Numerical simulation and experiment validation of
thixoforming angle frame of AZ61 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)
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)
Abstract: Numerical simulation and experiment of thixoforming angle frame of AZ61 magnesium alloy were investigated. The results show that with the increase in punch displacement, cylinder billet firstly fills into die cavity of angle frame from feed inlet and plastic deformation occurs in touching region between billet and die cavity. After central thin wall of angle frame is created, semi- solid billet fills toward two edges. Lastly, complete plastic deformation occurs in billet, leading to complete filling of semis-olid billet. Effective strain, effective stress and billet temperature decrease with the increase in punch displacement. Effective stress decreases with the increase in billet temperature, die temperature and punch velocity. The optimal conditions decided by numerical simulation are as follows: die temperature of 450 ℃, billet temperature of 560 ℃ and punch velocity of 30 mm/s. Angle frame components with high mechanical properties such as yield strength of 225 MPa, tensile strength of 309 MPa and elongation of 21.8% and fine microstructure could be thixoformed successfully according to process parameters decided by numerical simulation.
Key words: AZ61 magnesium alloy; numerical simulation; semi-solid billet; thixoforming