Effect of stabilizer and binder on the phase formation in zirconia castables for application in secondary steel industry

In the recent years, the demand for clean steel in critical applications e.g. in construction or transportation industry has increased. In view of the research and developments in the steel production and refinement it seems logical to pursue new approaches on the refractories and to evaluate the existing ones. Within this study zirconia castables stabilized by yttria or magnesia with additions of an alumina or an alumina-magnesia based binder were developed. The influence stabilizer and binder type on the phase evolution of the zirconia castables was investigated. The physical, mechanical and thermomechanical properties were evaluated. Subsequently, the zirconia castables were tested in a steel casting simulator under industry-oriented conditions. Alterations in surface chemistry and morphology were studied via optical light and scanning electron microscopy. Using an automated feature analysis, the solidified steel was investigated regarding the formation of non-metallic inclusions during steel casting experiments to identify their type and frequency.