Hot Compression Behavior of Mg-14Li-6Al-1Ca Alloy

The hot deformation behavior of a Mg-14Li-6Al-1Ca alloy was studied using the hot compression true stress-strain curves corresponding to the temperature range of 473-673K at strain rates of 1 (c) 10(-1)-1 (c) 10(-3) s(-1). The true stress-strain curves indicated dynamic softening under the test conditions. The peak stress during deformation could be correlated with the temperature and strain rate using a hyperbolic-sine equation. The activation energy of the Mg-14Li-6Al-1Ca alloy was determined to be 193 kJ mol(-1). The Zener-Hollomon parameter (Z) for the Mg-14Li-6Al-1Ca alloy was determined. The tendency for dynamic recrystallization increases at low strain rates and high temperatures, corresponding to low Z values. The hot deformation behavior of the Mg-14Li-6Al-1Ca alloy was modelled by a suitable constitutive equation. Furthermore, the size of the equiaxed grains in the hot-deformed and quenched specimens was estimated from the Z value.