All-Solid-Waste-Derived High-Temperature Ceramic Glazes Enable Mechanism-Informed Sustainable Color and Texture Design via Phase–Microstructure Tuning

Glazes primarily utilize raw minerals like kaolinite. However, considering sustainable development, employing industrial solid waste offers greener design solutions and high economic efficiency. This study employs multiple analytical methods, including XRF, XRD, and SEM, to investigate the feasibility of replacing traditional glaze materials entirely with solid waste. It elucidates the mechanisms underlying changes in texture and color resulting from alterations in microstructure and chemical composition. Research on five different ratios of ceramic glaze composed of fly ash, blast furnace slag, silica fume, coal gangue, and desulfurization gypsum reveals that the implementation of solid waste-based glazes is feasible. The glazes formed a SiO2–Al2O3–CaO system surface, all exhibiting anorthite and diopside as the primary crystalline forms. The results are as follows: 1. The content of Ca and Mg depends on the overall proportion of elements, with a Ca threshold of approximately 28%. Below this threshold, characteristics such as surface roughness and porosity are observed. Above this threshold, as seen in G3 and G4, crystal distribution becomes more dense. 2. Si is the key factor controlling crystal variation. Sample G5 exhibits good crystal continuity. Visually, its color appears distinctly deep red. 3. Samples G1 and G2 both contain approximately 4.8 wt% Fe2O3, but G2 exhibits more crystalline precipitation. Visually, G2 appears more reddish-yellow than G1. Higher crystallinity yields superior coloration.