通过集束拉拔技术获得了高强度高电导Cu-Nb微观复合材料,采用SEM及EDS观察分析了4次复合过程中内部Nb芯丝和Cu层的微观形貌变化,Cu/Nb界面的互扩散行为;对不同复合条件下的挤压、拉拔样品,通过XRD测试,表征了芯丝和基体的晶体取向的演变规律;通过HRTEM和反傅里叶变换研究了Cu/Nb的界面结构和晶体学位向关系。研究表明,在极塑性变形条件下,Cu/Nb界面在3次复合出现明显扩散,Cu、Nb逐渐形成丝织构取向,界面存在典型的(111)_(Cu)//(110)_(Nb)取向关系,晶面夹角为18.7°,每6个(111)Cu晶面出现1个晶面错配。
High strength and high conductivity Cu-Nb microcomoposites were fabricated by Accumulative Bundling and Drawing (ABD) process. The microstructure of the composite and interface diffusion were observed during four compositing processes by SEM and EDS Crystal orientation evolution of Nb filaments and Cu matrix were characterized by XRD at extrusion and drawing conditions of different compositing processes. The interface structure and crystal orientation were analyzed by HRTEM and 1FFT. Results show that the diffusion between Cu/Nb interfaces occurs during the 3rd compositing. The texture of Nb fibers is 〈110〉 orientation while for Cu matrix is 〈111〉 orientation after the severe plastic deformation. And atomic planes (111)Cu are parallel to (110)Sb with an angular deviation of 18.7°, which means that a crystal mismatch dislocation appears at interval of every six Cu (111) crystal planes.