Abrasive wear behaviour of SiCp/Al alloy composite in comparison with ausferritic ductile iron

Abstract

Abstract The abrasive wear behaviour of SiCp/Al composites (MMCs) prepared by liquid metallurgy method was investigated to find out effects of applied load and weight fraction on a pin-on-disc configuration. The MMC pins containing 20 wt.% particles with sizes of 50 μm and its 2014 Al alloy were tested under different conditions against SiC abrasives. The wear performances of MMCs were also compared with those of ductile iron (DI), partially austenitized and austempered ductile iron (PADI) and conventionally austenitized (full austenitized) and austempered ductile iron (CADI) under similar conditions. Moreover, wear surfaces of tested samples were examined in a scanning electron microscope (SEM). Hardness, density and porosity increased with increasing wt.% of particle for the composite, but for the PADI and CADI sample, hardness increased with increasing martensite volume fraction and ausferrite volume fraction. The experimental results showed that wear rate of the composite decreased slightly with increasing SiCp contents and increased with increasing load. The wear resistance of MMCs was found to be better then those of DI, PADI and CADI materials, when tested against 70 μm sizes of abrasives. Furthermore, SEM examination showed that a few wear craters, combined with re-attachment of debris particles, was dominant for the composite, but the fragmented debris particles, when tested at lower loads, were found the more dominant for MMCs. Adhesion, chipping and abrasion were responsible mechanisms for the alloy, but abrasion was the most effective mechanism for the CADI samples.