Low-frequency damping properties of as-extruded Mg–11.2Li–0.95Al–0.43Zn magnesium alloy

Low-frequency damping capacities of as-extruded Mg–11.2Li–0.95Al–0.43Zn (LAZ1110) alloy are studied by dynamic mechanical analysis tests. Experimental results reveal that it is β-phase matrix with α precipitates in major. The heating internal friction Q−1(T) curves show P1, P2 and P3 peaks appearing at 30 °C, 107 °C and 215 °C, respectively, and P1 and P2 peaks have been reported, but P3 peak has not yet. P1 and P2 peaks are frequency-dependent and their activation energies are calculated as 0.85 eV and 1.02 eV, respectively. The heating Q−1(T) curves also show a significant high-temperature damping background (HTDB) at temperature above 275 °C and its activation energy is calculated as 0.75 eV which is relatively low due to the abundant α/β phase boundaries. XRD tests indicate that the textures are developed during recrystallization and grain growth of the heated specimens and the texture development is suggested to be closely related to the occurrence of P3 peak.

► The P1 and P2 are frequency-dependent with H of 0.85 and 1.02 eV, respectively.
► The heating Q−1(T) curves show a significant HTDB with activation energy of 0.75 eV.
► Textures are developed during recrystallization and are related to the P3 peak.