Microstructure, mechanical property and slag corrosion resistance of (Al,Cr)2O3-Mg(Al,Cr)2O4-Ca(Al,Cr)12O19 composite refractory using alumina-chromia slag

Abstract

Alumina-chromia/aluminum-chromium/(AC) slag, is basically treated as hazardous solid waste. The present work reports the preparation of (Al,Cr)2O3-Mg(Al,Cr)2O4-Ca(Al,Cr)12O19 composite refractory which is directly applicable to AC slag using reactive MgO as binder. Microstructure, mechanical properties and slag corrosion resistance to CaO-Al2O3-Fe2O3-SiO2-based slag of the prepared composite refractory were investigated. The results indicated that the obtained composites using AC slag aggregates exhibit superior corrosion resistance against the CaO-Al2O3-Fe2O3-SiO2-based slag compared with those with both AC slag aggregates and powders. Composites prepared using AC slag aggregates bonded with 5 wt% reactive MgO exhibited sufficient mechanical properties. This makes AC slag aggregates a possible candidate to prepare (Al,Cr)2O3-Mg(Al,Cr)2O4- Ca(Al,Cr)12O19 composite refractory used in iron- and steel-making process.