32 - Improving the Properties of Austempered Ductile Iron

Abstract:

An investigation of the influence of austenite content on the properties of austempered ductile iron was undertaken. The "reacted" austenite content in the austempered structure was controlled by varying austenitizing temperature and, thus, the carbon content of the austenite during austenitizing. Ductile iron plates measuring 1.25 by 8 by 10 inches and containing 3.4C- 2.7%-0.26Mn-l.lNi-0.16Mwoe re austempered at 725F (385C). The properties evaluated included tensile properties, machinability and thermal expansion coefficient.