Abstract
Cold spraying is a promising process to fabricate functional coatings. Because of the solid state particle deposition, the electrical and chemical properties of the cold-sprayed coatings are almost similar to the bulk materials. The most important factor to deposit a particle through cold spraying is known as the critical velocity. When the particle velocity is beyond the critical velocity, the plastic deformation of both sprayed metallic particle and metallic substrate cause the removal of surface oxide layers and newly-formed surfaces are explored. The newly-formed surface yields the metallic bond, and then the cold spray deposition can be obtained. Therefore, the substrate conditions also must be considered to understand the cold spray process. In this study, the influence of substrate roughness on adhesion strength of coatings was investigated by grit blasting. The adhesion strength was examined by a shear adhesion test. The shear adhesion test showed that the grit blasting enhances the adhesion strength. As the causes of these, an anchor effect was suggested.
