Abstract: The non-reactive mold fluxes were designed by carrying out steel-slag interfacial reaction experiments. And the effects of MgO content on their melting characteristics, viscosity properties, crystallization properties and heat transfer of slag film were investigated by melting temperature instrument, rotary viscometer, single hot thermocouple and heat flux measurement apparatus. The melting point of experimental slags was within the range of 1060~1180℃, and it was increased by 20℃ with MgO mass content increasing 1% from 2% to 8%. While the MgO content increased from 2% to 8%, viscosity and viscous flow activation energy were reduced first, and then increased sharply after reached their bottom values at the MgO content of 6%. The fact that MgO content increasing restrained the crystallization property was beneficial to weaken the development of slag film. The maximum heat flux, average heat flux and characteristic time were enhanced with the increase of MgO content for the thickness and crystallization ratio of slag film both minished.

Key words: MgO, high Al steel, non-reactive mold flux, viscosity, melting point, heat transfer

摘要： 通过钢-渣界面反应实验设计了非反应性保护渣，并采用渣柱变形法、旋转粘度计、热丝法和渣膜热流模拟仪分别研究了MgO含量对其熔融特性、粘度特性、结晶特性及渣膜传热特性的影响. 结果表明，实验渣系半球点温度在1060~1180℃内，且在2%~8%内平均每增加1%的MgO半球点温度升高约20℃. 当MgO含量从2%增加到8%时，保护渣的粘度及粘流活化能均先下降而后陡然增大，转折点对应MgO含量为6%. 增加MgO含量，非反应性保护渣晶体析出的孕育时间延长，有利于减弱高铝钢浇铸过程中渣圈的发展. 随着MgO含量的增加，非反应性保护渣渣膜厚度减小、结晶率降低，渣膜传热特征时间、最大热流密度及平均热流密度均增大.

关键词: MgO, 高铝钢, 非反应性保护渣, 粘度, 熔点, 热流