基于弹塑性滚动接触疲劳法评价硬质薄膜结合强度  

Evaluation of Hard-Coating/Substrate Interfacial Adhesion in Rolling Contact Fatigue Method under Elastic-Plastic Deformation

作　　者：邱龙时 朱晓东[1] 鲁莎[1] 李雁淮[1] 徐可为[1] 

机构地区：[1]西安交通大学金属材料强度国家重点实验室,西安710049

出　　处：《真空科学与技术学报》2015年第11期1380-1384,共5页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金资助(项目号51371136);等离子体动力学重点实验室基金项目资助

摘　　要：滚动接触疲劳法表征结合强度的剪切应力幅是一个对界面因素敏感,而对非界面因素不敏感的力学参量,能真实反映膜基结合状态,是较为合理的动态结合强度评价方法。但由于应力计算的模型采用弹性力学方法,对膜基结合强度较高而厚度很小的薄膜,往往加大载荷也较难使膜基界面发生分离。本文采用小直径、高弹性模量Al_2O_3球的滚动接触疲劳方式,对高结合强度的硬质薄膜进行评价,并采用有限元方法计算弹塑性变形条件下的应力分布,切应力幅的计算结果具有合理性。改进后的滚动接触疲劳法允许基体发生弹塑性变形,界面切应力大幅度提高,能够在相对较少周次下造成薄膜剥落,失效部位发生于界面,因而更适合于评价结合强度较高的硬质薄膜。A novel technique was developedto measure the adhesion at hard coatings/substrate interface by modify- ing the conventional rolling contact fatigue method. The modification included the small AI203 ball with high elastic modu- lus and the stress calculation in finite element method （FEM）, based on the elastic-plastic deformation, instead of in Hertzian theory. Since the modifiedteehnique allows plastic deformation in the substrate, it significantly widens the shear stress range at the interface.The interfaeial adhesions of hard coatings （Mo2N and TiN） and substrate of M2 high-speed steel were evaluated in the conventional and new techniques. The measured results show that the small scraps of elastic hard coatings could be peeled off by delamination from the plastically deformed substrate for fewer cycles of adhesive fail- ure, and that the results evaluated in the conventional and new techniqueswere in good agreement. We suggest that the novel technique be of much technological interest in quantitative interracial adhesion assessment for thin hard films.

关 键 词：硬质薄膜 结合强度 滚动接触疲劳 有限元 弹塑性 

分 类 号：TG174.4[金属学及工艺—金属表面处理]