Nanometric WC-12 wt% AISI 304 powders obtained by high energy ball milling

Abstract WC cemented carbides with a greener alternative binder to Co, AISI 304 stainless steel (SS), were processed through high energy ball milling (HEBM). The milling parameters, such as rotation speed, ball-to-powder ratio and milling time were investigated. Selected milling conditions were applied to obtain a nanosized powder of WC-12 wt% SS with a highly uniform distribution of the ductile phase. For comparison, a conventionally wet milled powder was also prepared. Both powders were thermally characterized by dilatometry, up to 1450 °C, using vacuum atmosphere, and structural and microstructural analysis were performed in the sintered samples. The nanometric size of the HEBM powder particles markedly affected its densification and thermal reactivity; when compared with the micrometric powder obtained from conventional milling, early starting densification, with a greater contribution of solid state sintering, and increased reactivity, with formation of a larger amount of (M,W) 6 C phase, was noticed during sintering of HEBM powder compacts.