抄録
Cold spraying is a promising process to fabricate functional coatings. In conventional thermal spraying, feedstock powder materials require molten or semi-molten state, especially in high temperature plasma and flame spraying technique, during deposition onto the substrate. On contrary, cold spraying is a technique where the particles are deposited in a solid state without changing the physical and chemical nature of the spray powder. It enables to fabricate high quality coatings. Because of the solid state particle deposition, the electrical and chemical properties of the cold-sprayed coatings are similar to the bulk materials. On the other hand, the mechanical properties, such as coating strength, differ from the bulk one due to the severe plastic deformation of the particles. The residual stress can be considered to be the main reason for this difference. In this study, the effect of heat treatment on the mechanical properties of the coatings was carefully investigated to clarify the influence of residual stress. The mechanical properties were examined as shear adhesion strength test and bending test for adhesion and cohesion strength evaluation, respectively. These measurement results indicated that the residual stress affect these strength significantly.
