The effects of heat treatment on the mechanical properties of cold-sprayed coatings

• Measured the mechanical properties of several typical cold-sprayed coatings.
• Discussed the improvement of coatings' properties via heat treatment.
• Clarified the importance of coating's densification, and it influences the mechanical properties.

In the cold spray process, deposition of particles takes place through intensive plastic deformation upon impact in a solid state at temperatures well below their melting point. Therefore, spray particles experience little oxidation or decomposition during this process. As a result, cold-sprayed coatings have excellent mechanical, electrical and thermal properties. In this work, pure Al, Cu, Ti and stainless steel 316 were deposited by cold spray. The tensile strength and elongation of these coatings were also measured. The results showed that the as-sprayed coatings of the four materials have poor ductility and almost no elongation. However, heat treatment can improve the mechanical properties of the cold-sprayed coatings to some extent. Here, the effects of heat treatment conditions on the mechanical properties of the four cold-sprayed materials are discussed.