Mechanical and Tribological Behavior of LM26/SiC/Ni-Gr Hybrid Composites

Abstract

The study evaluates the mechanical and wear properties of LM26 alloy and its hybrid composites with silicon carbide (SiC) and nickel-coated graphite (Ni-Gr). LM26 aluminum alloy is generally known for its high strength, wear, and corrosion resistance compared to similar materials such as zinc and magnesium. The effect of Ni-Gr was studied, with 2 wt.% was found to provide the best mechanical properties. LM26 composites reinforced with varying percentages of SiC (0 to 30 wt.%) showed the best properties at 20 wt.% reinforcement after fabrication using a bottom pouring type stir casting setup (Two step feeding method). Evaluation of five hybrid LM26 composites through tensile strength, elongation, hardness, impact, porosity, and thermal studies showed that the LM26/2 wt.% Ni-Gr/20 wt.% SiC configuration showed the best filler composition for improved strength. Sliding wear evaluation using experimental and Taguchi analysis was performed at different configurations to identify the best wear resistance. Microstructure studies showed the presence of Ni-Gr particles forming coatings and temperature playing a significant role in the progression of the wear rate. Furthermore, the hybrid composite with 20% SiC and 2% Ni-Gr reinforcement showed the best wear resistance.