B_(2)O_(3)对帘线钢高碱度LF精炼渣助熔作用  

Melting effect of B_(2)O_(3) on high alkalinity LF refining slag of cord steel

作　　者：李小明[1] 谢昊峰 邢相栋[1] 马雨溦 张欣华 LI Xiaoming;XIE Haofeng;XING Xiangdong;MA Yuwei;ZHANG Xinhua(School of Metallurgical Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,Shaanxi,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

出　　处：《钢铁》2023年第7期80-88,共9页Iron and Steel

基　　金：国家自然科学基金资助项目(52074207)。

摘　　要：针对帘线钢高碱度LF精炼渣中添加萤石助熔易导致氟污染及设备腐蚀等问题,采用B_(2)O_(3)替代CaF2作为CaO-SiO_(2)-MgO-Al_(2)O_(3)精炼渣系的助熔剂。基于某钢厂帘线钢现行精炼渣组分,设计B_(2)O_(3)质量分数为0~10.0%的5组试验渣系,进行熔点熔速及黏度试验,以考察B_(2)O_(3)质量分数对高碱度无氟精炼渣熔化特征温度、黏度及黏流活化能的影响。利用FactSage软件模拟计算渣系高温平衡物相转变过程,并对试验渣系进行X射线衍射以及傅里叶红外光谱分析,以研究含硼无氟精炼渣的高温熔融物相演变规律。结果表明。随着B_(2)O_(3)助熔剂添加量增大,渣系熔化特征温度显著降低,同时B_(2)O_(3)可有效降低渣系黏度及黏流活化能,当其添加量(质量分数)为7.5%~10.0%时助熔效果最佳。未添加B_(2)O_(3)助熔剂的精炼渣系熔点为1423℃,精炼温度下的黏度为1.11 Pa·s;当B_(2)O_(3)添加量(质量分数)达10%时,渣系熔点降至1245℃,精炼温度下的黏度降至0.28 Pa·s,下降幅度分别为12.51%和74.77%。对B_(2)O_(3)助熔机理分析显示,随着B_(2)O_(3)添加量增大,渣系初始结晶相由最初的Ca_(3)Al_(2)O_(6)、Ca_(3)MgAl4O10转变为硼硅酸盐和硅酸盐结构,体系聚合度升高,同时由于渣中[BO_(3)]-简单平面三角结构单元的存在,降低了熔融渣流动过程中的黏滞阻力,渣系流动性得到改善。To address the problems of fluorine contamination and equipment corrosion caused by the addition of fluorspar flux to high alkalinity refining slag for cord steel,B_(2)O_(3) was used as a flux for CaO-SiO_(2)-MgO-Al_(2)O_(3) refining slag system instead of CaF2.Based on the current refining slag components of cord steel in a steel mill,five groups of experimental slag systems with B_(2)O_(3) mass percent ranging from 0 to 10%were designed to conduct melting point melting speed as well as viscosity tests to investigate the effect of B_(2)O_(3) content on the melting characteristic temperature,viscosity and viscous flow activation energy of high alkalinity fluorine-free refining slag.The equilibrium phase transition process of the slag system was simulated using FactSage software,and the experimental slag system was analyzed by X-ray diffraction and Fourier infrared spectroscopy to study the molten slag phase to reveal the phase evolution of the boron-containing fluorine-free refining slag system.The results show that:with the increase of B_(2)O_(3) addition,the melting temperature and viscosity of the slag system significantly reduced,while B_(2)O_(3) can effectively reduce the viscosity and viscous flow activation energy of the slag system,the best flux effect will be obtained when B_(2)O_(3) is added at 7.5%-10.0%.The refining slag melting point without B_(2)O_(3) flux is 1423℃and the viscosity at refining temperature is 1.11 Pa·s,when the B_(2)O_(3) flux is added to 10%,the slag melting point decreases to 1245℃and the viscosity at refining temperature decreases to 0.28 Pa·s,the decreases reach 12.51%and 74.77%respectively.The study on the mechanism of B_(2)O_(3) flux shows that with the increase of B_(2)O_(3) addition,the initial crystalline phase of the slag system changes from the initial Ca_(3)Al_(2)O_(6),Ca_(3)MgAl4O10 to borosilicate and silicate structures,and the polymerization of the system increases,while the fluidity of the slag system is improved due to the presence of[BO_(3)]-simple planar str

关 键 词：B_(2)O_(3)助熔剂 CaO基精炼渣 黏度 熔化特征温度 熔渣结构 

分 类 号：TF769.2[冶金工程—钢铁冶金]