电渣重熔中TiO2对低氟CaF2-CaO-Al2O3-MgO-Li2O渣黏度和结构的影响  

Effect of TiO2 on Viscosity and Structure of Low-Fluoride CaF2-CaO-Al2O3-MgO-Li2O Slag for Electroslag Remelting

作　　者：巨建涛[1,2] 杨康帅 棘广恒 朱智洪 刘诗薇 Ju Jiantao;Yang Kangshuai;Ji Guangheng;Zhu Zhihong;Liu Shiwei(School of Metallurgical Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Research Center of Met-allurgical Engineering Technology of Shaanxi Province,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学冶金工程学院,陕西西安710055 [2]陕西省冶金工程技术研究中心,陕西西安710055

出　　处：《稀有金属材料与工程》2020年第11期3676-3682,共7页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(51774225,51704223)。

摘　　要：研究了连续冷却条件下电渣重熔中TiO2对低氟CaF2-CaO-Al2O3-MgO-Li2O渣黏度的影响,并利用傅里叶变换红外光谱和拉曼光谱分析水淬渣和对应结构的关系。结果表明,渣的黏度随着TiO2的增加而降低,当TiO2含量达到13.1%(质量分数,下同),随着温度从1743,1793,1843 K增加至1893 K时,对应黏度从0.067,0.059,0.056Pa·s降低到0.054 Pa·s;当温度达到1843 K或之上时,TiO2的加入对降低黏度有较小的影响。随着TiO2含量从0%,4.3%,8.7%增加至13.1%,黏流活化能从58.0,47.7,42.8 kJ/mol降低到38.6 kJ/mol。此外,傅里叶变换红外光谱表明,随着TiO2的加入,渣中[AlOnF4-n]-四面体络合物和[AlO4]-四面体网状结构被解聚,但没有发现[AlO6]-八面体结构;同时,拉曼光谱分析表明,TiO2加入可解聚[AlO4]-四面体网状结构中Al-O-Al键,并且Q4单元转化为Q2单元,同时形成O-Ti-O和Ti-O-Ti键。这些结果都表明TiO2可降低渣的聚合度,并且有利于渣的结构简单化。最终,黏度变化与渣的对应结构有很好的一致性。The effect of TiO2 on viscosity of low-fluoride CaF2-CaO-Al2O3-MgO-Li2O slag for electroslag remelting was investigated under continuous cooling conditions and the Fourier transform infrared(FTIR)and the Raman spectroscopy were employed to analyze the correction between the quenched slags and corresponding structure.Results show that the slag viscosity decreases with increasing the TiO2 content.At the TiO2 content up to 13.1 wt%,the corresponding viscosity values slowly decrease from 0.067,0.059,0.056 Pa·s to 0.054 Pa·s as the temperature increases from 1743,1793,1843 K to 1893 K and at higher temperature of 1843 K or above,TiO2 addition has a relatively small effect on lowering the slag viscosity.The calculated activation energy of viscous flow decreases from 58.0,47.7,42.8 kJ/mol to 38.6 kJ/mol with increasing the TiO2 content from 0 wt%,4.3 wt%,8.7 wt%to 13.1 wt%.Additionally,the FTIR results reveal that with the addition of TiO2,[AlOnF4-n]-tetrahedral complexes and[AlO4]-tetrahedral network structures depolymerize,but[AlO6]-octahedron is not found in the slag.Simultaneously,it can be seen from the Raman spectra that with the addition of TiO2,the depolymerization of the Al-O-Al linkage occurs in the[AlO4]-tetrahedral network structures,the part Q4 units transform to Q2 units and the O-Ti-O and Ti-O-Ti chains form.These results suggest that polymerization degree of these slags decreases with increasing the TiO2 content,which is beneficial to simplify slag structure.Finally,the changed slag structure is in good agreement with corresponding varying viscosity.

关 键 词：电渣重熔 低氟渣 傅里叶变换红外光谱 拉曼光谱 

分 类 号：TF14[冶金工程—冶金物理化学]