摘要
分别对单晶和多晶原始纯铜进行等通道角挤压(ECAP)实验,研究Bc路径挤压后的组织特征和力学性能.结果表明,单晶和多晶铜在挤压过程中晶粒的细化方式明显不同:单晶铜在位错塞积后形成胞状结构,晶粒在位错塞积区发生断裂是其晶粒细化的主要原因;多晶铜在挤压中发生晶粒转动、晶界移动后造成晶粒被拉长并断裂,这是其晶粒细化的主要原因.力学性能对比发现,挤压中单晶铜的硬度和抗拉强度较多晶铜变化显著,认为挤压后单晶铜亚晶的定向排列是延伸率大幅度提高的主要原因.
The microstructural feature and mechanical response of monocrystal and polycrystal copper subjected to equal channel angular pressing（ECAP） on route Be was studied. Result showed that the grain refinement mechanism was obviously different in monocrystal and polycrystal copper during extrusion process. After piling-up of dislocations, a cellular structure was formed and it led to grain rupture in monocrystal copper, which was the main reasons of grain refinement. In polycrystalline copper, grain rotation and grain boundary movement would result in grain stretch and rupture so that caused the grain refinement. By comparing the mechanic performance, it was showed that the change of hardness and tensile strength of monocrystal copper was more noticeable than that of polyerystal copper. The orientational disposition of subgrain after extrusion was the main cause of extensive increase of elongation rate in monocrystal copper.
出处
《兰州理工大学学报》
CAS
北大核心
2010年第1期1-6,共6页
Journal of Lanzhou University of Technology
基金
兰州市科技局项目(2009-1-9)
兰州理工大学博士基金(SB01200606)的资助
关键词
等通道角挤压
晶界
单晶铜
塑性变形
equal channel angular pressing（ECAP）
grain boundary
monocrystal copper
plastic deformation
