Development of Super Stainless Steel Coating with Improved Corrosion Resistance and Enhanced Hardness Focusing on Characteristics of Atmosphere Plasma Spray Process

As it is known atmosphere plasma spraying (APS) is a complex process, involving heating, melting and rapid solidification. Many studies related to preventing metallic oxidation in the melting state of particles by development and optimization of thermal spray process in order to maintain properties of spraying material, such as corrosion resistance of a stainless coating. In this study, an approach has been adopted to reduce oxide content by developing specific feedstock powders. Addition of Si,B,C to thermal spray feedstock is concerns relating to the characteristics of the APS process, one is to suppress oxide formation in the in-flight particles and another one is to form ultra fine-grained carbides and borides through the rapid solidification. Increasing B and C to 3% and further with adding Ti, Nb and V to feedstock alloy powder with a composition equivalent to SUS836L, successfully improved corrosion resistance and increased vicks hardness of APS sprayed alloy coating.