Effects of Heat Treatment on the Morphology of Long-Period Stacking Ordered Phase and the Corresponding Damping Capacities of Mg-Cu-Mn-Zn-Y Alloys

Abstract

Different cooling processes of solid solution treatment, such as quenching in water and cooling in furnace, were introduced to Mg–3Cu–1Mn–1.8Zn–10Y (mass%) alloy. The morphology of long-period stacking ordered (LPSO) phase and the corresponding damping capacities were investigated in the present study. The block-shaped and the lamellar-shaped LPSO phases can be obtained through different cooling processes. Furthermore, the lamellar-shaped 14H LPSO phase grew and ran through the whole grains. Comparison of the damping capacities of the alloys with different morphologies, it reveals that the lamellar LPSO phases precipitated in the matrix are more conducive to the damping capacity that Q⁻¹ ≥ 0.052 at strains exceeding 1 × 10⁻³. The grain size is almost same and no new phase is found after the processes. Meanwhile, it can conclude that the sample cooled in the furnace exhibits higher damping capacity due to the coarse grains and formation of lamellar-shaped 14H LPSO phase.