Application of a new quantitative evaluation technique for the strength of PVD coatings

Abstract

Mechanical strength of a thin film deposited on a substrate should be characterized by basically four parameters, which are strength of the film, strength of the interface, Young's modulus of the film and residual stress in the film, provided that properties of the substrate are given. A systematic method of measurement for these parameters has recently been developed by the authors. In this study, variations of this method are newly developed in order to evaluate those parameters even in the case of brittle thin films with tough interface and large residual strain which the original method could not manage. The new technique is successfully applied to the case of wear resistant PVD coatings on cutting tools.