Investigation Of T-shaped Workpiece Semi-solid Aluminum Alloy Filling-plastic Flowing In Thixoforging

Semi-solid metal forming is a new metal processing technology, it has been a great development in recent decades, and it is used widely in commercial donation in western countries. The research of semi-solid metal forming of china is behind the western countries, it has not been achieved mass production. The semi-solid filling-plastic flowing integrated forging process of semi-solid Al alloy is induced in this paper. The semi-solid billet in mold cavity is filling and concreting at a lower pressure and gets the shape which is similar to workpiece. Then solidification metal is forced to move into the space which is made by activity module in die during the time elevating pressure to a constant value. The true plastic deformation is achieved under pressure and it results in high mechanical properties of workpiece. The semi-solid 6061 aluminum alloy forming rule is conclude according to the varied sliding block and local loading.The original microstructure of hot extruded bar is not uniform, and the satisfactory semi-solid billets can't be achieved by heating directly, so the semi-solid billets of 6061 aluminum alloy are prepared with the method of upsetting at the first stage. Severe bending is found during the time of directly upsetting, the methods of external constraints and the first hot billet upsetting then cold upsetting at condition of annealing are used in order to get good appearance, uniform microstructure, refining grain and better spheroidization. Rigid visco-plastic constitutive model of semi-solid 6061 Al alloy was established at different temperature and different strain rate.The thixoforging process of semi-solid 6061 Al alloy was simulated by commercial ?nite element software named Deform-3D. Temperature field, fluid field and stress-strain are considered in numerical simulation. The ?uid and effective stress–strain ?elds in the thixoforging process were obtained and the relationships among stress, strain rate and temperature also were analyzed.Forming equipment of T-shaped workpiece is used for forming the workpiece of semi-solid 6061 alloy. Distribution of real density and hardness with different location of the part is founded. The regular of mechanical properties of semi-solid workpiece with local loading were investigated according to true density and mechanical properties of different locations of workpiece.