Determination of Abrasive Wear Behaviour of Al-Fly ash Metal Matrix Composites Produced by Squeeze Casting

Abstract

Squeeze casting is one of the processes in liquid metallurgy in which a molten metal is poured into a metallic die and is solidified under the action of a relatively high external pressure. The primary objective of this paper is to study the influence of the process parameters on wear resistance and hardness of squeeze cast LM6 Al-flyash composite. In this investigation Aluminium metal matrix composites, reinforced with flyash (from 5% to 12.5%wt.) was synthesized using stir-squeeze casting route. The influence of parameters like reinforcement content and squeeze pressure on the hardness and wear rate has been studied. The experimental results of the hardness and wear rate of the composites are compared with base alloy produced by squeeze casting. The results have shown that the wear resistance of the composites is very much superior to that of the base alloy produced by squeeze casting method. The abrasion tests were carried out by using a dry sand-rubber wheel abrasion wear testing machine. The test was carried-out at three different speeds (250, 300 & 350 rpm) and loads (2kg, 3kg & 4kg). The hardness test was conducted using Brinnel’s hardness tester. The macrostructural and microstructural studies of the MMCs were made using the TESCAN – VEGA3 scanning electron microscope in order to investigate the distribution of flyash particles in the matrix and on observation it was found that there is a reasonable uniform distribution of flyash in the matrix without any voids and discontinuities.