强磁场对Cu-90%Pb合金凝固中比重偏析的影响

EFFECT OF HIGH STATIC MAGNETIC FIELD ON SOLIDIFICATION STRUCTURE OF Cu-Pb MONOTECTIC ALLOYS

研究了强磁场对Cu-90%Pb合金中比重偏析的影响规律。结果表明:10T磁场下,当冷却速度达到100℃/min以上时,Cu-90%Pb合金中的重力偏析得到完全抑制;随着磁感应强度的增加,磁场对比重偏析的抑制作用增强。在30℃/min冷却速度下,12T磁场使该种合金凝固中的50微米直径颗粒上浮速度下降90%以上。理论分析表明:强磁场增加金属熔体粘度,降低自然对流,诱生洛伦兹力阻力来抑制颗粒上浮和聚合。

The influence of 10Tesla high magnetic field on gravity segregation of Cu-90% Pb monotectic alloys was investigated by experiment. The results showed that gravity segregation in Cu-90% Pb alloy was fully suppressed in 10Tesla high static magnetic field when cooling rate reaclaed 100/min or above. With increasing magnetic flux density, the effects of high static magnetic field was enhanced, and under cooling rate of 30℃/min and in 12Tesla magnetic field, the stokes rising rate of 50gm second phase particles were reduced by 90% or more. Theoretical analysis showed that magnetic field could increase viscosity of melt and restrain natural convection; also induce Lorentz resistive force to reduce rising velocity and growth rate of second phase particles.