Experimental and Computational Investigation of Fiber‐Matrix Interactions in Glass Fiber/ <scp>PA6</scp> / <scp>HDPE</scp> Tertiary Composites for Low Load‐Bearing Applications

ABSTRACT In this study, PA6/HDPE‐based polymer blends reinforced with varying glass fiber (GF) contents were developed to enhance mechanical and thermomechanical performance for structural applications. The work was conducted in two phases: Fabrication of PA6/HDPE blends and development of PA6/HDPE/GF composites. HDPE‐g‐MAH served as a compatibilizer, improving interfacial adhesion between immiscible phases, as confirmed by FTIR and SEM analyses. Among the blends, 70% PA6/30% HDPE showed the most balanced properties and was selected as the base matrix. Incorporation of 5 wt% GF (P65H30GF5) achieved optimal impact strength (~41 kJ/m 2 ) and hardness (~91 HRB), whereas higher GF loading increased stiffness but reduced toughness due to brittleness and fiber agglomeration. Thermal analysis (DSC&amp;TGA) confirmed enhanced stability and degradation resistance. Finite Element Analysis (FEA) was performed to evaluate the tensile behavior and stress distribution of GF/PA6/HDPE composites. The simulation revealed uniform deformation and a systematic increase in von Mises stress, displacement, and reaction force with higher glass fiber content, confirming improved stiffness and load‐bearing capability consistent with experimental observations. Overall, the optimized PA6/HDPE/GF composites exhibit a promising combination of rigidity, dimensional stability, and thermal resistance, making them suitable candidates for low load‐bearing structural components in automotive interiors, appliance housings, and lightweight industrial applications.