Mayeedul Islam 1,*, S. M. Najmul Hoque2, M. Abdullah Al Mahmood2, A. A. Shisir 2
Aluminium and their alloys are widely used as construction materials from house hold appliances to air-craft parts. The commercially pure aluminium has merely low corrosion resistance and hardness compare to aluminium alloy. In this study an attempt has been made to study the influence of heat treatment on the properties of commercially pure aluminium. The investigation was consisted of identification of commercial aluminium through colour identification in chemical test and its subsequent heat treatment. The experimental parameters were heating temperature, cooling rate and quenching medium. The prepared specimen were heated at 300, 500 and 600 °C and then subsequently cooled either in open air, slowly in the furnace or quenched in furnace oil. Hardness of the heat treated and without heat treated specimen was measured in the Rockwell Scale. Corrosion resistance of the sample was evaluated in 3.5 % sodium chloride solution by weight loss method. It was found that specimen heat-treated at 500 °C showed higher hardness and corrosion resistance compare to that heat-treated at 300°C and 600 °C. Oil quenching specimen provided maximum hardness and corrosion resistance compare to slow furnace cooling and air cooling. So, it is said that hardness and corrosion resistance of commercially pure aluminium (99 % pure) could be improved through heat treatment at 500 °C and subsequent quenching in oil.
Keywords: Aluminium; Corrosion resistance; Heat treatment.