为了研究晶界的压痕行为, 采用晶体塑性理论对单晶和双晶的压痕行为进行了有限元模拟, 得到了压痕表面和晶界位置处的应力分布. 结果表明, 相邻晶粒的晶体取向对压痕深度-载荷响应以及分解切应力分布均有较显著的影响. 压载荷作用下, 晶界位置处存在应力集中, 且晶体取向差异越大, 晶界应力越大.

In the past decades, the indentation test has been widely used to determine the mechanical properties of materials. For the micro- or nano- indentation, the indentation response is complex since only one or two grains can be indented by the indenter. In order to investigate the indentation behavior of the grain boundary, the crystal plasticity theory was implemented into finite element model to simulate the indentation behavior of single crystals and bicrystals. The stress distributions on the indented surface and grain boundary were obtained. The results showed that the crystallographic orientations of the neighboring grains had a remarkable influence on the depth-load response and the resolved shear stress distribution of the indented bicrystals. Under the indentation load, stress concentration occurred at the grain boundary, and the stress at the grain boundary increases with the increase of mis-orientation angle of the two neighboring grains.