Effect of magnetic alternate stirring on solidification structure of the round billet

Abstract

ABSTRACT In this study, a permanent magnet stirrer was constructed for the implementation of experiments on different magnetic field stirring modes. Through experiments, it can be observed that when the fixed speed of 200 rpm and the alternate stirring mode of magnetic field was adopted, the loose area in the core of ingots was reduced from about 72 mm2 to 21 mm2, which significantly improved the density and element uniformity of the ingot. A Φ220 mm SAE1527 round billet was selected as industrial trial steel. When the stirring current and frequency was 350 A and 3 HZ, the electromagnetic stirring of the mold was adjusted from continuous stirring to alternate stirring mode. The solidification structure of the billet has been improved to a certain extent. Furthermore, the number of spot segregation larger than 0.5mm2 was reduced from 43 to 26, thereby improving the uniformity of internal elements in the billet.