Hot compression behavior of the Mg-Gd-Y-Zn-Zr alloy filled with intragranular long-period stacking ordered phases.

The compression behavior and mechanical properties of the Mg-6.9Gd-3.2Y-1.5Zn-0.5Zr (wt.%) alloy filled with intragranular long-period stacking ordered (LPSO) phases were investigated. This alloy possesses a high activation energy of ∼359 kJ/mol, because intragranular LPSO phases inhibit the lattice rotation of α-Mg matrix and may provide back stress. Compression temperature and strain rate (i.e. Zener-Hollomon parameters) combine to influence the DRX (ratio and grain size), workability, and mechanical properties, while the effect of strain rate on the DRX-ed grain size may be reduced at the compression temperature of 450 °C. The alloy compressed at 420 °C and 0.002 s −1 exhibits the superior strength because of the finer DRX-ed grain size, larger number of dynamic precipitates and kink bands. However, dynamic precipitates deteriorate the ductility and workability. [ABSTRACT FROM AUTHOR]