中文摘要：

利用表面机械研磨（SMAT）技术在纯铜表面制备出梯度结构（GS）层,并且通过改变表面机械研磨的试验温度,研究不同变形温度对纯铜组织及力学性能的影响。利用显微硬度计、拉伸试验机、光学显微镜等仪器对液氮下表面机械研磨（LN-SMAT）样品和室温下表面机械研磨（R-SMAT）样品的组织及力学性能进行测试分析。结果表明,LN-SMAT样品的表面硬度及屈服强度更高、梯度结构层厚度更厚,且两种样品的均匀伸长率基本相同,说明低温下表面机械研磨的强化效果更为明显;LN-SMAT样品存在大量孪晶,R-SMAT样品的制备过程可能发生动态回复及动态再结晶。

英文摘要：

By using surface mechanical attrition treatment（ SMAT）,a gradient structure（ GS） was obtained in the surface layer of pure copper samples. Effect of deformation temperature on microstructure and mechanical properties of pure copper was studied by changing the deformation temperature. The microstructure and the mechanical properties of SMAT samples were analyzed by means of micro-hardness test,tensile test,optical microscopy,etc. The results show that the LN-SMAT samples＇ hardness and yield strength is higher and the thickness of GS layer is thicker than that of R-SMAT samples,the uniform elongation of two kind of samples are basically the same,it indicates that SMAT at low temperature have more significant reinforcement effect. The microstructure observation results show that LN-SMAT samples have plentiful twins,the recrystallization may have happen during R-SMAT processing.