Abstract
The internal stress during high temperature creep was investigated for the die-cast AM50 magnesium alloy at 473 K through the strain-transient dip test technique. The microstructure of the alloy is characterized by fine α-Mg grains together with the β-Mg17Al12 particles located on the grain boundaries. The internal stress is proportional to the applied stress, when the applied stress ranges below the yield stress. The ratio of the internal stress to the applied stress is 0.36 for the alloy, which is about half of those for conventional pure metals such as Cu, α-Fe and Ni. The small internal stress is a characteristic feature in the creep for the alloy.