Study on the oxidation behaviours and the interactions between friction and oxidation of the Ni-based composites with in-situ carbides reinforcement at 800 ℃

Oxidation behaviours and the interactions between friction and oxidation of Ni-based composites with in-situ carbides reinforcement were investigated at 800 ℃. Oxidation kinetics obey parabolic and parabolic-linear law. Oxide layers present hierarchy with three sublayers. I and II sublayers contain NiO, TiO2 and NiTiO3 etc.; III sublayer is O embrittled alloy layer. The pores in oxide layer result to transformation of oxidation kinetics from parabolic law to linear law. The worn oxide layers show the similar three-layered structure, comparable composition and faster thickening. Ultra-high flash temperature on worn surface induced by friction accounts for the formation and development of oxide layer.