Multi-criteria and CNN analysis of Al2O3/TiO2/egg shell/ATH ceramic fillers in glass fiber-epoxy composites

The increasing global demand for sustainable and high-performance composite materials has driven research into novel filler combinations that enhance thermal and mechanical properties while minimizing environmental impact. This study explores the synergistic effect of egg shell waste—a calcium-rich biofiller—combined with inorganic ceramic fillers (alumina, titania, and aluminum trihydrate) in glass fiber-reinforced epoxy hybrid composites. Unlike prior studies focusing on individual fillers, this unique blend offers multifunctional enhancements. The composites' physical, mechanical, and thermal properties were systematically analyzed across various filler proportions, revealing substantial performance improvements. The optimal composite (L7GEATAER) exhibited a density increase to 3015.84 kg/m 3 and a 25.4 % reduction in water absorption. Mechanical tests demonstrated significant enhancements, with flexural and tensile strengths increasing by 2.14 and 1.57 times, respectively, while the glass transition temperature improved by 8.92 %. These enhancements are attributed to superior interfacial bonding , reduced polymer chain mobility, and uniform stress distribution. Advanced analytical techniques, including deep learning-based convolutional neural network (CNN) analysis of SEM microstructures, confirmed refined filler dispersion and improved structural integrity. This research highlights the potential of integrating biowaste with inorganic fillers to develop high-performance, sustainable composites suitable for demanding aerospace, automotive, and construction applications. The findings provide a comprehensive framework for optimizing filler combinations to meet specific industrial requirements while promoting circular economy principles.