Effect of ferrotitanium slag particle size on properties of Al2O3–SiC–C castables

• Published in: Ceramics international Vol. 50; no. 20; pp. 38896 - 38903
• Main Authors: Zhang, Xifei, Long, Tu, Chen, Ding, Gu, Huazhi, Zhang, Meijie, Huang, Ao, Fu, Lvping, Zou, Yongshun, Li, Libei, Zhang, Jiaqin, Qiu, Wendong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.10.2024
• Subjects: Al2O3–SiC–C castables; Ferrotitanium slag; Mechanical properties; Particle size; Slag resistance; Ferrotitanium slag; Mechanical properties; Particle size; Al2O3–SiC–C castables; Slag resistance
• ISSN: 0272-8842
• DOI: 10.1016/j.ceramint.2024.07.252

Ferrotitanium slag can be used to replace bauxite to fabricate refractories owing to its high refractoriness (>1790 °C) and Al2O3 content (≥70 wt%). However, impurities in the ferrotitanium slag is harmful to the materials. In this paper, the mechanical properties and molten slag resistance of Al2O3–SiC–C castables were improved by replacing part of bauxite with large size ferrotitanium slag (8-5 mm). The large size ferrotitanium slag contained a small amount of impurities, which reacted with SiO2 at high temperature to form CaO–Al2O3–SiO2–TiO2 liquid layer on the surface of particles. Under the action of the liquid phase, the ferrotitanium slag particles and the matrix were combined more closely. With the decrease of the particle size of ferrotitanium slag, the slag resistance of the castables began to decrease. This was because the specific surface area of the particles with smaller particle size was relatively larger, large contact area with molten slag resulted in worse slag resistance. Meanwhile, decreasing ferrotitanium slag particle size brought the increase of apparent porosity of Al2O3–SiC–C castables, resulting in weak mechanical properties.