| This paper aims to improve the morphology of Fe-riched phase in aluminum alloys by using the modification of Ce-riched rare-earth mixture and Mn. The effect of Fe content,cooling rate and modification content on Fe-riched phase, microstructure and mechanical properties of aluminum alloys were investigated.The investigative results show that, with cooling rate increasing, the morphology of Fe-riched phases decrease in commercial pure aluminum. When Fe content less than 1wt%, Fe-riched phase are fine particle, In contrary, Fe-riched phase are distributed in the form of short rodlike or long needlelike, when adding 0.5wt%RE in commercial pure aluminum with 1wt%～2wt%Fe , Fe-riched phase are fine particle. In commercial pure aluminum with 0.5wt%Fe, adding 0.3wt%RE obtains a tensile strength and an elongation of 117.4MPa and 50.6%respectively, enhancing by 38.6% and 15.5% than the unmodification.In Al-7Si-0.3Mg alloys with 0.12wt%Fe, adding 0.1wt%RE makes the Fe-riched phase and eutectic Si phase to be fine particles. Besides, the tensile strength and elongation can respectively achieve at 166MPa and 5.5%, by contrast with unmodification respectively enhanced by 10% and 94.3%. In Al-7Si-0.3Mg alloys with 0.2wt%Fe, adding 0.2wt%RE leads the Fe-riched phase and eutectic Si phase to be fine particles; the tensile strength and elongation can respectively achieve at 169MPa and 5.28%, enhancing by 14.2% and 21.9% than the unmodification respectively.In Al-7Si-0.3Mg-0.15RE alloys, when the Fe content achieves at 0.3wt%, Fe-riched phase are mostly needlelike. Mn modification to Al-7Si-0.3Mg-0.15RE alloys with 0.5wt%Fe greatly affects the morphology of Fe-riched phases. When the ratio of Mn/Fe is 1.4, the size of Fe-riched phase is the smallest; the elongation of the alloys can achieve at 13.1%, enhancing by 363% than the unmodification. When the ratio of Mn/Fe is 2, the Fe-riched phases are broken up; the tensile strength of the alloys can achieve at 180MPa, enhancing by 7.1% than unmodification.
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