An experimental procedure for measuring interlaminar shear strength and fracture toughness in composite laminates was proposed. The procedure was used to determine the interlaminar properties of a quasi-isotropic laminate of IM7/K3B thermoplastic composite that had undergone thermal or thermo-mechanical aging. A five-point bending device and the ENF fixture were used to determine the interlaminar shear strength and interlaminar toughness, respectively. The aging effects on these two properties of IM7/K3B under various aging conditions were evaluated. It was found that the aging effect on interlaminar toughness is similar to that on interlaminar shear strength.
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