A novel and effective approach to improve the oxidation resistance and slag corrosion resistance of Al2O3–SiC–C castables

Abstract

The present study aims to clarify the role of ball pitch in Al2O3–SiC–C (ASC) refractory castables and investigate the influence of low temperature treatment on the composition, microstructural evolution, and properties of ASC refractory castables. By utilizing the expansion properties of ball pitch during heating, the castables undergo a low temperature treatment to induce the flow and expansion of ball pitch within the castables. This, in turn, fills the surrounding pores and enhances the physical properties of the castables. The results of this study demonstrate that low-temperature heat treatment of the castables at temperatures at 350 °C significantly improves the hot modulus of rupture, oxidation resistance, and slag resistance after sintering. This improvement is attributed to the optimized microstructure. In comparison to the corresponding samples without low temperature treatment, the high temperature modulus of rupture (HMOR) of the calcined castables treated at 350 °C increases by 33.3%. Additionally, the oxidation index and slag corrosion index after sintering at 1500 °C decrease by 39.6% and 87.31% respectively for the samples low temperature treated at 350 °C, as compared to the samples low temperature treated at 110 °C. This study provides a fresh perspective on the production of ASC castables with exceptional high temperature performance.