偏应力对材料层裂强度影响的实验研究

 采用热装配方法对平面样品施加径向应力，获得不同程度的偏应力，通过轻气炮实验获得了不同预应力下LY12铝合金层裂信号，结果表明：即使在相同撞击速度下，材料的层裂强度差异也发生明显变化。偏应力越大，材料的层裂强度越小，由于不同的球面层裂具有不同的偏应力场，通过本实验方法有可能将球面层裂与一维平变下的层裂联系起来。

Experiment Research on Spallation Strength under Deviatoric Stress

Overstress assembly by heating is adopted to achieve pre-compression along the radial direction of disk-shaped LY12 Al samples. Different deviatoric stress can be obtained using the assembly methods. The spallation signals of these pre-compressed samples were measured with VISAR in light-gas gun shock experiments. The obtained data show that the pullback amplitudes of the free surface velocity in the samples varied significantly even under the same impact velocity. The material's spallation strength is decreased with the incremental deviatoric stress. This method can be used to investigate the relation between spherical spallation and uniaxial strain spallation.