Modeling the Formation of Thermal Spray Coatings on a Rough Substrate

Abstract Thermal spray coatings are typically applied to grit-blasted, rough surfaces, though coating models generally assume smooth substrates. This research involved simulating nickel coating formation on rough stainless-steel substrates in an atmospheric plasma spray process. The researchers evaluated coating topography, porosity, thickness, and roughness using a Monte-Carlo stochastic algorithm. The temperature differential between coating and substrate creates residual thermal stresses, which were analyzed using NIST's Object Oriented Finite element software (OOF). Results indicate that substrate roughness increases coating roughness and creates non-uniform stress distribution with concentration points at the coating-substrate interface.