摘要
为获得适用于高拉速薄板坯生产的高结晶高润滑性保护渣组分范围,综合旋转黏度计、四探针法电导率测定仪、半球点熔点仪、X射线衍射分析仪,研究碱度和BaO质量分数对保护渣理化性能的影响规律。试验结果表明,保护渣碱度提高,熔点、转折温度、开始析晶温度、析晶比例均呈现先降低后升高的规律,而高温黏度变化较小,其中,转折温度和析晶比例分别在碱度为1.65和1.55时达到最低值;析晶矿相中枪晶石Ca_(4)Si_(2)O_(7)F_(2)矿相析出量减少,Ca_(5)MgSi_(3)O_(12)和CaF_(2)矿相析出量增加。当碱度相同时,保护渣中BaO质量分数增加,熔点略微降低;高温黏度呈现小幅波动;转折温度先降低后升高,在BaO质量分数为6%时最低;开始析晶温度降低,且开始析晶温度越来越接近转折温度。综合而言,碱度为1.65、BaO质量分数为6%的保护渣最有利于润滑和传热的协调控制。
In order to obtain the composition range of mold fluxes with high crystallization and high lubrication,which is suitable for the production of thin slab with high speed,the effects of basicity and BaO content on physicochemical properties of mold fluxes were studied by combining rotating viscosimeter,four-probe conductivity tester,hemisphere point melting point tester and X-ray diffraction analyzer.The results show that,when the basicity of mold fluxes increases,the melting point,breaking temperature,initial crystallization temperature and crystallization ratio all decrease first and then increase,while the high temperature viscosity changes little.The breaking temperature and crystallization ratio reach the lowest values when the basicity is 1.65 and 1.55,respectively.The precipitation of cuspidine Ca_(4)Si_(2)O_(7)F_(2) decreases,while that of Ca_(5)MgSi_(3)O_(12) and CaF_(2) phases increases.When the BaO content increases in mold fluxes with the same basicity,the melting point decreases and the high temperature viscosity fluctuates slightly,while the breaking temperature decreases first and then increases with the valley corresponding to 6%BaO(mass fraction).In addition,the initial crystallization temperature decreases,and closed to breaking temperature gradually.Overall,the mold flux with basicity of 1.65 and BaO(mass fraction)of 6%is most conductive to the coordinated control of lubrication and heat transfer.
作者
严立新
邓必荣
罗钢
齐江华
梁亮
吴婷
YAN Lixin;DENG Birong;LUO Gang;QI Jianghua;LIANG Liang;WU Ting(Valin Lianyuan Iron and Steel Co.,Ltd.,Loudi 417000,Hunan,China;School of Metallurgical Engineering,Anhui University of Technology,Maanshan 243032,Anhui,China)
出处
《连铸》
2023年第4期10-16,22,共8页
Continuous Casting
基金
国家自然科学基金资助项目(51804004)。
关键词
保护渣
碱度
BaO含量
润滑
传热
mold fluxes
basicity
BaO content
lubrication
heat transfer
