Effect of hot extrusion on microstructure and mechanical properties of quasicrystal-reinforced Mg-Zn-Y alloy
(1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;
2. Department of Mechanical Engineering, Nagaoka University of Technology,
Nagaoka 940-2188, Japan;
3. Institute of Materials Engineering, GKSS-Research Center, D21502,
Geesthacht, Germany)
2. Department of Mechanical Engineering, Nagaoka University of Technology,
Nagaoka 940-2188, Japan;
3. Institute of Materials Engineering, GKSS-Research Center, D21502,
Geesthacht, Germany)
Abstract: The microstructure and mechanical properties of as-cast and as-extruded Mg-Zn-Y alloy (Mg-11%Zn-0.9%Y, mass fraction) containing Mg3YZn6 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 α-Mg matrix grains are refined due to recrystallization occuring during the hot extrusion. Some {10(-1)2} twins are observed in the extruded ZW1101 alloy. And {0002}〈10(-1)0〉 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.
Key words: magnesium alloys; quasicrystal; extrusion; microstructure; mechanical properties