对Zn-5%Al合金在不同液淬下拉速率和过热状态下的定向凝固液固界面形态进行了研究。结果表明,当合金熔体的过热温度分别为较低和较高时,随着液淬下拉速率的增加,定向凝固界面形态变化与一般的界面形态演化相比各自表现为相符和相异;定向凝固界面稳定性变化存在着若干个由液淬下拉速率和过热状态互相制约决定的分界点。 The morphology of the solidified liquid-solid interface of Zn-5% Al alloy under different liquid quenching rates and overheating conditions was studied. The results show that when the superheat temperature of alloy melt is lower and higher respectively, with the increase of liquid quenching rate, the morphological changes of directional solidification interface show the same and different compared with the general interface morphological evolution. Solidification interface changes in the stability of the existence of a number of liquid quenching pull-down rate and the state of overheating constraints each other’s decision point.