High-temperature tribological behavior of ZrO2–MoS2–CaF2 self-lubricating composites

It is of great significance to find ways to control the high-temperature friction and wear of ceramic materials. In this paper, a ZrO2 matrix high temperature self-lubricating composite with addition of MoS2 and CaF2 as lubricants were prepared using hot pressing method by tailoring the composition of CaF2. The wear and friction behavior of the composites was investigated from room temperature to 1000 °C. The ZrO2–MoS2–CaF2 composites against SiC ceramic exhibited excellent self-lubricating and anti-wear properties at a wide temperature range. At 1000 °C, the ZrO2–10MoS2–10CaF2 (wt.%) composite has a very low coefficient of friction of about 0.27 and wear rate of 1.54 × 10−5 mm3/(N m). The low friction and wear were attributed to a new lubricant CaMoO4 which formed on the worn surfaces at high temperatures.