| 摘要 |
PURPOSE:To accelerate columnar crystallization and to improve magnetic characteristics, by applying a magnetic field to an Fe-Cr-Co magnet alloy so as to solidify the alloy in the stage of casting said alloy. CONSTITUTION:A raw material for a permanent magnet alloy consisting essentially of Fe:Cr:Co is melted and the molten alloy is charged into a casting mold installed between electromagnets under application of magnetic field. Then, eddy current is generated and convection is suppressed. Therefore, the critical value of the temp. gradient necessary for generation of convection is increased and the convection is suppressed in succession even after the start of solidification, thus the phenomenon of melt cutting is decreased and since the high- temp. state is maintained long, the melt cut crystal is easily remelted and the columnar crystallization is accelerated. |
