Preparation of Fe-Diopside Matrix Composites from Iron Tailings and Fly Ash

Abstract

Iron-diopside matrix composites were prepared by using iron tailings, fly ash and iron powder as main raw materials. The samples with iron contents of 20%, 30%, 40% and 50% were investigated and compared with the basic ceramic which without iron addition. By using the methods of X-ray diffraction (XRD), scanning electron microscope (SEM), flexural strength test, the phase identification, microstructure and mechanical properties of samples were determined. The results show that the optimum addition amount of iron is 40%, under the sintering temperature1200°C and holding time 90min, the main phase of the samples is diopside, iron and a small amount of quartz. The morphology of diopside is found to be columnar crystals. The sample prepared under these conditions has the maximum flexural strength of 140MPa, which is 105.9% higher than that of the basic ceramic, with a density of 3.6g/cm3. A new method of preparing composites from solid wastes has been developed.