LiCl-KCl-MgCl2-Gd2O3熔盐共电沉积制备Mg-Li-Gd合金

摘要

在823 K和973 K的条件下,采用恒电流密度共电沉积法在LiCl-KCI-MgCl2-Gd2O3熔盐体系中制备Mg-Li-Gd合金,并运用XRD、SEM、EDS和OM对所制备合金进行微观组织分析.结果表明:在开始的30 min内,主要是Mg和Gd的沉积,所得合金含96.53%Mg,3.20%Gd和0.27%Li(质量分数),然后Li迅速沉积.可以通过控制电解时间或改变Gd2O3的浓度调节Mg-Li-Gd合金的组成.XRD分析可知,在Mg-Li-Gd合金中存在Mg3Gd相和Mg2Gd相.从Gd元素的面扫描分析可知,Gd元素主要分布在Mg-Li-Gd合金的晶界处.Gd的添加增强了合金的抗腐蚀能力.%Mg-Li-Gd alloys were prepared by electrochemical codeposition from LiCI-KCl-MgCl2-Gd2O3 melts on molybdenum electrode with constant current density at 823 and 973 K. The microstructure of the Mg-Li-Gd alloys was analyzed by X-ray diffraction (XRD), optical microscopy (OM) and scanning electron microscopy (SEM). The results show that magnesium and gadolinium deposit mainly in the first 30 min, and the alloy obtained contains 96.53% Mg, 0.27% Li and 3.20% Gd (mass fraction). Then, the reduction of lithium ions occurs quickly. The composition of alloy can be adjusted by controlling electrolysis time or Gd2O3 concentration in LiCI-KC1 melts. With the addition of Gd into Mg-Li alloys, the corrosion resistance of the alloys is enhanced. XRD results suggest that Mg3Gd and Mg2Gd can be formed in Mg-Li-Gd alloys. The distribution of Gd element in Mg-Li-Gd alloys indicates that Gd element mainly distributes at the grain boundaries of Mg-Li-Gd alloys.