钽的层裂实验数值模拟

 采用连续介质力学基唯象模型模拟分析了钽的平板撞击层裂行为。该模型包括了材料的非线性弹性（状态方程）、率相关塑性和孔洞的形核及生长等多种效应，并且采用一种对角隐式Runge-Kutta方法来求解本构率方程组，提高了热粘塑性本构关系计算的稳定性及精度。将数值模拟结果和相关实验数据进行了对比分析，结果表明，对于样品中的拉应力峰值明显高于材料层裂强度的实验（中、高速平板撞击实验），理论模型具有较好的预估能力，但对于临界层裂问题（低速平板撞击实验），该模型对材料损伤与失效过程的描述可能不够准确，需要进一步改进。

Numerical Modeling of Spallation Experiments of Tantalum

A phenomenological model,which includes nonlinear elasticity(equation of state),rate-dependent plasticity,and void nucleation and growth,is provided for modeling the spallation behavior of tantalum.An implicit numerical technique,diagonally implicit Runge-Kutta method,is used to solve the constitutive rate-equations,and some improvements to the stability and accuracy of the solution are obtained.The model developed is used to simulate the plate impact experiments on tantalum.Comparisons are made between the model and the experimental data.Results show that close agreement between model predictions and experimental results is obtained for moderate or high velocity plate impact experiments,but some improvements in the model are necessary to predict the damage evolution and failure in incipient spall fracture of tantalum.