Creep behavior of Mg-2Nd-0.5Zn-0.4Zr at ambient temperature

The creep behavior of Mg-2Nd-0.5Zn-0.4Zr alloy was investigated at ambient temperature in the present work. It was observed that creep strain is significant dependence of the thermal fluctuation at low temperature and the minimum creep rate was extrapolated. The stress exponent was determined to be 2.8 and the apparent activation energy for creep deformation was determined to be 24 kJ/mol. However, the activation energy controlled by the threshold stress was determined to be 10.8 kJ/mol, which indicates creep deformation can occur at ambient temperature in magnesium alloys. TEM results show that dislocation glide on basal plane is a major deformation mechanism and mechanical twinning was also observed during creep deformation process. (C) 2010 Elsevier B.V. All rights reserved.