No abstract

The suitability of using black palm kernel oil as austempering medium for ductile iron to be used in austempering agricultural implements was investigated. The ductile iron was cut and machined into tensile, impact, and hardness test samples, austenitized at 950 °C, soaked for 2 h, and quenched in the black palm kernel oil bath maintained at a temperature of 270 °C. The samples were held in this bath for 1, 2, 3, 4, and 5 h, respectively. Then, the tensile strength, hardness values, and impact energy of both the austempered and as-cast samples were determined. It was observed that austempering significantly increases the tensile strength and impact energy of the ductile iron apart from achieving an appreciable increase in hardness. Also, the tensile strength, hardness, and impact values obtained for the austempered ductile iron using black palm kernel oil tally with recommended values of standard ductile iron austempered in standard salt bath implying that black palm kernel oil can be used as bath for the austempering of ductile iron. The oil was used in austempering tractor spindle (disc carrier) and the practical result was successful.