Effect of alloying elements on the mechanical behavior and wear of austempered ductile iron

Abstract

This paper treats the effect of alloying elements on the modification of the microstructure and properties of austempered ductile iron. The basic cast iron was elaborated in an induction furnace, its solidification shows a ferrite-pearlitic structure. This cast iron was alloyed with Mn, Ni, Mo and V. The samples were cast in the form of cylindrical bars of 22 mm in diameter and 300 mm in length. They have undergone a bainitic heat treatment type. Microstructures were characterized by optical microscopy, "SEM" and "XRD". Tensile strength, hardness, microhardness, resilience and wear were determined and correlated with the microstructure. In the treated condition, metallographic study shows that the structures were formed of bainitic ferrite and feathery upper ausferrite. The results of mechanical tests and wear show that the cast irons studied achieve superior properties.