Abstract
The hot working characteristics of the Mg-11.5Li-1.5Al-0.15Zr (wt.%) alloy have been studied using hot-compression testing in the temperature range 200– 400 °C and strain rate range 0.001– 100 s –1. On the basis of these data, a processing map for this material has been developed. The map exhibits a single domain with a peak efficiency of 53% occurring at 350 °C and 0.001 s– 1. On the basis of microstructural features, grain size variations and ductility variations, the domain is interpreted to represent dynamic recrystallization (DRX). Unlike in Zr-free alloy which exhibits only superplasticity, the Al3Zr particles in the Zr-containing alloy help in nucleating DRX and in refining the grain size. The material exhibits flow instabilities at temperatures higher than 350 °C and strain rates higher than 10 s– 1.
One of the authors (O.S.) would like to thank Dr. D. Banerjee, Director, Defence Metallurgical Research Laboratory, Hyderabad, India for permission to publish this paper.
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