The wear behavior of (Ti, W, Mo, Cr) (C, N)-based cermet under a wide load range

Abstract

The solid solution carbonitride -based cermet such as (Ti, M)(C, N)-based cermet (M represents transition metals) with low mismatch interfaces, hold significant potential to application in molds, cutting tools, and other wear-resistant parts. However, their wear behavior and mechanisms under reciprocating sliding contact and wide load range remain unclear. Herein, we investigate the unlubricated tribological behavior and wear mechanisms of (Ti, W, Mo, Cr)(C, N)-based cermet at a wide load range from 5 N to 100 N. Under low load, (Ti, M)(C, N)-based cermet exhibits excellent wear resistance compared to traditional Ti(C, N)-based cermet. The low friction coefficient and wear rate are attributed to the synergistic effects of transition metal oxides, particularly the self-lubricating properties of molybdenum trioxide (MoO₃). Under high loads, the wear mechanism changes from the formation and failure of oxide layers, to accelerated abrasive wear and subsequently to an extremely slow wear caused by the Al-rich adhesive layer generated from elemental transformation between the tribo-couples. Furthermore, the strong interfacial bonding helps prevent crack growth between the core and rim phases. This study provides a theoretical basis and guidance for further improving the wear resistance of (Ti, M)(C, N)-based cermets and expending their potential application domains.