Effect of Mo and Ag on the friction and wear behavior of ZrO2 (Y2O3)–Ag–CaF2–Mo composites from 20 °C to 1000 °C

• ZrO2 (Y2O3)–10Ag–10CaF2–10Mo show good wear rates from 20 °C to 1000 °C.
• The effect of Mo on the friction and wear behavior of ZrO2 (Y2O3) was studied.
• CaMoO4 provide lubrication at high-temperatures.

In this paper, a series of ZrO2 matrix high-temperature self-lubricating composites were prepared by hot-press technique. The effect of Mo and Ag on the friction and wear behavior of the ZrO2(Y2O3)–Ag–CaF2–Mo composites in a wide temperature range was investigated. The XRD results showed that CaMoO4 formed on the worn surface above 400 °C. The excellent lubrication performance of CaMoO4 endowed the low coefficient of friction of the ZrO2(Y2O3)–Ag–CaF2–Mo composites at high temperatures. The ZrO2(Y2O3)–10Ag–10CaF2–10Mo composites showed favorable wear resistance at all the tested temperatures which was attributed to the combined action of hardness and phase transformation.