Effects of Solidification Time on Mechanical Properties and Wear Behaviour of Sand Cast Aluminium Alloy

An investigation was carried out to understand the effects of solidification time of the cylindrical specimen on hardness, wear rate and the coefficient of friction of Aluminium alloy (LM4). The commercially available LM4 Aluminium alloy was melted in a crucible furnace under argon atmosphere. The molten metal was poured into sand moulds having dissimilar size holes. The cast rods were tested for Vickers micro-hardness, wear rate and the coefficient of friction. The solidification time increases from 0.22 to 0.61 seconds when the diameter varied from 20 to 35mm. It was found that the hardness of the alloy vary with the diameter of the rod. Wear rate is inversely proportional to the hardness of the alloy. It was observed that the yield strength and tensile strength are increases with hardness, whereas the % elongation decreases. Further, the coefficient of friction is independent of hardness and not affected by the sliding time. Wear rate decreases linearly with hardness.