Numerical simulation and experimental research on electromagnetic field-flow field during solidification of semi-solid A356 aluminum alloy under electromagnetic stirring

A two-dimensional finite element model of magnetic field and a three-dimensional finite element model of flow field were established by using numerical simulation to study the effects of electromagnetic stirring parameters on magnetic induction strength,electromagnetic force,and the maximum flow rate of semi-solid aluminum alloy melt,as well as on the primary phase.The results show that the electromagnetic force in the melt gradually increased from inside to outside due to the skin accumulation effect,and the magnetic induction intensity show the characteristics of“small center and large edge”with the increase of electromagnetic frequency,and reach the maximum value at 0.80R−0.85R of the radial direction of the crystallizer.When the electromagnetic stirring frequency is 25 Hz,the current is 4 A,and the stirred time is 12 s,the melt flow rate is the largest compared with other parameters.The morphologies of primary phases of semi-solid A356 aluminum alloy cast at 650℃are the best after electromagnetic stirring at 590℃for 10 min at stirring parameters of 590℃,30 Hz,4 A and 12 s.Finally,the microstructure of semi-solid A356 alloy with the average grain equal-area circle diameter of 80.6μm and the shape factor of 0.78 is obtained.