涂层剥离的内聚力-离散化虚内键模型与数值模拟  

Modeling of Coating Peeling by Cohesive Discretized Virtual Internal Bonds and Numerical Simulation

作　　者：李玲玲 张振南[1] 郭芳威 LI Lingling;ZHANG Zhennan;GUO Fangwei(School of Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学船舶海洋与建筑工程学院,上海200240 [2]上海交通大学材料科学与工程学院上海市先进高温材料与精密成形重点实验室,上海200240

出　　处：《表面技术》2025年第7期203-211,共9页Surface Technology

基　　金：上海交通大学深蓝计划(SL2022MS013)。

摘　　要：目的涂层剥离涉及大位移大变形问题。为了更好地模拟涂层剥离过程,提出了内聚力界面-离散化虚内键(DVIB)方法。通过数值模拟,研究了涂层和界面特性以及界面裂纹对涂层剥离的影响。方法在模拟中,涂层和基体之间的界面特性通过双线性黏结法则(Cohesive Law)来描述。涂层看作由离散键元胞组成,每个键元胞由有限条虚内键组成。键元胞的“节点力-位移”关系直接由键势函数(Bond Potential)导出,没有引入任何连续介质假设,因此DVIB可以直接模拟涂层大位移和大变形问题。结果采用该方法对不同条件下的涂层剥离进行数值模拟,分析不同条件对涂层剥离的影响。涂层厚度和模量影响稳定阶段之前的剥离力,涂层黏附能影响整个过程剥离力。涂层厚度、模量和界面黏附能都与涂层剥离力呈正相关;涂层与基体之间的端部裂纹会使涂层峰值剥离力减小;内部裂纹长度和位置均会对剥离力产生不同的影响。当黏结强度和界面黏附能一定时,黏结法则的几何形状只会影响剥离力的峰前段,对剥离力的峰值和峰后阶段几乎没有影响。结论本研究为涂层剥离提供了一种新的模拟方法,研究结果为涂层剥离分析提供有意义的借鉴。As a barrier structure,the coating plays important roles to prevent the material from damage,corrosion,etc.However,the way to effectively model and simulate the coating peeling behaviors is still a tough but important problem since it involves large deformation and large displacement.Moreover,the coating peeling mechanism and its influence factors are still not well understood.To better simulate and get a deeper insight into the coating peeling behaviors,the cohesive interface-discretized virtual internal bond method(DVIB)is developed in this paper.Through the numerical simulation,the impact of the coating properties,the interface properties,the interface crack and the shape of cohesive law on the coating peeling behaviors are studied in detail.The coating/substrate system consists of three components:the coating,the interface,and the substrate.In the present method,the adhesion of the coating to the substrate is characterized by a bilinear cohesive law based on the hypothesis of a smooth substrate surface.For the rough substrate surface case,equivalent adhesion energy for the coating is proposed to deal with this problem.The coating is considered to consist of bond cells.Each bond cell has a finite number of bonds.The nodal force-displacement relation of a bond cell is directly derived by a bond potential,without any continuous hypothesis.Thus,DVIB can directly simulate the large deformation and large displacement behaviors of the coating.Through this method,the coating peeling processes under different conditions are simulated and the influence factors on the peeling behaviors are analyzed.The thickness,modulus,and interfacial adhesion energy of the coating significantly affect the peeling force and the damage zone length.The coating modulus mainly affects the peak peeling force rather than the steady one.The higher the modulus is,the higher the peak peeling force.The thickness of the coating has a similar effect on the peeling force.This is because both the higher modulus and the thickness can lead to a strong

关 键 词：涂层剥离 离散虚内键 界面 黏结法则 数值模拟 裂纹 

分 类 号：TG174.4[金属学及工艺—金属表面处理]