Processing Maps for Use in Hot Working of Ductile Iron

The hot deformation characteristics of ductile iron are studied in the temperature range of 973 to 1273K and strain rate range of 0. 001 to 1 s−1 by using hot compression tests. Processing maps for hot working are developed on the basis of the variations of efficiency of power dissipation with temperature and strain rate. The results reveal that the flow stress of ductile iron is sensitive to strain rate. In the processing map under strain of 0. 7, a domain is centered at 1273 K and 1 s−1, and the maximum efficiency is more than 36%. According to the maps, the zone with the temperature range of 1173 to 1273 K and strain rate range of 0.1 to 1 s−1 may be considered as the optimum region for hot working.