EVALUATION FOR ADHESION STRENGTH OF HARD COATINGS BY WEDGED LOAD TEST METHOD

摘要

A wedged load test method was used to evaluate the adhesion strength of hard coatings. In this test, a wedge indenter was put in a wedge-shaped groove on the sample surface and the midline of the indenter superposed with the interface of the substrate exactly. Then static load was exerted until the coating fractured along the interface. Based on the critical forced condition, an equation for the adhesion strength of the coating and substrate was presented, so that the adhesion strength of samples with three kinds of different hard coatings were determined. The results show that the wedged load test method can be used to evaluate the adhesion strength of hard coating and substrate. The disparity of experimental data consist with the ASTMC663-79 Standard. The results were not influenced by non-stochastic factors.