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 $\sim$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 $\sim$5.9 $\mu$m at grain boundaries and dispersed $\sim$0.25 $\mu$m particles in the volume of grains), while a large proportion of metastable austenite ($\sim$88 vol%) is still retained. The R6M5-WC coatings exhibit high abrasive wear resistance, which is ensured by the $\gamma\to\alpha'$ martensite transformation during friction and a muiltimodal size distribution of hardening particles.