Mechanical characterization of carbon fiber composite materials with different reinforcement and thickness cured in autoclave

This study quantifies the influence of fiber architecture and laminate areal weight on the tensile response of autoclave-cured carbon fiber reinforced polymer (CFRP) laminates. The materials used were high-strength unidirectional (UD) prepreg (150 g/m2) andtwo woven fabrics: plain (200 g/m2) and 2 × 2 twill (630 g/m2). All materials were co-cured at 130 °C and 6 bar. Tension tests were performed according to ISO 527-5 for UD and ISO 527-4 for woven laminates. Six samples were tested for each condition. Variability, normality andfailure modes were documented. The UD laminate achieved an ultimate strength of 4734 MPa, a modulus of 235 GPa anda strain at break of 2.01 %. The 630 g/m2 twill achieved an ultimate strength of 856 MPa, a modulus of 41 GPa anda strain at break of 2.62 %. The 200 g/m2 plain achieved an ultimate strength of 530 MPa, a modulus of 38 GPa anda strain at break of 1.31 %. Thus, 0° alignment dominates tensile performance. UD maximizes strength and stiffness, whereas 0/90 weaving trades strength and modulus for higher ductility. Among the fabrics, the heavier 2 × 2 twill outperforms the lighter plain. Unlike prior comparisons that confound resin systems or cure schedules, this work provides a homogeneous benchmark that links architecture and areal weight to strength, stiffness andfracture deformation. The results are statistically sound andthe failure modes are documented. These findings will guide the selection of unidirectional (UD) versus woven laminates for lightweight, tensile, load-bearing components in aerospace and automotive applications.