The developed model of diffusion-limited and diffusionless solidification of a eutectic alloy describes the relation “undercooling (ΔT)-velocity (V)-interlamellar spacing (λ)” for two cases. Namely, when the solidification front velocity V is smaller than the solute diffusion speed in bulk liquid V_D, V < V_D, the model predicts a regime of eutectic solidification similarly to known classical models. If the solidification front velocity V is higher than the diffusion speed, V > V_D, the solidification is mainly controlled by kinetic and thermal undercoolings. New expressions for the solute distribution coefficient and slope of the liquidus lines are supplied. The influence of the model parameters on the growth kinetics during eutectic solidification is discussed. Model predictions are compared with experimental data for the solidification of an Fe–B alloy with eutectic composition. Computational results show that the model agrees well with experimental data especially for low and high undercoolings, extending the undercooling range that can be covered by sharp interface modeling.

中文翻译：

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快速共晶凝固中局部非平衡的影响——第 2 部分：影响分析和与实验的比较

共晶合金的扩散限制和无扩散凝固的开发模型描述了两种情况下“过冷 (Δ T ) - 速度 ( V ) - 层间距 (λ)” 的关系。即，当凝固前沿速度V小于本体液体中的溶质扩散速度V _{D 时}，V < V _D，该模型预测了类似于已知经典模型的共晶凝固状态。如果凝固前沿速度V高于扩散速度，则V > V _D，凝固主要由动力学和热过冷控制。提供了溶质分布系数和液相线斜率的新表达式。讨论了模型参数对共晶凝固过程中生长动力学的影响。将模型预测与具有共晶成分的 Fe-B 合金凝固的实验数据进行比较。计算结果表明，该模型与实验数据吻合良好，特别是对于低过冷度和高过冷度，扩展了锐界面建模可以覆盖的过冷度范围。