Sintering behavior of porous wall tile bodies during fast single-firing process

Abstract

In ceramic wall tile processing, fast single-firing cycles have been widely used. In this investigation a fast single-firing porous wall tile mixture was prepared using raw materials from the North Fluminense region. Specimens were obtained by uniaxial pressing and sintered in air at various temperatures (1080 -1200 °C) using a fast-firing cycle (60 minutes). Evolution of the microstructure was followed by XRD and SEM. The results revealed that the main phases formed during the sintering step are anorthite, gehlenite and hematite. It appears that the sintering process is characterized by the presence of a small amount of a liquid phase below 1140 °C. As a result, the microstructure of the ceramic bodies showed a network of small dense zones interconnected with a porous phase. In addition, the strength of the material below 1140 °C appeared to be related to the type and quantity of crystalline phases in the sintered bodies.

Porous Ceramic Supports for Membranes Prepared from Kaolin (DD3) and Calcite Mixtures

“…This reaction sequence and the reduced liquid phase formation improve the ceramic bodies with porosity and a wider ring range [36]. The increase in APS is also conrmed by SEM micrographs illustrated in Fig.…”

A Technological Study of the Elamite Polychrome Glazed Bricks at Susa, South‐Western Iran

“…The results show that the thermal profiles of the S.13 and S.76 bodies are quite similar. The initial loss of weight that occurred below 100°C can be attributed to the moisture content of the samples prior to analysis (Sousa and de Holanda ). In the case of the S.12 body, an endothermic peak corresponding to the decomposition of gypsum was observed at about 160°C and an endothermic peak that can be attributed to the dehydroxylation of clay minerals occurred at about 680°C (Papadopoulou et al .…”

Thermal conductivity and specific heat of kaolinite: Evolution with thermal treatment

“…6,7 As a consequence studies have been made to understand how different source clays lead to variation in properties such as shrinkage, frost resistance, water absorption or mechanical strength. [8][9][10][11] In contrast detailed knowledge of the thermal properties of clays, namely specific heat and thermal conductivity, is not complete. The specific heat of different source clays has been measured at low temperature, that is between 20 K and 600 K, and before any thermal treatment.…”