脉冲电流处理对拉伸过程中纯铜位错组态的影响  

Effect of electric current pulses on dislocation distribution during the tensile deformation in copper

作　　者：董宇[1] 刘茂林 王新丽[1] Dong Yu;Liu Maolin;Wang Xinli(Instrumental Analysis Center,Northeastern University,Shenyang 110819;Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education),Northeastern University,Shenyang 110819)

机构地区：[1]东北大学分析测试中心,沈阳110819 [2]东北大学材料各向异性教育部重点实验室,沈阳110819

出　　处：《材料与冶金学报》2019年第4期270-273,共4页Journal of Materials and Metallurgy

基　　金：国家自然科学基金面上项目(No.51471047)

摘　　要：通过对退火后的纯铜样品在拉伸过程中施加不同强度的脉冲电流,比较纯铜在不同应变速率下的微观结构的演变,借助透射电子显微镜系统观察不同条件下位错组态的演变.研究结果表明脉冲电流处理后纯铜试样的强度和塑性均降低,透射电镜观察分析发现拉伸过程中施加电流仅是引起位错的增殖和攀移,并没有观察到大量位错的湮灭;拉伸过程中位错的交互作用和交滑移形成大量胞状结构和高密度平面扩展界面.By changing the tensile strain rate during the tensile deformation with electric current passing,Transmission Electron Microscope(TEM)is used to investigate the evolution of the dislocation distribution in Copper.The tensile-elongation results show that the application of electric current causes the simultaneous reduction in the tensile strength and the elongation rate.By TEM analysis,it can be found that the application of electric current just results in the proliferation and climbing of the dislocations without the dislocation annihilation.In addition,the dislocation cell structure carries out in the process of tensile deformation,which forms through dislocation interaction and cross-slip.The high density of the dislocation cell structure formed during current passing will distribute throughout the grains.

关 键 词：拉伸 脉冲电流 纯铜 位错组态 

分 类 号：TG142.1[一般工业技术—材料科学与工程]