镍基单晶蠕变研究：基于晶体塑性的蠕变模型

在镍基单晶合金高温蠕变建模工作的第二部分，通过提出的蠕变材料模型，在晶体塑性理论的变形梯度与滑移系剪切应变率关系的基础上结合不同温度下不同滑移系上的蠕变机理，最终建立起滑移系上行为与材料结构变形的联系。材料本构方程的积分采用了四阶Runge-utta法，并通过对DD3和 CMSX-4两种材料在不同温度,晶体取向和应力水平下的试验曲线进行计算模拟，说明了模型及算法的可行性及对较宽的温度、应力和晶体取向下蠕变行为模拟的能力。

Creep of Ni-based single crystal superalloy : creep model based on crystal plasticity

This paper is second part of the modeling research of creep behavior of single crystal superalloy, a dislocation-based creep model is devoted to creep predictions. The constitutive equations describe the relation between macroscopic strain rate and shear strain rate on slip systems derived from the slip theory and the activity of various slip systems has been modeled by the research of microscopic mechanisms. Results obtained by the present approach are compared with creep date with various temperature and load in different orientations, including superalloys DD3 and CMSX-4, to demonstrate the validity and applicability of the proposed model.