摘要
以弹性变形梯度作为基本变量,结合热力学理论构造了单晶有限变形的热、力耦合计算模型。该模型考虑了温度、变温速率以及塑性耗散等条件对单晶有限变形的影响,相对于传统的以弹性变形梯度为基本变量的晶体塑性模型,算法能够体现温度效应的影响。采用隐式的积分方法对建立的控制方程进行计算以保证求解过程的稳定。以1100Al单晶为例计算了不同升温、降温速率,以及不同应变率影响下的材料应力-应变的响应。结果表明,模型能较好地反映变温过程中,单晶各向异性性质的演化以及应力、应变之间关系的变化。
A thermo-mechanical coupled model based on thermodynamic theory is presented .The elastic deformation gradient was chosen as the basic integration variable in this model .The effects of temper-ature ,temperature changing rate and dissipation of plastic deformation are considered in the finite de-formation computation .Compared to the traditional algorithm with the elastic deformation gradient as its basic variable ,this model can reveal the thermal effects .An implicit integration method was chosen to en-sure the numerical stability .T he effects of different heating/cooling rates and strain rates on stress-strain response of 1100 Al single crystal are computed .The results showed that this model can evaluate the variation of anisotropy and stress-strain response for single crystal deformation with changing tem-perature .
出处
《计算力学学报》
CAS
CSCD
北大核心
2014年第4期501-505,544,共6页
Chinese Journal of Computational Mechanics
基金
国家自然科学基金(10932003
11272075)
国家基础性发展规划(2012CB619603
010CB832700)
国家工信部04重大专项(2011ZX04001-21)资助项目
关键词
单晶体
晶体滑移
热效应
有限变形
single crystal
crystal slip
finite deformation
thermal effects
