Structure and abrasive wear resistance of R6M5 steel-tungsten carbide composite coatings

Features of the structure formation, composition, and abrasive wear resistance of R6M5 steel-tungsten carbide (R6M5-WC) composite coatings have been studied as dependent on the WC content. The introduction of ～20 wt % WC into the hardening composition leads to an increase in the fraction of M₆C carbide (in the form of eutectic inclusions with average size ～5.9 μm at grain boundaries and dispersed ～0.25 μm particles in the volume of grains), while a large proportion of metastable austenite (～88 vol %) is still retained. The R6M5-WC coatings exhibit high abrasive wear resistance, which is ensured by the γ → α′ martensite transformation during friction and a muiltimodal size distribution of hardening particles.