Chong Junkai, Shen Yingying, Yang Peng, Tian Jianke, Zhang Wenjuan, Tang Xingchang, Du Xueyan
School of Materials Science and Engineering, State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals, Lanzhou University of Technology, Lanzhou 730050, China.
Materials (Basel). 2020 Mar 8;13(5):1214. doi: 10.3390/ma13051214.
In order to reduce the amount of fluorite during the steelmaking process for environmental protection, it is essential to investigate the fluorine-free slag system. Thus, high-basicity CaO-SiO-FeO-MgO slag with BO content from 0% to 15% was designed, and its melting characteristics and viscosity were investigated. The influence of BO content on the phase diagram of the slag system was calculated using FactSage 7.3, and the break temperature was determined from the curves of temperature-dependent viscosity. The results show that, with the increase in BO content, the melting characteristics of the CaO-SiO-FeO-MgO/BO slag system, including liquidus temperature, flow temperature, softening temperature, and hemispheric temperature, all decreased; the main phase of the slag system transformed from CaSiO into borosilicate, and finally into borate; the viscous flow activation energy reduced from 690 kJ to 130 kJ; the break temperature reduced from 1590 °C to 1160 °C. Furthermore, the melting characteristics and the break temperature of the slag system with 5% and 8% BO content were found to be the closest to the values of fluorine-containing steel slag.
为了在炼钢过程中减少萤石用量以保护环境，研究无氟渣系至关重要。因此，设计了BO含量从0%到15%的高碱度CaO-SiO-FeO-MgO渣，并对其熔化特性和粘度进行了研究。使用FactSage 7.3计算了BO含量对渣系相图的影响，并从温度依赖性粘度曲线确定了转折温度。结果表明，随着BO含量的增加，CaO-SiO-FeO-MgO/BO渣系的熔化特性，包括液相线温度、流动温度、软化温度和半球温度均降低；渣系的主相从CaSiO转变为硼硅酸盐，最终转变为硼酸盐；粘性流动活化能从690 kJ降低到130 kJ；转折温度从1590℃降低到1160℃。此外，发现BO含量为5%和8%的渣系的熔化特性和转折温度与含氟钢渣的值最接近。
