Numerical and experimental analysis of the mechanical properties of T300/AG80 laminated composites at elevated temperatures

Abstract

Carbon fiber-reinforced resin-based composites (CFRPs), notably T300/AG80, are increasingly used in aerospace, automotive, and high-performance applications. However, their load-bearing and stiffness significantly deteriorate at elevated temperatures. A comprehensive understanding of their thermal stability, especially under stabilized high-temperature conditions relevant to sustained heat exposure, remains lacking. This study addresses these uncertainties by systematically measuring the temperature-dependent tensile properties in the 0° fiber direction of T300/AG80 composites across 25°C to 375°C. The experimental investigation focused on the 0° fiber orientation to capture the fiber-dominated tensile behavior, while the finite element model incorporated a laminate stacking sequence of 0°, +45°, $-$ 45°, and 90° plies to reflect the mechanical and thermal responses of realistic aerospace-grade layups. A dual-method approach combined testing with simulations to analyze thermal effects on mechanical response. Results show the material retains about 85% of its original tensile strength up to 100°C; above this, significant degradation occurs, with a 46% reduction in tensile strength observed at 300°C. These findings underscore the vulnerability of CFRPs to high temperatures and highlight the necessity for developing composites with improved high-temperature resistance. The model closely matched experimental data, accurately depicting damage mechanisms and allowing prediction of failure processes not directly observed in physical tests. This validated modeling approach provides a robust framework for anticipating performance loss and guiding the design of more durable CFRP structures for extreme environments. Ultimately, the insights gained advance the understanding of CFRP failure under heat, supporting the development of stable materials crucial for future industrial applications exposed to high temperatures.