(中南大学 材料科学与工程学院, 长沙 410083)
摘 要: 在非真空条件下用氟化物熔盐体系镁(铝)热还原法制备了Al-Mg-Sc中间合金, 讨论了金属还原剂的选择及还原温度、 时间等工艺条件对钪收率的影响, 并研究制定了氧化钪固相氟化制备氟化钪熔盐工艺。采用Al-Mg合金熔体为还原剂经二次还原后钪收率>80%, 制备的Al-Mg-Sc中间合金铸锭中钪含量>1.9%, 最佳的还原反应温度为1100K, 还原时间40min.。 氟化钪还原产生的初生态钪与铝作用形成稳定的Al3Sc化合物, 促进了还原的进行,使钪收率得到了大幅度提高。
关键字: Al-Mg-Sc中间合金; 镁(铝)热还原; 氟化钪;氧化钪
(School of Materials Science and Engineering,
Central South University, Changsha 410083, China)
Abstract:Al-Mg-Sc master alloy was prepared. The scandium fluoride melt salt was produced by fluorination reaction using Sc2O3 and NH4HF2. Scandium fluoride was reduced with magnesium(aluminum) melt in fused salt containing alkali and alkaline fluoride. The effect of the kind of metallic reducing agent and reducing condition such as reducing temperature and time, on the recovery of Sc in master alloys were studied. When the aluminum-magnesium melt was used as the reductive agent, the recovery would exceed 80% and the content of Sc in master alloy prepared would exceed 1.9%(mass fraction). The best reducing reaction temperature and time is 1100K and 40min, respectively. The primary Sc producing from reduction reacts with Al combines the stable compound Al3Sc, which sustains the reduction progress and promotes the recovery of Sc effectively.
Key words: Al-Mg-Sc master alloys; Mg(Al) thermoreduction; scandium fluoride; scandium