On transverse strength prediction of unidirectional carbon fiber reinforced polymer composites at elevated temperatures

Unidirectional carbon fiber reinforced polymer composites have potential advantages in near-hot end parts of high-end equipment and their reliability at elevated temperatures is an important issue concerned by researchers. An analytical model of temperature-dependent transverse strength is proposed by considering the combined influence of stress concentration, residual thermal stress, and thermo-physical properties of the matrix, and their evolution with temperature. The model is validated by comparing with the previous model and available 10 groups of experimental results at elevated temperatures. The maximum deviations under transverse tension and compression are approximately 14.7% of T300/BMP350 composite at 523 K and 12.7% of ZT7H/QY9611 composite at 473 K respectively. Furthermore, the important factors including the stress concentration and residual thermal stress on the transverse strength are analyzed. This study provides a reliable approach to predicting the transverse strength of composites in high-temperature environments and has implications for secure assessment.