The thermal stability of the molten slag plays an extremely important role in the smooth production of the blast furnace. In this paper, the effects of basicity, Al₂O₃ content and MgO content on the thermal stability of the slag during heat fluctuations were investigated. The effect of slag basicity and composition on slag viscosity behavior was measured by the rotating cylinder method under the condition of heat fluctuation and constant temperature. The slag temperature and solid phase precipitation under thermal fluctuations were calculated. The effect of thermal fluctuations of the slag on viscosity was clarified. The results show that the specific heat capacity of the slag first decreases and then increases as the slag basicity increases, and it increases with the rise of Al₂O₃ as well as MgO. The average viscosity change rate of slag under fixed heat is much more pronounced than that of at a constant temperature with the variation of slag basicity as well as Al₂O₃, while it is inverse for the effect of MgO. When the slag heat is reduced, the change in slag basicity has the greatest effect on the slag temperature, followed by the Al₂O₃ content and MgO content. It indicates that MgO helps to maintain a stable slag temperature. Therefore, appropriately increasing the basicity of the slag, controlling a lower Al₂O₃ content and maintaining a suitable MgO content will help to improve the thermal stability of the slag.

熔渣的热稳定性对高炉的顺利生产起着极其重要的作用。本文研究了碱度、Al ₂ O ₃含量和MgO含量对热波动过程中渣热稳定性的影响。采用转筒法在热波动和恒温条件下测量渣碱度和成分对渣粘度行为的影响。计算了热波动下的炉渣温度和固相沉淀。澄清了炉渣的热波动对粘度的影响。结果表明，炉渣比热容随炉渣碱度的增加先减小后增大，并随Al的升高而增大。₂ O ₃以及MgO。随着炉渣碱度和Al ₂ O _{3 的}变化，炉渣在定热条件下的平均粘度变化率比恒温下要明显得多，而MgO的影响则相反。当炉渣热量降低时，炉渣碱度的变化对炉渣温度的影响最大，其次是Al ₂ O ₃含量和MgO含量。这表明 MgO 有助于保持稳定的炉渣温度。因此，适当提高炉渣的碱度，控制较低的Al ₂ O ₃含量，保持适宜的MgO含量，有利于提高炉渣的热稳定性。