Axial Compression Performance of Carbon Fiber‐Reinforced Woven Thin‐Walled Tubes in Complex Environments: Effects of Temperature and Hydrothermal Aging

ABSTRACT The thin‐walled tubes of a fiber‐reinforced polymer composite material are affected by environmental factors such as high temperature and hydrothermal aging, which degrade the performance of the material. In this study, carbon fiber‐reinforced boron phenolic resin‐based (BPF) woven thin‐walled tubes (CFRPTs) with high fracture toughness were fabricated. The CFRPTs' service performance was tested at various temperatures (room temperature (RT), 90°C (T‐90), 270°C (T‐270), and T‐400 (400°C)) as well as subjected to hydrothermal aging (W‐60). The compressive strength, failure modes, and energy absorption characteristics were determined from axial compression tests. The results showed that the T‐270 exhibited the best compressive strength, with a value of 21 MPa, which was higher than that of the RT by 118%. The mechanical properties were degraded for the W‐60, which were 72% lower than those of the RT. The modified Fickian model predicted the moisture absorption rate better than the conventional Fickian model. Microscopic observations revealed that the interface bonding between the fibers and resin matrix was altered with changes in the environment. Temperature resulted in a change in the failure mode. The specific energy absorption ( SEA ) was affected by the changes in the state and mass of the BPF matrix. The T‐400 showed better energy absorption ( EA ) where the SEA , mean crushing force ( MCF ), and crushing force efficiency ( CFE ) were 0.6 J/kg, 2.3 kN, and 48%, respectively. Although the SEA was the lowest for the W‐60, its CFE was the highest, which was higher than that of the RT by 109%.