Geopolymer-based ceramics are composed of aluminosilicate raw materials that can undergo polymerization reactions using alkaline activators and transform into ceramics following heat treatment in the 800 to 1200°C range. During this process, the initial amorphous structure transforms into ceramic crystalline phases, thereby reducing porosity and increasing the density of the component. Four main categories of raw materials are used to prepare ceramized geopolymers: (1) natural aluminosilicates (basalt, volcanic ash, kaolin, metakaolin, and illitic clay), (2) industrial wastes (fly ash, blast furnace and steel slags, and ceramic waste), (3) additives (waste glass powder, and basalt fibers), and (4) alkaline activators (sodium and potassium hydroxides, silicates, and sodium aluminate). Based on prior research, an analysis was conducted utilizing the oxide compositions of the raw materials to predict the behavior of the geopolymer-based ceramic, an approach that has not previously been undertaken by others.

The findings indicated that the dominant ceramicization mechanism could be predicted by considering the SiO₂/Al₂O₃ and (CaO+MgO)/SiO₂ ratios. For instance, metakaolin (with an SiO₂/Al₂O₃ ratio of approximately 1.9) achieves a compressive strength of up to 95 MPa through the crystallization of N-A-S-H gel, whereas blast furnace slag (containing approximately 40% CaO) allows for sintering at temperatures between 800°C and 950°C via the formation of the C-A-S-H phase.

Four primary mechanisms of ceramization were identified and elucidated: the formation of N-A-S-H versus C-A-S-H gels, viscous flow sintering, the crystallization of ceramic phases (leucite, mullite, cordierite), and the self-healing of the glassy phase, which reduces open porosity to less than 1%.