Abstract
Anelastic behaviour of the Mg-4wt.%Li has been studied using acoustic methods. Strain dependence of the logarithmic decrement was measured at room temperature after the thermal treatment of samples. Activation volume for dislocation motion has been estimated depending on the annealing temperature. Temperature relaxation spectrum of the internal friction was measured in the temperature interval from room temperature up to 380°C at three frequencies in the multi-frequentional mode. Two internal friction peaks appeared in the first heating sub-circuit. While the low temperature peak vanished during the first cooling, the high temperature peak remained stable during three heating cooling loops. The high temperature peak has been ascribed to the grain boundary sliding.

Key words
magnesium alloy, damping, internal friction, dislocation motion, grain boundary sliding

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