二元合金凝固过程微尺度热质传输的影响分析

EFFECT OF MICRO SCALE HEAT AND MASS TRANSFER ON SOLIDIFICATION OF BINARY ALLOYS

针对二元合金凝固的微观偏析现象建立一维平面枝晶模型,考虑溶质在固相中有限扩散,液相完全扩散的情况。通过模拟计算,比较分析了Al-Cu和Fe-C合金微观偏析的特点,并讨论了不同凝固速度以及溶质扩散系数随温度变化与否对微观偏析的影响。分析结果表明,温度场的影响是不可忽略的,应该在研究中予以考虑。

One dimensional platelike dendritic model was developed describing the microsegregation during binary alloy solidification, considering solid back-diffusion and complete diffusion in the liquid. The specialties of microsegregation of Al-Cu and Fe-C alloys were compared and analyzed by simulation. Moreover, the effect of different solidification velocity on microsegregation was discussed, as well as the influence of solute diffusion coefficient varied with or without the temperature. The results of the analysis indicated that the effect of the temperature field was not negligible and should be considered in the research.