Effect of electromagnetic field on microstructure and macrosegregation offlat ingot of 2524 aluminium alloy
(Key Laboratory of Electromagnetic Processing of Materials,
Ministry of Education, Northeastern University, Shenyang 110819, China)
Ministry of Education, Northeastern University, Shenyang 110819, China)
Abstract: Low frequency electromagnetic casting(LFEC) process with the application of an induction coil outside the conventional direct chill (DC) casting mould was used to prepare the flat ingot of 2524 alloy and the effect of electromagnetic field on the microstructure and macrosegregation of this alloy was systematically studied. The results show that the flat ingot prepared by the LFEC process has a finer and more uniform as-cast microstructure and the grain morphology is transformed from dendrite and rosette-like to equiaxed structure. The LFEC process also shows a significant effect on macrosegregation, and with the application of electromagnetic field during casting process, the segregation in the centre of the ingot is obviously reduced. The mechanism of these effects was also discussed.
Key words: 2524 aluminium alloy; grain refinement; solidification; microstructure; macrosegregation; low-frequency electromagnetic casting