中文摘要：

关注循环载荷作用下晶体滑移变形中的非线性硬化现象，用改进的晶体塑性模型刻画单晶金属在循环载荷作用下的变形机理。通过试验和数值模拟，研究单晶铜在循环载荷作用下的Bauschinger效应、滞回特性和循环硬化等循环塑性现象。所得结果表明，文中提出的模型可以有效地描述单晶金属在循环载荷下的非线性变形过程，可以与有限元方法结合，用数值模拟再现试样在循环加载中的Bauschinger效应、滞回特性和循环硬化等塑性变形行为。

英文摘要：

The mechanical behaviours of the single crystal Copper were investigated experimentally under cyclic symmetric loading, in the tests Bauschinger effect could be observed evidently. In order to study the deformation mechanism of single crystal materials under cyclic loading, the classical crystal plasticity （CP） model was modified, by considering kinematic hardening, to describe the non- linear slipping of the slip system of single crystal. Furthermore, the modified model was implemented in the user-defined material subrou- tine associated with the finite element software ABAQUS. After the corresponding material parameters were calibrated by fitting the experimental curves, the numerical simulations using the proposed method were validated by comparing with the experimental results, the phenomena dealing with cyclic plasticity, including Banschinger effect, hysteresis loops and cyclic hardening of single crystal Copper. The results confirmed that the modified CP model is capable of describing the combined and complicated hardening process of single crystal under cyclic loading.