冲击压缩下陶瓷材料中的破坏波模型

从多晶陶瓷材料细观结构非均匀性及其导致的应力奇异性分析出发，建立了陶瓷材料在冲击压缩下的本构关系,以及以表征材料损伤和破坏的非弹性体积应变为传播特征的破坏波控制方程，破坏层的非弹性体积应变包括由微裂纹成核、扩展引起的膨胀体积应变和由气孔塌陷引起的压缩体积应变两部分．结合92.93%氧化铝陶瓷板碰撞试验，数值模拟了冲击压缩下陶瓷材料中破坏波的传播过程，并对跨越破坏波阵面应力历程和剪切强度的变化规律进行了分析．

Progressive Fragment Modeling of the Failure Wave in Ceramics Under Planar Impact Loading

Polycrystalline ceramics have heterogeneous meso-structures which result in high singularity in stress distribution. Based on this, a progressive fragment model was proposed which describes the failure wave formation and propagation in shocked ceramics. The governing equation of the failure wave is characterized by inelastic bulk strain with material damage and fracture. And the inelastic bulk strain consists of dilatant strain from nucleation and expansion of microcracks and condensed swain from collapse of original pores. Numerical simulation of the free surface velocity was performed in good agreement with planar impact experiments on 92.93 % aluminas at China Academy of Engineering Physics. And the longitudinal, lateral and shear stress histories upon the arrival of the failure wave were predicted, which present the diminished shear strength and lost spall strength in the failed layer.