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对 Ａｌ７８３ Ｆｅ， Ａｌ５１６ Ｆｅ （ｗ ｔ％ ） 两种 Ａｌ Ｆｅ 快凝条带中不同冷速部位的组织进行了 Ｔ Ｅ Ｍ 分析，着重考察了 Ａｌ Ｆｅ 快凝合金的组织演化及其各竞争初生相的析出次序。结果表明： Ａｌ Ｆｅ 合金快凝组织与成分及熔体的冷速有关。对一定成分的合金， 当增加其熔体冷速时， 亚稳 Ａｌｍ Ｆｅ 相优先于 Ａｌ６ Ｆｅ 相析出， 初生α Ａｌ相优先于金属间化合物相析出。当合金中 Ｆｅ 含量越低，形成无初生金属间化合物相的单一 α Ａｌ 微胞晶相所需的临界过冷度越小。当两种 Ａｌ Ｆｅ 合金以相对较低的相同冷速快凝时，成分不同，其初生析出相不同，对于 Ａｌ５１６ Ｆｅ 合金而言， 优先析出 Ａｌｍ Ｆｅ 初生相； 而 Ａｌ７８３ Ｆｅ 合金中， 则优先析出 Ａｌ６ Ｆｅ 和二十面体孪晶初生相。
The T E M analysis was performed on the microstructures of Al783 Fe and Al516 Fe (w t% Microstructure Evolution of Alloys and Precipitation Sequence of Their Contemplative Primary Phase. The results show that the microstructure of AlFe alloy is related to the composition and the cooling rate of the melt. For a certain composition of alloy, when the melt cooling rate is increased, the metastable AlmFe phase preferentially precipitates from the Al6Fe phase, and the primary α-Al phase preferentially precipitates from the intermetallic compound phase. When the content of Fe in the alloy is lower, the critical undercooling required for forming a single α-Al microcell phase without the primary intermetallic compound phase is smaller. When the two Al-Fe alloy at a relatively low fast quenching at the same cooling rate, the composition is different, the primary precipitates are different, for Al 5 16 Fe alloy, precipitation of Alm Fe primary phase; and Al 7 83 Fe alloys, the preferential precipitation of Al6 Fe and icosahedral twins primary phase.