Microstructure And Properties Of Cu-1.6Ni-1.2Co-0.65Si Alloy

Cu-1.6Ni-1.2Co-0.65 Si alloy is one of the Cu-Ni-Si alloy materials with excellent comprehensive properties developed at present.Based on the fixed ratio of predecessors,this paper uses metallographic structure,SEM microscopic The properties and microstructures of Cu-1.6Ni-1.2Co-0.65 Si alloy were studied by means of microstructure,TEM microstructure observation,EBSD microtexture,XRD macroscopic preferred orientation,mechanical properties and electrical properties.The temperature of complete recrystallization,and the evolution of texture in the processes of solution,cold rolling,aging,etc.,explore the performance improvement of secondary rolling,and draw the following conclusions:In terms of recrystallization temperature(1)Under different heat treatment process conditions,the complete recrystallization temperature of the water cooling process is the highest,around750 ℃,followed by water cooling + aging,the complete recrystallization temperature is around 650 ℃,and the complete recrystallization temperature with the furnace cooling process is the lowest,at 600 ℃ nearby.(2)After the alloy is kept at 950℃ for 1h and water-cooled,the greater the deformation amount of unidirectional cold rolling,the lower the complete recrystallization temperature of the alloy.At 75% deformation,the complete recrystallization temperature of the alloy is around 750℃,and 50% deformation The complete recrystallization temperature of the alloy is around 800 ℃;25%deformation is still not completely recrystallized at 800 ℃.(3)At the same 75% rolling rate,circumferential rolling can provide more shear bands,which help grain nucleation,and 75% circumferentially rolled alloys complete recrystallization at around 700 ℃.The recrystallization temperature is lower than 75%unidirectional cold rolling.The evolution of texture during preparation(1)The texture components of the solid solution sample of the alloy are mainly Brass texture,Goss texture,S texture and a small amount of Copper texture of α fiber texture.Direct aging treatment after solid solution does not change the texture types of the samples,but will significantly reduce the strength of Brass texture and slightly enhance the strength of Copper texture.(2)With the increase of unidirectional cold rolling deformation,Brass texture will gradually replace other original textures,and the overall texture density increases,and the circumferential cold rolling and unidirectional cold rolling texture The structure types are the same,but the extreme density strength is slightly lower.The increase of the hardness of the alloy by work hardening is positively related to the increase of the extreme density of Brass texture.(3)The type of alloy texture remains unchanged at the initial stage of aging at500 ℃,and the overall texture density increases slightly.With the prolongation of aging time,the extreme density of the overall texture gradually decreases,and the texture types tend to be dispersed.During the aging process,the trend of the texture pole density increasing first and then decreasing is the same as that of the hardness;with the increase of the aging temperature,the cold-rolled samples recrystallized and the grains grew,the Brass texture tends to be dispersed,and the strength Gradually weakened,the recrystallized texture formed and gradually concentrated,and the extreme density intensity gradually increased.Alloy properties of different rolling methods(1)Compared with unidirectional rolling,circumferential rolling has better comprehensive properties.The best process for circumferential rolling is solid solution(980℃+1h,water cooling)+50% circumferential cold rolling+500℃,1h aging,hardness and conductivity of 258.8HV and 42.24%IACS.