Damage progression and notched strength recovery of fiber-reinforced polymers encompassing self-healing of interfacial debonding

Abstract

This study examines the interfacial debonding behavior of self-healing fiber-reinforced polymers and the performance of repair of interfacial debonding. Self-healing is accomplished by incorporating a microencapsulated healing agent and a catalyst within a coating layer on the surface of the fiber strand. Single edge-notched tensile specimens of unidirectional fiber-reinforced polymers with coated fiber strands were prepared and tested. The healing efficiency was evaluated by the critical fracture loads of virgin and healed specimens. To investigate the release of the healing agent from microcapsules during interfacial debonding, an ultraviolet fluorescent dye was added to the healing agent, and post-fracture specimens were examined by an optical microscope under ultraviolet light. In addition to conducting experiments, finite-element analyses were performed using a three-dimensional model to predict the damage progression in single edge-notched tensile specimens.