Abstract
The fact that metal matrix is incompatible with hexagonal boron nitride (h-BN) seriously aggravates the me-chanical and tribological properties of solid-lubricating composites. This study successfully introduces a solid -lubricant h-BN@Ag (Ag nano powders generated in-situ on h-BN surface). Adding h-BN@Ag to CoCrNi me-dium entropy alloys significantly improve the fracture toughness of the CoCrNi/h-BN (increased by 40.1%), which is resulted from decreasing porosity of the composite. In comparison with the CoCrNi/h-BN composite, obvious plasticity characteristics are found in CoCrNi/h-BN@Ag composite. Moreover, the composite containing h-BN@Ag exhibits a low, stable coefficient of friction (COF) in a wide temperature range (RT-600 degrees C). Obvi-ously, the COF of CoCrNi/h-BN@Ag composite is more stable than CoCrNi/Ag composite. Our findings show that adding h-BN@Ag is an effective way to enhance the fracture toughness and tribologicial behaviors of the CoCrNi matrix composites.

Keywords Plus:FRICTIONWEAR

Published in MATERIALS LETTERS,Volume344;10.1016/j.matlet.2023.134398,AUG 1 2023