Recent developments and potential applications of cold spraying

Whereas coating formation in thermal spraying is related to complete or partial melting of the feedstock material, bonding in cold spraying occurs only due to the high kinetic energy upon particle impact. Thus, undesired thermal effects on the spray material can be avoided, making the method suitable to retain properties of the feedstock powder in cold sprayed coatings and unlocking new potentials for metal powder spraying. Since bonding occurs by high velocity impacts of solid particles, the description of bonding requests new concepts, which have to be linked to conditions to reach maximum acceleration. The evaluation of such concepts supplies more general tools to predict necessary requirements for cold spraying of metallic materials and to tune optimum spray conditions.