Thermal Oxidative Stability of Fiber-Reinforced Polymer Matrix Composites

The thermal oxidative stability of aerospace grade fire retardant fiber composites is a critical factor determining their performance and durability in high-temperature and oxidative environments. These composites, commonly used in aircraft and spacecraft applications, are subjected to extreme conditions during operation, necessitating a thorough understanding of their thermal and oxidative degradation mechanisms. In the herein study, thermal oxidative stability of carbon and glass fiber-reinforced polymer composites was investigated by employing a combination of experimental techniques, including dynamic mechanical analysis, and isothermal aging in an air-circulating oven. the maximum aging temperature was selected based on the glass transition temperature of the specimens. The aged sample was removed at regular intervals (100h, 250h, 500h, 750h, and 1000h) and weight loss was recorded until the completion of 1000 hours. short beam shear (SBS) test was conducted on the composite samples to examine the impact of thermal aging on the mechanical properties of the materials under simulated operational conditions. The results demonstrated good thermal stability for both composite materials, evidenced by a glass transition temperature and a weight loss of less than 0.3%. Also, about 10% and 7% drop in interlaminar shear strength was observed in carbon and glass fiber composites, respectively. The outcomes of this research have significant implications for the design, manufacturing, and optimization of aerospace grade fire retardant fiber composites, ultimately contributing to improved safety, reliability, and performance in demanding aerospace applications.