Optimization of wear and friction behaviour of AZ91D –B₄C − Gr hybrid composite under dry sliding conditions

The tribological behaviour of AZ91D magnesium alloy bottom pouring stir cast with boron carbide (B4C) and graphite (Gr) was examined. The wear and frictional properties of AZ91D magnesium alloy, AZ91D-B4C composite, and AZ91D-B4C-Gr hybrid composite were investigated individually under dry sliding circumstances. To perform the studies, the L9 orthogonal array approach was adopted to investigate the effects of various sliding distances (0.5, 1, and 2 km) and applied load (5, 10 and 20N). When compared to AZ91D magnesium alloy and AZ91D- B4C composite, the wear loss for the AZ91D- B4C-Gr hybrid composite were reduced by 52.2% and 17.76% respectively at maximum load (20N) and sliding distance (2 km). Compared to AZ91D magnesium alloy, the hybrid composite had a higher hardness. SEM analysis of worn surfaces was performed to determine the significant abrasive wear process. The critical factors affecting the wear losses were generated using analysis of variance (ANOVA).