Mechanical Properties and Thermal Oxygen Corrosion Behavior of Al₂O₃f-CF Hybrid Fiber Reinforced Ceramicizable Phenolic Resin Matrix Composites

Oxidation at high temperatures impairs the properties of carbon fiber, limiting its application in thermal protection materials. In this work, alumina fiber hybrid carbon fiber reinforcements (Al₂O₃f-CF) were designed to improve the high-temperature oxidation resistance of carbon fiber, and Al₂O₃f-CF hybrid fiber reinforced ceramicizable phenolic resin matrix composites (ACFRP) were prepared to investigate thermal stability, mechanical properties, ablation resistance, and interface evolution at high temperatures. The results showed that after being treated at 1600 ℃ for 10 min, the flexural strength reached 43.74 MPa, which increased by 98.1%. The linear ablation rate and mass ablation rate of ACFRP were 0.06 mm/s and 0.056 g/s, respectively. The interface analysis showed that the coating of alumina fiber protected the carbon fiber well at high temperatures. Fiber hybrid provides a simple and effective method to improve the high-temperature oxidation resistance of carbon fiber.