Mechanical characterization and frictional wear behavior analysis on nano tungsten carbide and molybdenum disulfide particles reinforced aluminium 7075 composites

Abstract

Hybrid metal matrix composites are gaining more importance in recent years. In this current investigation, aluminium alloy (AA7075) composites have been prepared with nano tungsten carbide (WC) and molybdenum disulfide (MoS₂) as reinforcements using stir casting method and investigated. The nano tungsten carbide particles were added into the matrix in the proportions 0%, 0.5%, 1%, 1.5% and 2%, and molybdenum disulfide was added in the constant proportion of 5 wt.% to the molten metal. The prepared Al-hybrid composite samples were tested for their hardness, compression and tensile strength. Microstructure examination has also been performed to understand the distribution pattern of nano tungsten carbide and molybdenum disulfide particles in the base matrix by scanning electron microscope. From the results, it was found that there was steady improvement in composite properties when compared with the base metal while adding WC and MoS₂. Thus, the prepared AA7075/MoS₂/WC composites were guaranteed for high strength, hardness and exceptional microstructure stability. Dry sliding wear behavior on AA7075/MoS₂/WC composites was investigated with the aid of pin-on-disc apparatus. Grey Relational Analysis tool was employed to identify the optimal setting of process variables, which results in lower wear rate and COF. The significance of factors such as sliding distance, sliding velocity and load on the wear characteristics was investigated by means of ANOVA. ANOVA results unveiled that load was the majorly influencing factor in attaining optimal wear characteristics. The tested samples have been investigated using scanning electron microscopy and reported.