Abstract: Based on the micro theory of metal mechanical property，combining with the analysis result of the influence of alloy elements on the property of magnesium alloy grain, the mechanism of damping characteristics of magnesium and magnesium alloy in the vibration deformation process is studied. Through theoretical derivation and experimental verification, it is indicated that with the increase of strain amplitude before macroscopic yield, the damping mechanism can be divided into four stages: resonated damping during dislocation elastic deformation, static hysteresis damping during dislocation break loose pinning(slip breeding), during dislocation line entwisted, and during slip band generated. The quantity of dislocation sources and their equilibrium state are influenced by the content and distribution of impurities or alloy elements, then the damping capacities and characteristic parameters of each stage are also influenced. Through this study, theoretical basis are provided for the design and manufacture of high-damping magnesium alloy.

Key words: Damping capacity, Dislocation, G-L model, Magnesium and magnesium alloys, Metal mechanical, Strain amplitude