EFFECT OF VEGETABLE OIL QUENCHANTS ON THE PROPERTIES OF ALUMINUM DURING SOLUTION HEAT TREATMENT

Abstract

Proper selection of appropriate quenching media can result in improved mechanical properties of pure commercial aluminum after solution heat treatment. This paper presents the effect of heat extraction by groundnut, melon, palm kernel, shea butter and palm oils on the mechanical properties of various samples of pure commercial aluminum heat treated at 200 °C, 250 °C, 300 °C and 350° C. A muffle furnace equipped with a digital thermometer and a thermocouple was used for the solution heat treatment. Tensile strength and hardness tests were carried out using an Instron Universal Tester and Vickers hardness methods, respectively. The results showed that palm kernel oil cools faster at 200 °C and 250 °C, while palm oil and shea butter oil quench faster at 300 °C and 350 °C, respectively. Solution heat treatment with palm kernel oil offered the highest percentage elongation at 200 °C, while at 350 °C shea butter oil gave the best percentage elongation. The best among the bio-quenching oils in providing good ductility is shea butter oil at 200 °C, while at 300 °C and 350 °C groundnut oil gives the best result. Highest hardness values were obtained from samples quenched in melon oil between 200 °C and 300 °C. However, these values decreased with increased heating temperature, probably due to the density and viscosity variation with temperature rise. Similar observations were made on other samples quenched in other bio-quenchant oils used in this experiment. This study shows that locally available vegetable oils have promising potential to serve as a possible replacement for nonbiodegradable mineral oils in many applications.