Experimental study and thermodynamic calculation of Lu₂O₃-SiO₂ binary system

叶信宇^1,2，罗洋¹，刘松彬¹，侯得健¹，杨凤丽¹

1. School of Metallurgy and Chemistry Engineering Jiangxi University of Science and Technology

摘 要：As a binary system of BaO-Lu₂O₃-SiO₂ ternary system, Lu₂O₃-SiO₂ system was optimized and calculated by CALPHAD approach based on available phase diagram and relevant thermodynamic data of RE₂O₃-SiO₂（RE=Lu,Yb,Y） binary systems as well as our experimental data of Lu₂O₃-SiO₂ system obtained by quenching experiment. The Gibbs free energy of high temperature solution was described by an ionic two-sublattice model as(Lu³⁺)P(O^2-, SiO₂⁰)Q. The calculated phase diagram below 1873 K was in good agreement with experimental data at 1573, 1773 and 1873 K. The calculated Gibbs energies of two intermediate phases Lu₂SiO₅ and Lu₂Si₂O₇, the activity of Lu₂O₃ and SiO₂ and specific heat capacities of intermediate phases agreed well with experimental results of Y₂O₃-SiO₂ system. This tentative study will offer help for the research of single-phase phosphor and related metallurgical slags, refractories, high-temperature superconductivity material systems.

关键词：