Investigation of the role of oxide scale on Stellite 21 modified with yttrium in resisting wear at elevated temperatures

The research demonstrated that a stronger and more adherent oxide scale could markedly benefit the wear resistance of Stellite 21, leading to lower wear of the alloy in air than in the argon environment. An improved oxide scale by yttrium rendered the oxide scale more protective. However, the protective effect of oxide scale decreased under high wearing forces.