Optimization of binder phase in mullit refractories

In this thesis, effect of the binder phase optimization study on therefractory properties of the mullite refractories was investigated. Twodifferent types of stage grain (sinter and fused mullite) and two differenttypes of binder matrix composition (quartz/alumina and kaolin/alumina)were used to produce test samples. 12 different refractory samplecompositions were prepared by adding different amount of ZrSiO4 to thedifferent binder matrixes. Behaviour of the samples against to thermal,mechanical and chemical loads was observed by applying standard testmethods. After the selection of binder raw materials on the basis of purity,mineralogical structure, reaction capacity and sintering activity, ZrSiO4addition to binder matrix increased the strength, creep resistance andcorrosion resistance. However, decrease in the thermal shock behavior wasobserved. It was concluded that increased sintering activity by ZrSiO4addition to the binder matrix plays an important role in the change ofrefractory properties. Properties of the samples prepared by different type ofstage grains and binder matrix were presented. Properties that are changingin broad limits are discussed on the basis of refractory applications.Keywords: Refractories, mullite, binder matrix, optimization, zircon.ii