Solid particle erosive behaviour of sillimanite reinforced aluminium metal matrix composites

The Sillimanite reinforced metal matrix composite of 5, 10 weight percent was fabricated by vacuum assisted stir casting method and their properties such as density, hardness, tensile and impact strength are reported. For comparison pure aluminum is taken into consideration and found that the addition of sillimanite reinforcement increase the hardness, tensile, impact strength only in 5 wt % after that there is no substantial improvement in the mechanical properties. The erosive behaviour of sillimanite reinforced aluminum metal matrix composites is evaluated at different experimental conditions. Alumina is used as erodent materials. The varying operating conditions are the erodent velocity within 41, 72 and 100 m s⁻¹, angle of impingement within 45, 60 and 90 degree on the prepared composite. It is witnessed that, at higher velocity, the erosion rate is higher irrespective of reinforced metal matrix composites and pure aluminum (Al). At lower impingement angle, the erosion rate of the pure Al is greater than the reinforced composites. The effect of addition of reinforcement reduces the erosion rate of the composites at certain level i.e. up to 5wt % only; beyond this addition of reinforcement is not having any significant effect in the reduction of erosion rate. The erosion rate of 10 wt % reinforced composites is higher than the pure Al. A dimensional analysis is also performed to correlate the relation between the erosion rate and input parameters. (paper)