Wear resistance of nanostructured Cr-based WC hardmetals sintered by spark plasma sintering

Nanostructured Cr-based WC hardmetals are successfully sintered by spark plasma sintering. The wear behaviour
of these Cr-based WC hardmetals with different C contents ranging from 5.57 wt% to 6.91 wt%, is evaluated
performing sliding wear tests under two different wear conditions. This work analyses the influence of the
C content on the wear performance through the study of the phase formation and WC grain size. The Cr-based
hardmetal with 5.57 wt% C content exhibits a lower wear rate than Co-based WC hardmetals tested under
similar dry ball-on-plate wear conditions, even considering that these Co-based WC hardmetals have higher WC
content (90 wt%) than Cr-based WC hardmetals (83.2 wt%). The combination of a nanosized WC grain and the
avoidance of brittle (Cr,Fe)7C3 or soft graphite phases leads to a superior wear performance. Thus, the use of Crbased
binders in the hardmetal industry, alternatively to Co-based binders, is promising in applications in which
high wear resistance is needed.