A new method has been proposed to prepare Mg-Al-Si master alloys by utilizing scrap Al-Si-Fe alloys with higher Fe levels,which aims to segregate Fe from Al-Si-Fe alloys by Mg melt.The segregation behaviors,microstructure morphology and evolution mechanism of iron-rich phases in Mg-Al-Si alloy melts were studied,after Al-14Si-4Fe(wt%) alloys were added and dissolved completely.In the Mg-Al-Si alloys,iron has very little solubility and tends to combine with other elements to form intermetallic phases,which grow into a deposition layer due to the higher density.During the cooling and solidifying process of Mg-Al-Si melts,the needle-like Al5 SiFe phase in Al-14Si-4Fe alloy evolved into blocky Al_5Fe_2 and Al_(0.7)Fe_3Si_(0.3) phases.Besides,the Fe levels of the Mg-Al-Si master alloys were reduced to 0.017 wt%from nominal content of 0.164 wt%.Based on the above results,this work carried out a semi-quantitative phasecompositions analysis for the deposition layer by relative intensity ratio(RIR) method,and evolution mechanism of the iron-rich phases had also been discussed.This study has paved a new way to regenerate the scrap Al-Si-Fe alloys,which has a great significance of promoting the recycling of aluminum resources.
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