KBF_4去除Al-7Si合金中Fe相杂质及对组织的影响

Effects of KBF_4 on Elimination of Iron Phase Impurities and Microstructure in Al-7Si Alloy

通过热力学计算和分析添加KBF_4去除Al-Si合金中杂质Fe相的可行性,并利用金相显微镜、扫描电镜、能谱仪和XRD等,研究了Al-7Si合金中添加KBF_4后合金组织形貌和析出的沉淀相。结果表明,熔炼温度为1 013K,加入精炼剂除气除渣,再加入1.6%的KBF_4,保温30min后静置沉淀,Fe含量从1%下降到0.68%。XRD分析经过沉淀后的试样底部组织,发现生成了Fe_2B与AlB_2。KBF_4对铝合金除Fe的同时又能起到细化铝合金晶粒尺寸的作用。

Feasibility of added KBF4 to remove iron phase impurities in Al-Si alloy was carried out by thermodynamic calculation and analysis,and change of microstructure and precipitated phase in Al-Si alloy with KBF4 addition were investigated by means of metalloscope,scanning electron microscope,energy dispersive spectrometer and X-ray diffraction.The results reveal that Fe content in Al-7Si alloy is decreased from 1% to 0.68% with melting at 1 013 K,degassing and slag removal by adding refining agent as well as adding 1.6% KBF4 for 30 min.The Fe2B and AlB2 are generated at bottom of the samples after precipitation by XRD analysis.KBF4 can remove the iron from the aluminum alloy and refine the grain size in the aluminum alloy.