Improvement of corrosion resistance of spinel-bonded castables to converter slag

Limited chemisorbed hydroxyl groups around the crystalline entity of gel-route spinel powder helped to create nanopores in castable to resist slag penetration. The retained nanodimensional spinel in fired castable firmly connected hibonite and corundum grains, developed several interfaces after initial stage of densification, and arrested the detrimental ions of slag. XRD, scanning electron microscope (SEM) with atomic force microscope (AFM) studies of the nanostructured spinel-bonded castables corroborated their better properties than similar kind bonded with preformed spinel. The performance of spinel with 90% alumina and the conventional in situ spinel-bonded castables were satisfactory whereas the coprecipitated spinel was not commendable.