Fabrication of economical refractory ceramics via local clay characterization and multi-response process optimization

Abstract This study establishes a robust framework for fabricating high-performance refractory ceramics from locally sourced Ethiopian kaolinitic clay through a multi-response optimization approach. Comprehensive characterization confirmed the clay’s high alumina-silica composition, establishing its fundamental suitability for refractory applications. An integrated Taguchi-Grey Relational Analysis (GRA) methodology was employed to optimize key processing parameters, including firing temperature, binder content, and calcination time. Statistical analysis of variance (ANOVA) identified binder content and calcination time as the most statistically significant factors influencing the final properties. The optimal processing conditions yielded a refractory material with exceptional mechanical strength, significantly reduced porosity, and enhanced densification. Microstructural analysis confirmed that these improvements resulted from a well-sintered ceramic body with prominent mullite crystallization. The model’s predictive accuracy was successfully validated, demonstrating its reliability for process optimization. This research provides a viable, data-driven strategy for developing industrial-grade refractories from indigenous materials, offering a sustainable alternative to imported products and supporting regional industrial self-sufficiency.