Effect of Automated Fiber Placement Induced Gap Defects on Impact Response and Residual Performance of <scp>CFRP</scp>

ABSTRACT Tow‐deviation gap defects induced by automated fiber placement threaten the reliability of composite structures, yet their effects on impact response and residual performance remain under‐investigated. CFRP laminates containing rectangular gaps of 2, 4, and 6 mm and isosceles right‐triangular gaps with a height of 6 mm are investigated. Postimpact damage in compression‐after‐impact and flexure‐after‐impact specimens is characterized by X‐ray CT and ultrasonic C‐scanning, respectively. Gap configuration has limited influence on the global response at lower energies, but its effect becomes more evident at higher energies. Larger rectangular gaps are associated with greater delamination and more severe residual‐strength degradation. At the common impact energy of 30 J, residual flexural strengths of specimens with 4 and 6 mm rectangular gaps and 6 mm‐high triangular gaps decrease by 96.2%, 94.9%, and 84.2%, respectively, whereas reductions in residual compressive strength remain below 28%. Furthermore, the triangular gap with a nominal height of 6 mm generally exhibits less delamination and strength loss than the 6 mm rectangular gap. These findings clarify the combined influences of gap configuration, impact energy, and subsequent loading condition, providing quantitative guidance for defect‐tolerant design of composite.