Molecular dynamics insights into temperature-dependent interfacial properties and failure behaviors of carbon fiber/epoxy composites

JJ Chen and B Li and BH Gu and BZ Sun, COMPOSITE STRUCTURES, 374, 119758 (2025).

DOI: 10.1016/j.compstruct.2025.119758

Understanding the temperature-dependent mechanical properties and failure mechanisms is essential for optimizing the design of aircraft structural components. This study investigates the interfacial properties and failure behaviors of carbon fiber/epoxy composites across a temperature range from 173 K to 453 K by employing experiments and molecular dynamics (MD) simulations. Macroscale analysis indicates that the flexural modulus and strength decrease by 88.16 % and 94.51 % in three-point bending tests conducted at 453 K compared with those at 173 K. At the mesoscale, fiber breakage and resin cracking are the dominant failure modes at low temperatures, whereas interfacial delamination becomes predominant at high temperatures. Nanoscale simulations reveal that temperature-induced damage accumulates progressively within the microstructure. The carbon fiber-epoxy resin interface is especially susceptible to delamination under high temperatures owing to enhanced molecular mobility and structural disorder. The microstructure exhibits increased instability under tensile loading, suggesting the potential initiation of cracks and subsequent failure in the tensile regions of macroscopic components.

Return to Publications page