Abstract
In cold spraying, various issues affect the mechanical properties of the coatings. Adhesion strength is usually considered to be the most crucial mechanical property. The aim of this study was to investigate the adhesion strength of cold sprayed copper and nickel chromium alloy coatings. The focus was especially in studying the influence of powders, substrates and heat treatments on adhesion strength. Three different copper and three nickel-20%chromium powders were tested. The substrate materials were carbon steel and copper. Furthermore, effect of substrate pre-treatment to the adhesion strength of the cold sprayed copper coatings was investigated. The influences of the powders and the substrates on the cold sprayed coatings were dependent on the materials. Adhesion strength of the cold sprayed Cu coatings was significantly higher on the Cu substrate than on the steel substrate. Moreover, heat treatment improved the adhesion strengths with increasing annealing temperature.