Tribological performances of CoCrFeNiAl high entropy alloy matrix solid-lubricating composites over a wide temperature range

The reliable operation of advanced industrial tribo-systems depends on solid-lubricating composites with excellent tribological performances over a wide temperature range. Here, we introduce the CoCrFeNiAl high-entropy alloy matrix solid-lubricating composites that exhibit outstanding wear-resistant and friction-reduced properties at temperature from room temperature to 800 degrees C. The formation of lamellar h-BN and Ag tribo-film inhibits the three-body abrasion and oxidative wear of the frictional interface below 600 degrees C, so that both the coefficient of friction and the wear of the composites are low. At 600 degrees C, high temperature softening of the composites increases its wear. At 800 degrees C, a protective oxide layer form on the worn surface of the composites, contributing to the low wear.