摘要
基于率相关的晶体塑性滑移理论,论文考虑晶体内部塑性变形产生的热以及快速热冲击作用下温度急剧变化产生热应力的热-力双向耦合效应,建立起微观单晶的瞬态热-弹-塑性耦合模型,推导出与温度有关的剪应变率和弹塑性切模量公式.根据论文建立的模型,对ABAQUS软件进行二次开发[1],数值模拟出<001>/{100}单晶Cu在单轴拉伸状态下的应力、应变与温度的关系和弹性模量的变化,结果如下:轴向应力随温度升高先呈线性增加再呈非线性减小,轴向应变随温度增加而增加;弹性模量随塑性变形的增加而降低,与分子动力学模拟的趋势[2]是一致的.数值实验表明,论文建立的模型和算法是正确合理的,且计算量远远小于分子动力学模拟.
This paper presents the thermo-mechanical coupled model of single crystal based on rate-dependent plastic slip deformation theory and its FEM algorithm.The model includes two aspects：one is irreversible heat resulted by plastic deformation and another is a large amount of thermal stress from temperature changing under rapid thermal shock effect.Formulas of shear strain rate and shear modulus dependent on temperature are also given,and the subroutines to calculate stress and strain are coded based on ABAQUS software.The relations among stress,strain and temperature of 001/{100} single crystal copper under tension conditions are calculated by the model established.The results show that true stress are proportional to temperature at first and then nonlinear decreasing but true strain are increased with temperature increasing,so elastic modulus decreases with increasing plastic deformation.The numerical results are consistent with those simulated by molecular dynamics.It shows that the model and its FEM algorithm are reasonable,and their computing costs are less and less than MD simulation.
出处
《固体力学学报》
CAS
CSCD
北大核心
2012年第1期32-38,共7页
Chinese Journal of Solid Mechanics
基金
国家重点基础研究973计划(2010CB832702)
国家自然科学基金项目(90916027)资助
关键词
晶体塑性
热力耦合
有限应变
有限元计算
crystal plasticity
thermo-mechanical coupled
finite strains
FEM computation.
