A finite element model to include interfacial roughness into simulations of micromechanical tests

The presented finite element model uses a special arrangement of contact el ements to simulate surface roughness. Rough surfaces are described by three parameters: average roughness height, correlation length and coefficient o f friction. The standard programme ANSYS(R) is used to perform the calculat ions. Results of a finite element simulated Microbond Test using the fracture mec hanics approach for crack propagation and the presented model for interfaci al friction are shown as an example. The pull-out after complete debonding is also simulated. The influence of the surface parameters mentioned above on simulated load vs. displacement curves is studied, especially their effe ct on the stability of crack propagation and the interactions between the s urface parameters (frictional coefficient, roughness height) and interface parameters (critical stress intensity factors for crack propagation). (C) 1 999 Elsevier Science B.V. All rights reserved.