Structure, mechanical, and tribological properties of Ag2CrO4 high-temperature oxide coatings

In this research, a series of Ag2CrO4 high-temperature self-lubricating oxide coatings were prepared by reactive radio frequency magnetron sputtering under different argon-oxygen flow ratio (Ar:O2 ratio) conditions. Effects of the gas flow ratio on phase composition, coating morphology, high temperature treatment in air atmosphere, mechanical and tribological properties are studied. A low Ar:O2 flow ratio is beneficial for the formation of Ag2CrO4 phase. At high temperature treatment, formation of surface Ag particle and volatility and decomposition of the Ag2CrO4 phase are observed, and the volatility and decomposition of the coating are slight at temperatures below 500 °C. When the Ar:O2 ratio is 1:1, the coating shows exceptional comprehensive performance, it is dense with a smooth surface, excellent toughness and bond strength, and the lowest wear rate and coefficient of friction, which is 0.14 mm3/10−3N∙m and 0.35 respectively. The coating can function as a lubricant in temperature environments of 500 ℃ and below, demonstrating practical application value.