Lin Liqiang, Zeng Xiaowei
Department of Mechanical Engineering, University of Texas, San Antonio, TX 78249, USA.
Eng Fract Mech. 2015 Jul 1;142:50-63. doi: 10.1016/j.engfracmech.2015.05.039.
The focus of this work is to investigate spall fracture in polycrystalline materials under high-speed impact loading by using an atomistic-based interfacial zone model. We illustrate that for polycrystalline materials, increases in the potential energy ratio between grain boundaries and grains could cause a fracture transition from intergranular to transgranular mode. We also found out that the spall strength increases when there is a fracture transition from intergranular to transgranular. In addition, analysis of grain size, crystal lattice orientation and impact speed reveals that the spall strength increases as grain size or impact speed increases.
这项工作的重点是通过使用基于原子的界面区模型来研究多晶材料在高速冲击载荷下的层裂断裂。我们表明,对于多晶材料,晶界与晶粒之间势能比的增加可能导致断裂模式从沿晶向穿晶转变。我们还发现,当断裂模式从沿晶向穿晶转变时,层裂强度会增加。此外,对晶粒尺寸、晶格取向和冲击速度的分析表明,层裂强度随着晶粒尺寸或冲击速度的增加而增加。