Influence of Thermomechanical Treatment on the Damping Capacity of Selected Magnesium Alloys

In the paper the temperature and amplitude dependence of internal friction in the AZ31, AZ63 and AZ91 alloys is reported. A rapid increase in internal friction with increasing temperature was estimated. Internal friction peaks were observed in AZ63 and AZ91 alloys. Position and height of the peaks in the temperature scale depends on the heating rate. Simultaneously, microstructural observations were performed in the selected points of the temperature scale. The amplitude dependence of internal friction in an AZ31 alloy, prepared by rolling, was measured. A significant influence of the rolling texture has been estimated. Main mechanisms of internal friction are connected with precipitation, dislocation motion and twinning.