铝的电渣精炼及其净化机制研究

探索高效净化新方法是发展优质铝及铝合金的重要技术基础之一。本项目创造性地提出了利用电渣精炼技术去除铝中杂质元素铁的综合净化新思路，将首先通过热力学分析，并结合对多元渣剂理化特性的分析与测试，选择并优化可用于铝电渣精炼处理且具有除铁效果的渣剂；再以多场耦合模拟分析为基础，揭示铝电渣精炼过程的温度场、流场与浓度场的耦合与演变规律；通过化学分析、组织观察与性能测试，探明铝中杂质铁与气体、夹杂含量，以及凝固组织、力学性能等随电渣精炼工艺参数的变化规律；结合电渣精炼过程的同步辐射X成像原位观察分析，在剖析电渣精炼除铁动力学条件的基础上，构建以多相反应与界面过程复合模型为基础的杂质元素的区域富集、反应与多相分离的电渣精炼除铁机制。本项目将探索实现气体、夹杂与杂质元素的同步去除和对凝固组织的有效控制，发展综合纯净化原理与技术，是传统黑色冶金技术在铝纯净化领域的尝试，将为优质铝材的发展提供技术支撑。

New efficient purification method is one of the important technical basis for developing high quality aluminum and aluminum alloys. A creative idea utilizing the electroslag refining technique is proposed to remove the impurity elements iron and purify the aluminum. Based on thermodynamic analysis, combined with the evaluation of physical and chemical properties of the multicomponent slags, the electroslag refining process and slags to eliminate iron impurity will be optimized. The multi-field coupling simulation will be carried out to reveal the evolution of the temperature field,flow field and concentration filed during aluminum electroslag refining process.Through chemical analysis, microstructure observation and performance testing, the effects of the procedure parameters on the change of the iron impurity content, gas and inclusions in aluminum,as well as the solidification microstructure will be discussed in detail. With the in-situ observation of the electroslag refining process by synchrotron radiation X-imaging technique, a composite model of multiphase reactions and interface processes of the iron removal mechanism will be build based on the kinetics analysis on the local enrichment, reactions and multiphase separation of the iron impurity during the procedure.This proposal will try to estabish an integrated method to remove the gas,inclusions and impurity elements simultaneously and control the solidification structure effectively. It is an attempt to utilize the traditional ferrous metallurgy technology in aluminum research and will promote the development of purifircation principles and techniques,which is believed to be the technical support for developing high-quality aluminum.