Effect of Pre-Oxidation on a Ti PVD Coated Ferritic Steel Substrate during High-Temperature Aging

A PVD coating is often applied on the surface of metallic alloys to improve their high-temperature resistance. In present work, a thin titanium layer (1.2 µm) was deposited by stainless steel substrate before exposure (800 °C in ambient air). The underlying idea that Ti converts into oxide (TiO2) during aging at 800 °C, thereby slowing down oxidation. stability with and without pre-oxidation investigated. Morphological, structural, chemical characterizations were performed completed simulation film growth measurement mechanical state substrate. case sample not pre-oxidized, oxidation slowed TiO2 scale but spallation observed. On other hand, when provided more significant protection against oxidation, spalling or cracking did occur. combination different kinds stress could explain two behaviors, namely, growing stress, thermal occurring cooling down.