冲击相边界传播过程中梯度材料的形成

 采用一种基于简单混合物模型的本构，研究了不可逆相变材料中一维的冲击相边界的传播规律，发现在突加载荷并连续卸载的应力边界条件下，样品内部有梯度材料形成。分析了边界条件对材料梯度变化的影响，并且用基于特征线的数值方法计算了不同的边界条件下材料的梯度分布，从而提出利用冲击相边界的传播制备梯度材料的可能性。最后对这种方法的利弊做了探讨。

Formation of Functionally Graded Material during the Propagation of Phase Boundary under Shock Loading

The propagation of shock-induced phase boundary in a material undergoing irreversible phase transition was studied theoretically using a model based on simple-mixture rule.It was found that along with the decay of the phase boundary,the functionally graded material (FGM) formed in the mixed-phase region.Such FGMs are composed of original phase and product phase,and the composition and physical properties are changing continuously with the coordinate without apparent macro-interfaces between two phases.The effect of stress boundary conditions of impact loading on the grade and range of the FGM region was investigated in detail with a numerical method.Finally,the possibility of producing FGMs with impact method was proposed and the limit of this method has been discussed.