Dynamic microstructural changes during hot extrusion and mechanical properties of a Mg-5.0 Zn-0.9 Y-0.16 Zr (wt.%) alloy

► At the beginning of hot extrusion the twins such as {101¯2} twins are formed. ► The main DmRX mechanism is the continuous DRX near the original grain boundaries. ► DRX seldom occurs in the twins and massive substructures formed in original grains. ► Quasicrystalline phase can accelerate DRX by obstructing the slip of dislocations. ► The extruded alloy shows yield strength: 317 MPa, UTS: 363 MPa and elongation: 12%.