studied by electrical conductivity meter.The emphasis is placed on the effect of cryorolling and room temperature rolling on microstructure and properties of Cu alloys.Microstructure of CuMg alloy processed by rolling is characterized by the elongated long grains,high density dislocations and twin layers.As compared to the sample processed at room temperature,cryorolled CuMg alloy may achieve better grain refinement and more twin layers.The texture of CuMg alloy processed at room temperature for 90% is mainly Copper,Brass and S type,of which cryorolled CuMg alloy is Brass type.The hardness,strength and uniform elongation of the cryorolled sample are larger than the sample processed at room temperature.This can be ascribed to the finer grains and more twins in the former.After softening process,the strength decreases and the elongation increases due to the recovery and recrystallization.The electron electrical conductivity of cryorolled sample is below that of the sample processed at room temperature.Microstructure of cryorolled CuCrZr alloy is characterized by the finer grains and more twins.After the initially aged sample was rolled,the amount of twins is less than that of the initially solution-treated sample.For the initially solution-treated sample,the texture of the sample processed at room temperature for 90% is Brass and Copper type,of which the cryorolled sample is Goss and Brass type.For the initially aged sample,the texture of the sample processed at room temperature for 90% is Copper and Goss type,of which the cryorolled sample is Goss and Brass type.After cryorolling,the strength and uniform elongation of initially solution-treated and aged CuCrZr alloy are larger than that of thesample processed at room temperature.The softening process can improve the strength,but reduce the uniform elongation.The electron conductivity of cryorolled solution-treated sample is almost the same as that of the sample processed at room temperature.After softening process,the electron conductivity is increased.