Degradation Behavior of MgO-Based Refractory by CaO-SiO2-Al2O3-MgO-TiO2 System Ladle Slags

To understand the effect of TiO 2 in CaO-SiO 2 -Al 2 O 3 -MgO-TiO 2 system ladle refining slags on the degradation of MgO-based refractories, laboratory experiments were carried out to study the dissolution behaviors of MgO refractories into the slags and the penetration behaviors of the slags into the refractories. It was found that adding TiO 2 (0 to 10 pct) increases the solubility of MgO in the slags, thus the dissolution of MgO refractories into the slags was enhanced by TiO 2 . Meanwhile, TiO 2 also influences the physical properties of the slags. With the increase of TiO 2 content, the viscosity and the surface tension of the slags decrease first and increase, and the contact angle between the slags and MgO refractory changes oppositely. The depth of slag penetration into the refractory increases first and then decreases as well. TiO 2 in refining slags is very likely to accelerate the degradation of MgO refractory, while suitable MgO content in the slags can weaken this effect of TiO 2 . Besides, a denser refractory material is also beneficial to resist the degradation of the refractory.