ABSTRACT
Ductile cast iron also referred to as nodular iron or spheroidal graphite iron. The Ductile Cast Iron contains graphite which is in the form of discrete nodules or spheroids. This paper deals with some factors influencing microstructure and mechanical properties of Ductile Cast Iron. Ductile Cast Iron have been used for a wide variety of application in automotive, rail and heavy engineering industry because of its excellent mechanical properties such as high strength with good ductility, good wear resistance and good fatigue properties. The properties of ductile cast iron depend on both chemistry and heat treatment. Nodular cast iron is primarily heat treated to create matrix micro structure and associated mechanical properties not readily obtained in the casted condition. Final structure and properties of Ductile Cast Iron are obtained by controlled process of heat treatment. The influence of heat treatment on microstructure and mechanical properties of ductile cast iron above austenising temperature is altered. Experiments were conducted on 600/3 and 500/7 grades of ductile cast iron and following observations were made to know the properties of metal. Results of the experiment shows that it dependence of temperature and various matrixes can be obtained (i.e. mixture of graphite, ferrite and pearlite). Different quenching media are selected to check the behaviour of the materials. Quenching Medias like vegetable oil, mineral oil and water were used for this experimental analysis. After heat treatment the tensile strength, hardness, elongation and yield stress of the specimens were obtained with respect to different quenching media.
