Influence of WC addition on wear resistance of Fe-Mn-Si-Cr-Ni alloy by laser additive manufacturing

Fe-17Mn-6Si-9Cr-5Ni alloy with varying WC concentrations was fabricated via laser wire deposition additive manufacturing. Their tribological performance under oil-lubricated conditions was systematically evaluated to elucidate the influence of WC addition amount on the wear resistance of Fe-Mn-Si-Cr-Ni alloy. Results demonstrate that in the Fe-Mn-Si-Cr-Ni alloy, when the WC addition amount does not exceed 1% (by mass fraction), the hardness of the alloy increases with the increase in WC addition amount, but its wear resistance actually decreases. At this point, the wear resistance of the alloy is mainly influenced by the intrinsic friction-reducing and wear-resistant properties brought about by the stress-induced martensitic phase transformation in the iron-based memory alloy. However, when the WC addition amount is increased to 2% and 4%, the hardness of the alloy continues to increase with the increase in WC addition amount, and its wear resistance improves accordingly, which is still only approximately the same as when no additives are added. At this point, martensite laths can no longer be observed in the sub-surface layer of the friction wear. It can be considered that at this point, the wear resistance of the alloy is mainly influenced by the dispersion strengthening effect of the WC particles. Under the conditions studied in this paper, the alloy with 0.25% WC added has the best wear resistance.