HOT COMPRESSION DEFORMATION BEHAVIOR OF Mg-Zn-Al-(Y) ALLOYS REINFORCED WITH QUASICRYSTAL

作者：Tong Jian; Huang Hua; Yuan Guangyin^*; Ding Wenjiang

来源：Acta Metallurgica Sinica, 2011, 47(12): 1520-1526.

DOI：10.3724/SP.J.1037.2011.00372

• Mg-Zn-Al-(Y) alloy
• icosahedral quasicrystal
• hot compression deformation
• dynamic recrystalization

Quasicrystal phase offers a good combination of strength and ductility due to the strong interface between the quasicrystal phase and the Mg-matrix. Hot compression tests of Mg-Zn-Al-(Y) based alloys reinforced with quasicrystal were performed on Gleeble-1500 thermal simulation machine at a constant deformation temperature of 230 degrees C and strain rates ranged from 0.0015 s(-1) to 1.5 s(-1). Microstructure evolution of hot-compressed Mg-Zn-Al-(Y) alloys and the relationship between flow stress and strain rate were studied. XRD and SAED results show that the microstructures of as-cast Mg-8Zn-4Al (ZA84) and Mg-8Zn-4Al-0.5Y (ZAY8405) are composed of icosahedral quasicrystal phase and alpha-Mg matrix. The quasicrystals in ZA84 and ZAY8405 alloys have a stoichiometric composition of Mg38Zn43Al19 and Mg51Zn30Al19 respectively. Dynamic recrystalization (DRX) take place during hot compression and the flow stress increases when increasing the strain rate at a constant compression temperature, which can be represented by the Power Exponential Equation. Deformation twinning and dynamic recrystalization are easier to take place in ZAY8405 alloys due to the refined and dispersed quasicrystal phase with Y addition.

• 出版日期2011-12-11
• 单位上海交通大学