Refractory Materials in Continuous Basalt Fiber Production: Melt Interaction, Corrosion Behaviour, and Industrial Experience

This paper examines the physicochemical and operational factors governing the behaviour of refractory materials in contact with basalt melts during continuous basalt fiber production. Published studies of refractory corrosion are considered alongside comparative dynamic tests of three industrial refractory specimens: a mullite–corundum material (R1), a high-chromia material (R2), and a fused-cast alumina material (R3). Cylindrical rods, 20 mm in diameter, were exposed to a melt prepared from basalt of the Berestovets deposit at 1450 °C for 3 h, with an immersion depth of 40 mm and rotation at 20 rpm. Based on ten microscopic measurements for each material, the mean depths of the altered contact zones were approximately 1.20, 0.22, and 0.20 mm, respectively. R1 exhibited local cavities reaching 3.0–3.5 mm; R2 showed a pronounced surface layer, whereas R3 exhibited a comparatively distinct contact boundary. Industrial cases of lining failure are discussed, including deep melt penetration into a defective batch of mullite–corundum blocks. Two complementary conceptual relationships are proposed: a functional representation of factors governing service resistance and a phenomenological balance of material loss. The measured depth of the altered zone is distinguished from infiltration, actual material loss, and mechanical serviceability. The proposed models require quantitative validation.