TRIBOLOGICAL ANALYSIS OF INNOVATIVE HYBRID Al-SiC-ZrO₂ METAL MATRIX COMPOSITES FABRICATED USING POWDER METALLURGY ROUTE FOR AUTOMOTIVE APPLICATIONS

Extensive research in materials science is needed to address the global paucity of natural (or monolithic) materials. Aluminum (Al) based hybrid metal matrix composites (HMMCs) are ideal for automotive engineering and medical applications due to their lightweight, high stiffness, hardness, and wear resistance. Wear characteristics of such composites are evaluated by a tribology study. In the present work, Al-based hybrid MMCs with silicon carbide (SiC) and zirconium oxide (ZrO₂) reinforcing particles have been developed via powder metallurgy. A total of 25 different types of MMCs were fabricated using the Taguchi robust technique. Tribology investigation with evaluation of the coefficient of friction (COF) using a pin-on-disc tribometer at a load of 10 N and a sliding time of 50 minutes has been carried out. The fabricated hybrid Al MMCs containing 7 wt.% SiC and 14 wt.% ZrO₂ particles exhibited the lowest COF during the wear test. The greatest and lowest microhardness and COF values obtained among all fabricated hybrid MMCs are (86.6 HVN and 30.6 HVN) and (0.8403 and 0.4518), respectively. The scanning electron microscopic investigation confirmed the improved wear characteristic of the developed MMCs, suitable for engine block pistons, piston insert rings, and brake rotors of automobiles.