MODELING OF FAILURE FEATURES FOR TiN COATINGS WITH DIFFERENT SUBSTRATE MATERIALS

Abstract

A set of continuum viscoplastic damage constitutive equations is presented in this paper. The equations are calibrated for a TiN coating material, and a number of substrate materials, and are implemented into the commercial finite element (FE) solver, ABAQUS, through the user-defined material subroutine, VUMAT, for FE simulation. An FE model has been created to simulate a load-bearing test. Studies are carried out to investigate failure features of the coating with variations in coating thickness for three different substrate materials: pure copper, a gear steel and a tool steel. It has been demonstrated that the proposed damage equations can be used to predict failure features of coatings, which are affected by the thickness of the coating and the stiffness of the substrate.