The potential of a method for the synthesis of ceramic-cementitious materials processed by an alternative route

Formulations of thermochemically bonded ceramics based of silicoaluminate raw materials were characterized. The mixtures were prepared using low water:solid and these were pressed under up to 30MPa. The specimens were cured for 2 hours at 200°C and were further characterized. The flexural strength registered 6.9-15.7 MPa, which was higher than common cements conventionally processed. The microstructures were dense, suggesting a favorable response of the mixtures to the activation process. The flexural strength varied with the type and amount of mixed raw materials. X-ray diffraction indicated that the crystalline phases from the raw materials did not react; the formation of zeolites was not observed.  The proposed processing is promising in order to obtain high strength in short curing times.

Keywords:geopolymers; ceramics chemically bound; activated clays; precast products.