In‐Plane Tensile Damage and Failure Mechanisms of Open‐Hole Laminate due to Manufacturing Induced Triangular Gaps Defects

ABSTRACT Triangular gap is a common defect in the manufacturing process of carbon fiber reinforced plastic (CFRP). Triangular gaps have been observed at the same position as the drilling hole. Therefore, the coupling of triangular gaps and open‐hole is a situation worth studying. Both simulation and experiment are used to study the effect of the distribution of triangular gaps on the open‐hole laminate under in‐plane tensile load. The results indicate that the triangular gaps distributed along the longitudinal direction (tensile load direction) of the hole edge will not affect the open‐hole laminate, while the triangular gaps distributed along the transverse direction (perpendicular to tensile load direction) of the hole edge, that is, at the stress concentration area, will change fracture surface propagation direction from 45° to 90° and affect tensile strength of the open‐hole laminate. When triangular gaps are only distributed in the −45° plies, the maximum force decreases by 15.4%, and when distributed in all ±45° plies, the maximum force decreases by 21.6%. The experimental results confirmed the rationality of the finite element model, which can effectively predict the failure strength and failure modes. This study provides a basis for accurately evaluating the mechanical properties of composite materials with triangular gaps defects.