摘要
对TiN/WC-Co涂层刀具的划痕试验的损伤过程进行仿真计算得到临界载荷并且与划痕试验结果进行比较来确定涂层与基体之间的界面结合强度。得出以下结论:对TiN这样的硬质涂层,其主要损伤破坏形式是:位于压头后方的涂层表面受到拉应力的作用先发生破坏,并逐渐扩展,导致涂层表面横向裂纹的产生,最终涂层断裂。而基体靠近界面处先发生破坏,并逐渐扩展,最终导致基体破坏;涂层的最大拉应力是导致涂层断裂破坏的主要因素,而界面剪应力是导致界面脱开和基体破坏的主要因素。在考虑涂层/基体界面破坏、涂层、基体的损伤情况下,可以有效进行划痕试验的数值模拟,并可获得涂层界面结合强度、损伤的发生发展、涂层失效方式等重要参数。
The damage process of the scratch test of TiN/WC-Co coating cutting tool was simulated by finite element analysis.The interface strength between the coating and the substrate was defined by comparing the simulation results with the scratch test results.The following conclusions were drawn by analyzing and comparing the simulation results.The surface behind the indenter is damaged first and it expands.Then transverse cracks occurr in the coating surface.The coating crack appears in the last.The substrate in the interface is damaged first,and expands then.The max pull stress is the main factor of coating cracking.The interface shear stress is the main factor of delamination and substrate damage.Therefore,taken interface damage,coating damage and substrate damage into consideration,the scratch test can be simulated availably,and the interface strength,damage occurring and developing,and the damage modes can be obtained.
出处
《机械科学与技术》
CSCD
北大核心
2010年第7期940-943,共4页
Mechanical Science and Technology for Aerospace Engineering
基金
教育部重点科技项目(103144)
四川省青年科技基金项目(2006-05-0143)资助
关键词
涂层
划痕
有限元分析
损伤
界面结合强度
thin films
scratch
finite element analysis
damage
interface strength
