| Abstract Scope |
In this presentation, the sliding wear behavior of two magnesium alloys, namely AM100 and ZC63, and their saffil alumina short fiber-reinforced composites produced by the technique of squeeze infiltration will be elegantly highlighted and lucidly detailed. The sliding wear tests were conducted on two different types of counter-face materials, namely: EN24 Steel and SiC abrasive discs, using a pin-on-disc tribometer. The test results revealed that against both the chosen types of discs, the magnesium alloy-based composites revealed enhanced resistance to wear when compared to the unreinforced counterpart. It was observed in the two chosen composite systems that: (i) against EN24 steel disc, the wear rate decreased with an increase in volume fraction of the fiber reinforcement, and (ii) against SiC abrasive disc, the wear rate increased with an increase in volume fraction of the fiber reinforcement. Further, the ZC63 and its composites revealed noticeably higher wear rates than the AM100 composites when slid against a silicon carbide (SiC) counter-face. Such a behavior shown by the ZC63 system can be ascribed to the influence of the wear debris, as a third body, on the overall wear process. The nature of matrix (ductile or brittle) played an important role in determining the wear behavior of the chosen ZC63 and AM100 composites. The ZC63 matrix was ductile and the resultant debris arising from the ductile matrix was observed to be both embedded and compacted in the abrasive grits of the SiC counter face along with the hard alumina fibers. The compacted material on the counter-face disc caused counter-abrasion of the ZC63 composite test pin resulting is a higher wear rate on repeated sliding. For the AM100 composites, the matrix was brittle due to presence of Mg17Al12 precipitates. Unlike in the case of ZC63 composites, the wear debris generated from the brittle matrix remained free without getting compacted in the abrasive grits of the SiC counter-face, thereby minimizing counter-abrasion resulting in an observably lower wear rate. |