Experimental Analysis of Mechanical Properties, Wear and Corrosion Characteristics of IS600/3 Grade Ductile Iron Casting

Ductile iron castings, that comply with IS600/3 grade is used for the current study. On the basis of earlier research, the castings were austenitised at 900°C for 120 minutes duration and quenched in a bath of salt containing potassium nitrate and sodium nitrate in the ratio of 55:45 and held at temperature of 310°C for the duration of 120 minutes in an austempered treatment process. The outcome of above procedure was austempered ductile iron casting, which comprise graphite nodules in a matrix of bainite [1, 2]. The outcome of heat treatment process, after making the required specimens in both conditions (i.e. as cast condition & heat treated condition) on mechanical properties [13], wear and corrosion characteristics were investigated and a comparison was made with the as cast state of ductile iron. Properties such as UTS, percentage elongation, hardness values and impact strength values were investigated. Dry sliding wear test was attempted to measure the weight loss of prepared samples in both conditions (i.e. as cast condition & heat treated condition); using machine with pin and rotating disc arrangement. Dry sliding wear test was conducted by applying three loads condition (i.e. 300gm, 400gm and 500gm) and three speeds conditions (i.e. 950r.p.m, 1430r.p.m and 2130r.p.m). Corrosion test was conducted to investigate corrosion rate at temperatures, 35°C and 45°C for increasing testing time from 2 hours to 24 hours. The outcome of the study indicates that the heat treated specimens have higher UTS (25% increase), percentage elongation (27.88% increase) and hardness (10.60% increases) in comparison to the as cast specimen. From the wear test, it has been found that heat treated samples have excessive resistance to wear in comparison to the as cast samples and corrosion rate in heat treated testing samples are less in comparison to as-cast testing samples.