Influence of mechanical cycling on damping behaviour of short fibre-reinforced magnesium alloy QE22

The influence of high cycling on the damping behaviour of QE22 magnesium alloy reinforced by short Saffil fibres was investigated. The damping was measured as a logarithmic decrement of free vibration. Mechanical cycling was done in the apparatus for damping measurement at room temperature. Variation of the strain amplitude independent component of the damping was found with increasing the number of cycles. Changes in the dislocation substructure due to dislocation–dislocation and dislocation–interface interactions are responsible for this effect.