電磁振動がSn-10 mass%Pb合金のマクロ偏析に及ぼす影響

抄録

Control of segregation during the solidification of an alloy is important to improve the quality of product because it affects mechanical, physical and chemical properties. Convection is a tool of solute distribution control in the alloy though it is difficult to excite flow in the latter stage of the solidification using traditional method because of drastic increase in apparent viscosity. Thus, a controlling method of the solute distribution in the latter stage of the solidification is desired. In this study, electromagnetic vibration excited by a horizontal static magnetic field of 0.3 T and a vertical alternating current of 60 A, 1 kHz was applied to the Sn-10 mass%Pb during its solidification for clarification of its effect on the solute distribution, especially in the latter stage of the solidification. Both distributions of Pb concentration in the primary phase and the ratio of the eutectic phase area were explained by the gravity segregation when the electromagnetic vibration was not imposed. On the other hand, the Pb concentration in the primary phase increased if the electromagnetic vibration was imposed in the latter stage of the solidification, while it decreased if the imposing duration was the initial stage. The eutectic area ratio distribution became relatively uniform if the electromagnetic vibration was imposed both in the initial and the latter stages of the solidification. These distribution differences with and without the electromagnetic vibration suggest that the electromagnetic vibration induced flow in the solidifying alloy even though high solid fraction.