The relationships among microstructure, impact toughness and wear resistance in newly developed austempered low alloy white cast iron

This study investigated the relationships among microstructure, impact toughness, and wear resistance of newly developed Austempered Low Alloy White Cast Iron (ALAWCI). For austempering, the low-alloyed white cast iron samples were austenitized at 900 degrees C, then quickly quenched into a salt bath at 375 degrees C and kept at this temperature for different periods in the range of 15-420 min, then cooled to room temperature in still air. Optical, scanning electron microscopes, and XRD analysis were used for microstructural characterization studies. The impact toughness and wear resistance of as cast and austempered samples were determined. Experimental results showed that after austempering heat treatment, the metal carbide network kept its morphology without much change, but the matrix consisted of an ausferritic structure. Austempered low alloy white cast iron exhibited a good combination of impact toughness and wear resistance compared to low alloy as-cast white cast iron.