中文摘要：

根据不同成分的PbSnBi三元合金熔体在温度诱导下发生液-液结构转变存在可逆与不可逆的差异,文章分别选取不可逆液-液结构转变的Pb3.82Sn6.18Bi90和可逆液-液结构转变的Pb26Sn42Bi32合金熔体,在不同温度诱导下对其凝固行为及组织进行了研究。结果表明,不可逆液-液结构转变后的Pb3.82Sn6.18Bi90合金熔体的结晶形核率和凝固过冷度较发生转变前增大,且初生相和共晶相组织明显细化;而可逆液-液结构转变的Pb26Sn42Bi32合金熔体对凝固行为及组织的影响不大;文中还就相关作用机理进行了讨论。

英文摘要：

The reversibility and irreversibility of temperature-induced liquid-liquid structural transition（TI-LLST） has been observed in PbSnBi melts of different components.At different inducing temperatures,the solidification behavior and microstructures of Pb3.82Sn6.18Bi90 melt with irreversible TI-LLST and Pb26Sn42Bi32 melt with reversible TI-LLST were studied.Results show that the crystal nucleation rate and super-cooling degree of Pb3.82Sn6.18Bi90 melt that experienced the irreversible TI-LLST increased and the primary phase and eutectic phase became finer,and that the reversible TI-LLST had no obvious effect on solidification behavior and microstructure of Pb26Sn42Bi32 melt.The relevant mechanism was also discussed.