Evaluation of Phyllite and Sand in the Heavy Clay Body Composition

Abstract

In this study the objective was to evaluate the properties affected by the incorporation of phyllite and sand as raw materials in the composition of ceramic material for the roofing tiles production with light color using kaolinite clay from Campos dos Goytacazes – RJ, Brazil as main raw material. Specimens were prepared by uniaxial pressing at 20 MPa and fired at 950oC. The determined technological properties were: dry apparent density, linear shrinkage, water absorption and mechanical strength (three point bend test). The results indicated that the incorporation of sand and phyllite improved the dry apparent density, reduced loss on ignition and aluminum oxide content of the pure clay. These factors resulted in a reduced open porosity, improving water absorption and linear shrinkage. However, the mechanical strength was compromised due to the increase of quartz content.