Microstructures, Damping and Mechanical Properties of Mg-0.8Si Alloy under Different Rolling Strain Rates

Mg-0.8Si alloy plates were rolled at high strain rates of 15, 20, and 25 s −1 , and the effects of the rolling strain rate on the microstructure, mechanical properties, and damping properties of the Mg-0.8Si alloy were studied. With the increasing strain rate, the area fraction of DRX in the HSRRed Mg-0.8Si alloy gradually increases, resulting in the decrease in dislocation density and dislocation tangles. A higher strain rate can enlarge the grain size of the Mg-0.8Si alloy, so the basal texture and tensile strength can both decrease because of the increased strain rate. The maximal elongation is 8.40% at 20 s −1 . The damping properties of HSRRed Mg-0.8Si alloy increase with the strain rate and the critical strain amplitude gradually decreases.