韧性薄膜/基底体系锥形压痕的有限元分析

Finite Element Analysis of Conical Indentation of Elastic-plastic Film/Substrate Systems

使用量纲分析和有限元法探讨了圆锥性压头压入韧性薄膜/韧性基底体系的力学响应.根据量纲分析,我们建立了压入响应和薄膜及基底的力学参量的无量纲关系.通过对压痕曲线的几个关键变量研究,发现最大压痕荷载取决于压入的深度、薄膜和基底的弹塑性性能,当压入适当深度时初始卸载斜率不受基底的屈服强度的影响.这些结论有利于深入研究韧性薄膜/韧性基底体系的压痕过程,提供了一种从锥形压痕试验中获得薄膜和基底的力学性能的方法.

Dimensional analysis and finite element method（FEM） have been used in this paper to investigate the conical indentation of elastic plastic film/substrate systems.The scaling relationships derived from dimensional analysis bridge the indentation response and the elastic-plastic properties of both film and substrate.Several key variables of an indentation curve are revealed and examined,which can indicate that the maximum indentation force depends on the elastic-plastic properties of both film and substrate and the initial unloading slope is independent on the initial yield stress of the substrate with the moderate indentation depth.The investigation and analysis of this work might be beneficial to understanding deeply the conical indentation of the elastic plastic film/substrate system,and provide a potential way for developing the practicable technique to extract the mechanical properties of both film and substrate from the conical indentation test.