Influence of Cold Gas Spray process conditions on the microstructure of Fe-based amorphous coatings

Fe-based amorphous metallic coatings were prepared by Cold Gas Spray process. Through this study, the effects of the process conditions such as spraying distance, gas pressure and temperature on the microstructure of as-sprayed coatings are evaluated. Microstructural studies show that the coatings can present a densely layered structure with porosity below 0.5% and thickness around 800 mu m depending on the process conditions. Precipitation of nanocrystals in as-sprayed coatings is observed and present results show its dependence on the thermal and kinetic energy implicated in the process. In general, when gas temperature and pressure decreased, in the studied range, coatings displayed a dense and amorphous structure. (C) 2014 Elsevier B.V. All rights reserved.