Restoration of face-centered cubic metals subjected to kinetic spraying

Deformation mode and restoration of face-centered cubic (FCC) metal (Al, Ni, and Cu) particles subjected to kinetic spraying (KS) were investigated. The FCC metal particles were accelerated to supersonic velocity by high pressure process gas, and collided with substrates or previously deposited coating layer. The high velocity impact of in-flight particles and their successive deposition leads to severe plastic deformation at ultra-high strain rate and the dissipation of heat energy from the plasticity. Accordingly, highly strained interface undergoes restoration to stabilize strained area during KS. Although Al, Ni, and Cu have equivalent slip systems {111} 〈110〉, the different physical and metallurgical properties of the FCC metals differentiate the deformation mode and lead to variations in static recovery and recrystallization rates. The deformation and restoration behavior of KS FCC metals are discussed, taking into account the physical and metallurgical factors such as stacking fault energy, dislocation mobility, diffusivity, and melting point.