Tribological study of magnesium-based AZ91/TiC/rGO hybrid composite prepared by powder metallurgy route: an experimental and analytical approach

In this research, hybrid composites of magnesium alloy (AZ91) reinforced with titanium carbide (TiC) and reduced graphene oxide (rGO) were studied. The powder metallurgy method was used to synthesise magnesium alloy-based hybrid composites. The tribological behaviour of fabricated composite samples was examined using a pin-on-disc tribotester per the ASTM G99 standard. Using the Taguchi method, the design of the experiment (DOE) was constructed. The L9 orthogonal array opted for tribo-performance evaluation. Also, an ANOVA and regression analysis were carried out to ascertain the relative impact of the tribological factors on the responses. In the present investigation, three variable factors were considered, i.e. reinforcement percentage of TiC (0–10%) keeping constant 0.5 wt.% rGO, disc sliding velocity (0.5 to 1.5 m/s), and applied load varies between 10 and 30 N. It was found that the load parameter had a considerable impact on both the wear rate (WR) and the coefficient of friction (COF). Sliding velocity, on the other hand, had a minimal effect on WR. The concentration of reinforcement exhibits a moderate effect. Taguchi's predictive results were also compared with experimental results. The worn surfaces were analysed using scanning electron microscopy (SEM), and surface roughness was used for wear mechanics analysis.