滚动接触状态下固体润滑薄膜界面损伤失效行为分析

Analysis on Interface Damage and Failure Behavior of Solid Lubrication Film Under Rolling Contact State

以内聚力模型(CZM)为基础建立薄膜-基体承载系统的有限元分析模型,采用双线性本构关系描述薄膜-基体结合界面的承载及损伤失效行为,通过分析法向和切向载荷作用下界面的承载状态,研究了摩擦因数、薄膜弹性模量、膜厚对薄膜-基体承载系统的界面应力、分离位移、能量释放率的影响,结果表明:摩擦因数增大会导致接触前沿界面承载状态恶化,从而增加界面损伤和脱附失效的风险;薄膜弹性模量增大可以减小接触前沿界面损伤区域和损伤程度,当薄膜弹性模量小于基体弹性模量时界面承载性能急剧恶化;随膜厚增大,界面切向损伤区域和损伤程度先减小后增大,膜厚为0.2倍接触半宽时有利于提升薄膜-基体结合界面的承载性能。

Based on cohesive zone model,a finite element analysis model of film-substrate load system is established.The bilinear constitutive relationship is used to describe the load and damage failure behavior of film-substrate bonding interface.By analyzing the load state of the interface under normal and tangential loads,the influences of friction coefficient,elastic modulus and thickness of film on interfacial stress,separation displacement and energy release rate of the system are studied,the results show that an increase in friction coefficient leads to a deterioration of load state of contact front interface,thereby increasing the risk of interface damage and detachment failure;an increase in elastic modulus of film reduces the damage area and degree of contact front interface,when the elastic modulus of film is smaller than that of substrate,the load performance of the interface deteriorates sharply;as the film thickness increases,the tangential damage area and degree of the interface first decrease and then increase,when the film thickness is 0.2 times of contact half width,it is beneficial to improve the load performance of film-substrate bonding interface.