PRODUCTION OF CASTING HAVING TWO-LAYERED STRUCTURE

摘要

PURPOSE:To aggregate uniformly primary crystals to the surface part of a casting mold where cooling is fast and to form a casting having two-layered structure contg. internally no primary crystals by cooling the multiphase alloy melt in the casting mold to solidify under induction stirring in a rotating magnetic field. CONSTITUTION:The casting mold contg. the multiphase alloy melt is place on a rotary base and is rotated and cooled in the powerful magnetic field. The molten metal is inductively stirred in the rotating magnetic field and is cooled from the surface part of the casting mold. The primary crystals are uniformly prcipitated and aggregated to the surface part where the cooling is fast. The casting having the two-layered structure contg. no primary crystals is thus formed. The casting having the two-layered structure is satisfactorily formed without the local integration and aggregation of the primary crystals as in the conventional centrifugal casting method.