Evaluation of Fracture Toughness and Crack Propagation of Aluminum Alloy 7075-T651 with Chromium Oxide Coating

Abstract

Fatigue crack formation is the most important factor affecting the damage in parts under subjected to the repeated stresses. In this context, intensive researches are continuing on the protective hard coatings in the aviation and automotive sectors in order to increase the fatigue life especially in aluminum alloy parts. Chromium oxide (Cr2O3) based coatings are widely used in many industrial applications due to high corrosion resistance, high hardness and high surface resistance. In this study, fatigue crack propagation on 7075-T651 alloy with chromium oxide coating by thermal spraying method was investigated. Test results show that the crack propagation is slowed down by the chromium oxide based coating and increase the surface resistance of the aluminum alloy.