Cold-sprayed coatings: Microstructure, mechanical properties, and wear behaviour

Deposition of coatings on the surface of a bulk material is a versatile, economical, and effective strategy to provide additional features to the bulk material, mainly to improve its functionality and extend its service life. Among all the thermal deposition techniques, cold spray (CS) is the only technique in which particles are deposited below their melting point, and therefore, it is a solid-state processing technique. Coatings generated via CS exhibit different characteristics from those of the coatings produced by other methods; this may make CS a competitive technique for the repair and even for the manufacture of self-standing components. This study presents a basic description of CS and a review of its applications in the deposition of metallic coatings, specifically those based on materials such as Al- and Ti-based alloys, used in aeronautical components. CS is a thermal spray technique that enables the production of coatings with properties and behaviours similar to those of bulk materials with similar compositions.