Effect of hot extrusion on microstructure and mechanical properties of quasicrystal-reinforced Mg-Zn-Y alloy

The microstructure and mechanical properties of as-cast and as-extruded Mg-Zn-Y alloy (Mg-11% Zn-0.9% Y, mass fraction) containing Mg-3 YZn6 quasicrystal were studied. The eutectic icosahedral quasicrystal phase (I-phase) is broken and almost distributes along the extrusion direction, and fine I-phase with nano-size is precipitated during the extrusion. The (alpha)-Mg matrix grains are refined due to recrystallization occuring during the hot extrusion. Some 1012 twins are observed in the extruded ZW1101 alloy. And (0002) 1010 fiber texture is formed in matrix alloys after hot extrusion. The extruded alloy exhibits high strength in combination with large elongation at room temperature. The strengthening mechanism of the as-extruded alloy was discussed.