基于连续损伤力学的表面涂层损伤模拟

针对传统宏观力学研究涂层问题的局限性,开展了基于损伤力学的表面涂层有限元模拟方法研究。首先建立损伤力学材料模型;然后通过有限元软件ABAQUS提供的子程序(VUMAT)接口,将该材料模型嵌入到ABAQUS求解器;最后对涂层进行数值模拟以分析涂层的力学性能。用该材料模型分析不仅可以得到涂层的应力分布,而且可以得到涂层在载荷作用下的损伤过程。通过研究反力与涂层厚度的关系,提出用裂纹穿透涂层时的反力来衡量涂层的承载能力。此外,还可以根据在一定载荷作用下涂层厚度与裂纹深度的关系得到涂层的临界厚度,进而为涂层厚度设计提供参考。

Simulation of surface coating failure based on continuum damage mechanics

In view of the limitations of traditional macro-mechanics in the surface coating study,the continuum damage mechanics(CDM) was introduced into the finite element analysis of the surface coating.A material model was built based on CDM,and it was embedded in the solver of the software ABAQUS through the user defined subroutine VUMAT of ABAQUS as the interface.A series of numerical simulations were carried out to analyze the mechanical behavior of the coating.By means of the proposed model not only the stress distribution in the coating could be obtained,but also the damage evolution of the coating under loading could be predicted.By studying the relationship between the reaction force and the coating thickness,a concept of a special reaction force corresponding to the crack penetrating the coating thickness was proposed to evaluate the load carrying capacity of the coating.Besides,a critical thickness derived from the relationship between the coating thickness and the crack depth as a reference for coating thickness design.