Assessment of tribological characteristics of stir cum Squeeze cast AlSi7Mg with 3wt % MoS2 and xwt % Flyash Hybrid Metal Matrix Composites

This research work aims to investigate the effect of SiCp and MoS2 lubricant particles on the tribological properties of AlSi7Mg alloy fabricated through stir casting and stir cum squeeze casting process. AlSi7Mg alloy is a supreme favourable industrial aluminium alloy owing to its exceptional casting ability, corrosion resistance and good strength to weight ratio. Stir casting is an effective and capable processing route for making aluminum composites with enhanced properties. Further to obtain improvised properties and pore-free structure aluminium matrix composites were fabricated through stir cum squeeze casting processing route. During the experimental investigation, AlSi7Mg alloy reinforced with 3 wt % MoS2 and 0, 5, 10 wt % of flyash is processed through stir casting and stir cum squeeze casting processing route. Tribological responses like wear rate and coefficient of friction were measured using Pin-on-Disc tribometer apparatus under dry sliding condition of load 10, 20, 30 and 40N with a constant sliding velocity of 3 m/s. The result shows that the addition of MoS2 lubricant particles and flyash reinforcement particles to AlSi7Mg aluminium alloy leads to increase in the wear resistance and coefficient of friction. There was a notable increase in the tribological properties with higher weight percentage addition of 10wt% fly ash and 3wt % MoS2. Also, addition of MoS2 lubricant particles in the AlSi7Mg/10wt% flyash/3wt % MoS2 hybrid metal matrix composites results in the reduction of metal to metal contact and subsequently leads to increase in the tribological characteristics of composite sample processed through stir casted and stir cum squeeze casting processing route. Combined effect of higher weight percentage of reinforcement addition and squeezing of liquid metal improvises the tribological characteristics of the AlSi7Mg/10wt% flyash/3wt% MoS2 hybrid metal matrix composites than that of the other combinations.