The processing map for hot working of Al alloy 201420vol.%Al2O3 particulate-reinforced cast-plus-extruded composite material has been generated covering the temperature range 300-500 °C and the strain rate range 0.001-10 s-1 based on the dynamic materials model. The efficiency η of power dissipation given by 2m (m + 1), where m is the strain rate sensitivity, is plotted as a function of temperature and strain rate to obtain a processing map. A domain of superplasticity has been identified, with a peak efficiency of 62% occurring at 500 °C and 0.001 s-1. The characteristics of this domain have been studied with the help of microstructural evaluation and hot-ductility measurements. Microstructural instability is predicted at higher strain rates above (1s-1) and lower temperatures (less than 350 °C). © 1994.