Cold spraying is a relatively new thermal spray process enabling the production of metallic and composite coatings with low porosity and low oxygen content. Such coatings are attractive for use in applications requiring, e.g., corrosion resistance and electrical conductivity. In the cold spray process, a coating is formed when powder particles in a solid state at high kinetic energy impact on the substrate surface, deform and adhere to substrate or other particles. The aim of this study was to characterize the structural properties of HPCS and LPCS coatings. Research focused on the microstructures and denseness of the coatings. SEM analysis and corrosion tests were taken to gain information on through-porosity. HPCS Ta, Ni, and Cu coatings showed a uniformly dense structure; however, HPCS NiCr and LPCS Cu+Al_2O_3 coatings contained through-porosity according to corrosion tests (electrochemical open-cell potential measurements). Furthermore, laser assistance was tested in order to evaluate an influence of laser energy on LPCS coating properties. LALPCS showed significant denseness improvement of the Cu+Al_2O_3 coating.
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