| Title |
Effect of Electro magnetic Stirring in Mold on the Reduction of Subsurface defects and Macrosegregation in CC Billets |
| Authors |
오경식(Kyung Shik Oh); 장영원(Young Won Chang); 박중길(Joong Kil Park) |
| Abstract |
The effect of an in-mold electro-magnetic stirring(MEMS) on the subsurface defects and macrosegregation in the CC billets has been examined by a plant test and a new evaluation method. The reduction behavior of macrosegregation by a combination stirring has also been discussed through analyzing the thicknesswise cast structures at the centre region and mushy zone depending on the various EMS conditions. It is found that the subsurface defects and macrosegregation can effectively be reduced under an optimum stirring condition. The reduction of macrosegregation in CC billets by (M+S+F) EMS appears to be caused by 1) increasing the flow resistance of solute enriched interdendritic liquid in the mushy zone due to highly close-packed fine equiaxed crystals, 2) decreasing the flow distance of solute enriched interdendritic liquid in the mushy zone due to increased solidification rate at the centre region, and 3) decreasing ferrostatic pressure at the time of macrosegregation formation caused by the shortened distance of crater end. |