Glass fiber composites are widely used in industries due to their cost-effectiveness and thermal insulation properties despite being less performant than carbon fiber composites. Enhancing glass fiber composites’ thermal and mechanical properties is beneficial when alternatives are lacking. This paper reports useful optimization results using Yttria-Stabilized Zirconia (YSZ) nano-additives in E-Glass Fabric Composites (GFC) to improve these properties and underlying mechanisms. The composite’s combined thermo-mechanical optimization is reported for the first time. The study determined that incorporating optimally (3wt%) nano-YSZ into the thermoset matrix phase and then infusing it into the GFC system through optimized processing parameters significantly enhances compressive residual strain and also the compressive, tensile and flexural strengths and fracture toughness. Key findings include a 12.3% increase in thermal stability over a temperature range of 25–100 °C and improvements in interfacial adhesion and interfacial crack inhibition, resulting in a 75% increase in storage modulus and a 40% enhancement in mode-I fracture toughness in the YSZ-matrix that translated to a 9% increase in the YSZ-Glass fabric interface. Additionally, mode-II fracture toughness increased by 18%, and the mode-II to mode-I fracture toughness ratio, indicating interlaminar strength enhancement, was superior to other types of ceramic additives used in GFCs at higher concentrations. Flexural stiffness and strength increased by 30% and 94%, respectively, at 100 °C due to the nano-scale effects and fiber-matrix interface interactions. This optimization demonstrates that a dilute nano-ceramic dispersion can significantly improve the performance of lightweight, multifunctional composites in thermo-structural applications such as aerospace, automotive, microwave transparent structures, and electronic packaging.
