The Effect of Section Size on Cooling Rate, Microstructure and Mechanical Properties of A356 Aluminium Alloy in Casting

This paper reports the cooling characteristics of cast components with varying section size. In this study aluminium alloy A356 is selected because it is widely used at automotive and aircraft industries in the form of components with varying section size. This study investigates how cooling rate and mechanical properties vary with varying section size. Experiment is performed that aluminium alloy ingot is heated in muffle furnace and poured in the moulds having mould cavity of varying dimensions. Cooling rate was measured using K type thermocouple during solidification of aluminium alloy. In order to investigate the effect of cooling rate on microstructure and mechanical properties microstructure analysis, impact test, tensile test, hardness test were performed. The results showed that mechanical properties of cast component of smaller section size are better. This is due to fast cooling rate of smaller section cast component make refining of the grain size of the aluminium alloy.