SELF-LUBRICATING WC/Y–TZP–AL2O3 HYBRID COMPOSITE WITH DISPERSED HADFIELD STEEL PARTICLES

10.25712/ASTU.1811-1416.2026.03.010

Abstract

Hybrid composites with a WC/Y–TZP–Al₂O₃ ceramic matrix and dispersed Hadfield steel particles were sintered and then tested at sliding velocities in the range of 7–37 m/s and a contact pressure of 5 MPa. The use of short-term (10 min) and low-temperature (1350 °C) sintering under pressure made it possible to obtain a composite consisting of micron-sized WC grains and submicron-sized ceramic grains of partially yttria-stabilized polycrystalline tetragonal zirconia and alumina (Y–TZP–Al₂ O₃) and uniformly distributed Hadfield steel grains. This microstructure provided new hybrid properties, combining high hardness (~14.8 GPa) and fracture toughness (~11 MPa×m^1/2) with effective tribochemical adaptation of the composite under high-speed sliding conditions on steel. The composites demonstrated a low coefficient of friction and high wear resistance due to the in-situ mechanochemical formation of iron tungstates FeWO4 and Fe2WO6 on the friction surfaces. These complex oxides were incorporated into the subsurface structures, providing self-lubrication and self-healing properties during high-speed sliding.