Abstract
In this study, stainless steel splats were deposited on preheated stainless steel substrates with oxide scales of different thickness in inert low-pressure plasma spay (LPPS) conditions to examine the effect of in-situ oxidation of prior splats on the morphology and bonding of subsequently formed splats. Splat-substrate interface cross-sections were prepared by focus-ion-beam milling. Splat morphology and bonding state with the substrate were characterized by SEM. The results show that with oxide films up to 35 nm thick, disk-type splats are deposited that bond well to the substrate except in the periphery region. As oxide films become thicker (100 nm) and present a surface with micro-scale roughness, splats take on a finger-like shape with poor bonding at the interface.
