Based on the idea proposed by Taylor and Fidler of calculating the average entropy of solution per atom (△S1) ,the model for calculating △S1 of KF and BaTiO3 is established. The calculated △Sf of KF and BaTiO3 is 51. 662 J · mol-1 · K-1 and 65. 134J · mol-1 · K-1 respectively. Experimental results indicate that the undercooling required for BaTi3 to catalyze KF heterogeneous nucleation is 16 K,and the undercooling required for KF to catalyze BaTiQ3 heterogeneous nucleation is 43 K, from which, it follows that BaTiQ3 is the leading phase of KF-BaTiQ3 eutectic system. In compound-compound binary eutectic, the principle of non-reciprocity nucleation acts as in element-compound binary eutectics.%根据Taylor和Fidler模型的基本思路,建立了计算KF,BaTiO3两相平均原子溶解熵△Sf的模型,计算出两相的ASf分别为51.662 J·mol-1·K"和65.134 J·mol"·K-1.实验研究发现:BaTiO3促发KF形核的过冷度为16K,而KF促发BaTiO3形核的过冷度为43 K,据此判断出BaTiO3为KF-BaTiO3共晶的领先相,并证实两相促发形核的非互惠原则,在化合物共晶体系中依然成立.
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