Flux ceramic tiles based on Egyptian trachyte

Abstract

Background

The present title is aiming to study the effects of trachyte additions on the sinterability of the ceramic tiles. Four batches were designed with different trachyte/clay ratios from 10 to 40% and 3% of bentonite.

Results

Chemical and phase composition of the raw materials were investigated using XRF and XRD techniques as well as petrographic examination. The prepared batches were fired from 1140 to 1280 °C, their densification parameters and phase compositions as well as microstructure were investigated. Petrographically, the studied trachytic rocks are fine to medium grained, grayish to dark gray, massive rocks, built up, essentially, of alkali feldspars phenocrysts, mainly sanidine and albite, with less frequent pyroxenes and amphiboles, held together in fine to very fine-grained groundmass. The XRD patterns of the fired batches exhibited mullite and quartz as the main mineral phases.

Conclusions

The densification parameters declared that by rising temperature, the bulk density increased in batches of lower trachyte contents and apparent porosity decreased, while in batches of higher trachyte contents exhibited slight increase. It is evident that the main factors controlling the formation present mullite crystallization are: (A) trachyte/clay content which, consequently, affects the Al₂O₃/SiO₂, (B) alkali contents and (C) firing temperature.