Analysis of Amplitude Dependence of Internal Damping of AZ31 and AZ61 Alloys in Initial State and after Deformation

The article is focused on the analysis of amplitude dependence on the internal damping of magnesium alloys in initial state and after deformation. Resonance method, based on continuous excitation of oscillations of the specimen, was used in experimental measurements, with the entire apparatus vibrating at a frequency close to the resonance. The damping capacity, characterized by dissipation of mechanical energy, was examined in magnesium alloys of AZ31 and AZ61 type. These alloys have different contents of the main alloying elements and it is expected that they will have a significant impact on the measured course of amplitude dependencies of internal damping. Dependence of internal damping on amplitude was measured on test specimens after homogenization annealing without plastic deformation of the material and after different degrees of plastic deformation to determine the critical strain amplitude.