钢液非均质形核触媒效用的点阵错配度理论

Effect of lattice disregistry on the heterogeneous nucleation catalysis of liquid steel

对钢液凝固温度下各种化合物基底与钢液凝固形核相(δ-Fe和γ-Fe)的二维错配度进行了计算,并对点阵错配度与钢液非均质形核触媒效用的关系进行了分析和讨论.结果表明:基底与形核相的错配度δ越小,越有利于非均质形核.凝固过冷度的对数与基底和形核相的二维错配度近似呈线性关系.基底与形核相的错配度δ<8%,非均质形核效用显著.

Planar disregistries between various substrates and nucleated phases during liquid steel solidification were calculated. The relation between lattice disregistry and heterogeneous nucleation catalysis of liquid steel was analyzed. The results show that the smaller the disregistry is, the more effective the substrate is for promoting nucleation. The logarithm of undercooling is approximately linear with the disregistry between the substrate and the nucleated phase. A substrate is presumed as the highly effective nucleus for promoting nucleation if the disregistry between the substrate and the nucleated phase is lower than 8%.