H. T. Koivuluoto, J. Lagerbom, P. Vuoristo, Tampere University of Technology, Tampere, Finland
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 coatings, and especially to study the effects of powders, substrates, and also heat treatments to the adhesion strength. The adhesion strengths were measured with pull test. The coating materials were copper and nickel chromium alloys. Three different copper powders and four 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 adhesion strength improved during heat treatments because of ductilization and softening, even at quite low annealing temperatures.
Summary: The aim of this study was to investigate the adhesion strength of cold sprayed coatings, and especially to study the effects of powders, substrates, and also heat treatments to the adhesion strength. The adhesion strengths were measured with pull test. The coating materials were copper and nickel chromium alloys.