Study of clay used in the production of red ceramic pottery on semi-arid Cearense, Brazil

ABSTRACT

Red ceramics are part of one of the sectors of ceramic materials that make up the formation of the civil construction complex. In Cariri region and in the rest of Brazil, this segment uses clay as the main source of raw material, which favors the appearance of micro, small and medium enterprises that produce most of the products manufactured by the red ceramic sector. The objective of this work was the mineralogical and technological characterization of a clay sample from one of the potteries in Cariri region, intended for the manufacture of products to be used in civil construction such as tiles and bricks. For that, the techniques of X-ray fluorescence and X-ray diffraction were used, in addition to determining the physical-mechanical properties of the specimens by 4 ton-force uniaxial pressing followed by firing at 800, 900 and 1000ºC. The results showed that the sample is composed of quartz, kaolinite, smectite and muscovite and that it has granulometry mostly in fine fractions; after firing the clay shows reddish color and the Atterberg limits are within the range indicated for use on red ceramics. The clay under study has technological properties suitable for manufacture and the specimens burned at 800°C do not meet the values indicated by the literature. The studied clay proved to be suitable for application in tiles and perforated bricks.

Keywords
Red ceramics; Clay; Cariri region