Influence of the grain size on the strain rate sensitivity in an Mg–Al–Zn alloy at moderate temperatures

The effect of grain size on the strain rate sensitivity (SRS) of the magnesium alloy Mg–3 wt.%Al–0.75 wt.%Zn has been investigated. It is shown that the SRS increases strongly for decreasing grain size below 15 μm. There is a close correlation between the SRS and the work hardening behavior. The current models are not capable of explaining this grain size dependence. The experimental results give a clue about an increasing contribution of grain boundary sliding to deformation.