H. T. Mäkinen, J. Lagerbom, P. Vuoristo, Tampere University of Technology, Tampere, Finland
Cold spraying is quite a new process, which is an effective method to deposit dense and pure coatings. The aim of this study was to investigate microstructures and mechanical properties (hardness and adhesion) of the cold sprayed coatings. The coating materials were copper, aluminum, nickel, zinc and tantalum. The substrate materials were carbon steel and copper. Influence of heat treatment on mechanical properties was studied, especially different heat treatment times and temperatures. The hardness of the cold sprayed coatings was higher than thermally sprayed coatings and bulk materials. After heat treatment the hardness of the cold sprayed coatings decreased and the ductility increased. Corrosion resistance of the cold sprayed coatings were also studied. The corrosion resistance was tested with salt spray (fog) testing and open cell potential measurements. The corrosion tests showed some open porosity but some parts of the cold sprayed coatings appeared to be fully dense, which showed their potential to corrosion protection.
Summary: SUMMARY
Microstructures and mechanical properties of as-sprayed and heat-treated coatings prepared by cold spraying were investigated. The coating materials were copper, aluminum, nickel and zinc. Corrosion resistance of the coatings was also studied by salt spray testing and open cell potential measurements.
ABSTRACT
Cold spraying is quite a new process, which is an effective method to deposit dense and pure coatings. The aim of this study was to investigate microstructures and mechanical properties (hardness and adhesion) of the cold sprayed coatings. The coating materials were aluminium, copper, nickel and zinc. The substrate materials were carbon steel and copper. Influence of heat treatments on mechanical properties was studied, especially different heat treatment times and temperatures. The hardness of the cold sprayed coatings was higher than that thermally sprayed coatings and bulk materials. During heat treatment, the hardness of the cold sprayed coatings decreased and the ductility increased. Corrosion resistance of cold sprayed coatings was also studied. The corrosion resistance was tested with salt spray (fog) testing and open cell potential measurements. The corrosion tests showed some through-porosity but some parts of the cold sprayed coatings appeared to be fully dense, which showed their potential for corrosion protection.
