Damping behaviour of a Mg–Al–Ca alloy reinforced by short Saffil fibres

Magnesium alloy AX41 reinforced with short Saffil fibres was cycled between room temperature and increasing upper temperature of the thermal cycle. The amplitude dependence of the logarithmic decrement has been measured at room temperature after thermal treatment. An increase in decrement was observed in both amplitude independent and amplitude dependent component of decrement up to upper temperature of the thermal cycle of 310 °C. Thermal cycling at higher temperatures decreases the decrement. Changes in the microstructure are reason for such behaviour. Newly created dislocations at the interface between metallic matrix and ceramic fibres contribute to internal friction. Recovery processes occurring at higher temperatures decrease the decrement.