The Effect of Pre-Cyclic Thermal Loads on the Buckling Performance of Glass Fiber-Reinforced Polymer Composites Without Post-Curing Treatment: Experimental and Numerical Investigation

This study examines the impact of pre-cyclic thermal loading on the buckling performance of S2 glass fiber-reinforced polymer (GFRP) composites fabricated without post-curing treatment. Specimens were subjected to 500 thermal cycles between −30°C and +80°C to simulate demanding aerospace conditions. Mechanical characterization was performed through tensile, shear, and buckling tests, and the results were compared with those of non-cycled counterparts. Finite element simulations incorporating Hashin's damage criteria were used to further elucidate the effects of thermal cycling. The findings reveal that pre-cyclic thermal exposure leads to notable improvements in in-plane material properties and critical buckling load, as well as enhanced displacement at buckling failure. Damage analysis indicates that thermal cycling strengthens fiber-matrix bonding while reducing delamination and micro-buckling. These results suggest that controlled thermal cycling can act as a quasi-post-curing process and offer a practical approach to enhance the durability and performance of GFRP composites in aerospace applications.