Effects of heat treatment on the morphology of long-period stacking ordered phase, the corresponding damping capacities and mechanical properties of Mg-Zn-Y alloys

The effects of heat treatment on the morphology of long-period stacking ordered (LPSO) phase, the corresponding damping capacities and mechanical properties of Mg95.3Zn2Y2.7 dual phase alloys are investigated in the present study. The block, lamellar, and rod-shaped LPSO phases can be obtained through different heat treatment processes. The grain size changes minimally and no new phase is found in the processes. Comparison of the mechanical properties and damping capacities of the alloys with different morphologies, it reveals that the block LPSO are more conducive to the strength of the alloy and that the lamellar phases precipitated in the matrix decrease the elongation. Meanwhile, it can conclude that the appearance of the rod-shaped LPSO phase illustrates that damping capacities notably increase while maintain a high yield strength. The alloy, which features a rod-shaped LPSO phase, exhibits an ultimate tensile strength (UTS) of 210 MPa, elongation (EL) of 7.5%, yield strength (YS) of 100 MPa and damping capacity of 0.052 at ε = 10−3; as such, this alloy presents fine comprehensive performance.