Magnesia carbon brick has the advantages of high temperature resistance, good slag resistance, strong thermal shock resistance, high thermal conductivity and low temperature creep, so it is widely used in steel production. In the ladle refining process, the erosion of slag-magnesium carbon bricks is usually the most severely damaged part of the lining. Its long-term chemical erosion and mechanical scouring of slag become its main damage mechanism, and the slag-line magnesia carbon brick Damage is an important factor affecting production efficiency and production costs. The wettability between slag and refractory is one of the important indicators to measure the resistance of refractory to slag erosion and penetration.
The scholars of Beijing University of Science and Technology used the drop method to determine the contact angle between solid and liquid, and studied the wettability between the two main components of the magnesium carbon substrate and the substrate and the LF refining slag, respectively. The mechanism of damage of magnesia carbon bricks was studied from a sexual perspective. Studies have shown that at the refining temperature, the slag is not wetted to the graphite, and the lower the temperature, the less likely it is to wet. The slag is completely wetted to the MgO component. The contact angle between the slag and the magnesium carbon substrate is significantly changed at a temperature of 1460 Celsius to 1480 Celsius. Below the turning point temperature, the reaction of MgO and carbon is suppressed, and the slag remains non-wetting to the substrate. Above the turning point temperature, MgO and carbon in the magnesium carbonaceous substrate react to form magnesium vapor and CO gas. This reaction results in a decrease in the carbon mass fraction in the substrate, and the contact angle of the slag to the substrate rapidly drops, eventually becoming completely wetted. When the contact angle between the slag and the substrate is less than 90, the slag will have a significant osmosis effect on the substrate. The pores formed by the reaction of MgO with carbon become the main channel for slag infiltration. When the slag penetrates into the unreacted layer inside the magnesium carbonaceous substrate, further penetration of the slag is hindered by the non-wetting property between the two and the less pores.