The influence of steel slag on the service life of ladle refractory is mainly manifested in three aspects:
1) influence of slag alkalinity;
The alkalinity in slag, namely CaO/SiO2 ratio, reflects the corrosion of slag to different refractory materials, the viscosity of slag itself and the liquefaction temperature. These studies should be analyzed from the slag atlas. Due to the change of CaO/SiO2 in slag, the slag liquid volume, liquefaction temperature, slag viscosity and chemical composition change, and these changes interact with the ladle wall refractory to form a lower temperature liquid phase, which enters into the slag body, leading to the corrosion consumption of refractory.
2) influence of slag oxidizability;
At present, the refining ladle slag line is mainly composed of magnesia-carbon brick, which is easy to be oxidized and is greatly affected by the oxidizability of slag. The stronger the oxidizability of slag is, the easier it is to oxidize and corrode magnesia-carbon brick.
3) influence of slag viscosity.
The penetration depth of slag into refractory is inversely proportional to the square root of slag viscosity. Therefore, the slag viscosity decreases, leading to the increase of diffusion depth, that is, the slag viscosity decreases, which will thicken the refractory reactive metamorphic layer and lead to the increase of erosion. The refractoriness of the refractory layer infiltrated by slag decreases, the sintering density increases, and the thermal expansion performance difference between the refractory layer and the original layer increases.