Preparation and thixoforging of semisolid billet of AZ80 magnesium alloy
(1. School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China;
2. Postdoctoral Mobile Station of Mechanical Engineering, Harbin Institute of Technology, Harbin 150001, China;
3. School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China;
4. Postdoctoral Mobile Station of Mechanics, Harbin Institute of Technology, Harbin 150001, China)
2. Postdoctoral Mobile Station of Mechanical Engineering, Harbin Institute of Technology, Harbin 150001, China;
3. School of Mechatronics Engineering, Harbin Institute of Technology, Harbin 150001, China;
4. Postdoctoral Mobile Station of Mechanics, Harbin Institute of Technology, Harbin 150001, China)
Abstract: Semisolid billet of AZ80 magnesium alloy was prepared by new strain induced melt activated (new SIMA) process and thixoforging experiment was performed. The results show that after as-cast AZ80 magnesium alloy is processed by equal channel angular extrusion, microstructure is refined well due to heavy dynamic recrystallization occurring in severe plastic deformation. Compared with semisolid isothermal treatment and conventional SIMA, semisolid billet with fine and spheroidal grains are achieved in new SIMA. Thixoforging process of semisolid billet prepared by new SIMA has many advantages such as good surface quality of final component, high ability to fill cavity and net-shape. The fine and spheroidal grains and high mechanical properties such as tensile strength of 298 MPa and elongation of 28% can be developed in final part thixoforged.
Key words: AZ80 magnesium alloy; semi-solid forming; thixoforging; semisolid billet; strain induced melt activation