Title: Effect of Gaps on the Damage Initiation and Failure of Thin Composite Laminates Manufactured by AFP Under Out-of-Plane Loading

Authors: Mohammadhossein Ghayour, Mehdi Hojjati and Rajamohan Ganesan

DOI: 10.33599/nasampe/s.20.0172

Abstract: Advanced robotics as one of the elements of the smart factory has attracted interests in the composite industry through the last decade, and Automated Fiber Placement has found its way to be one of the well-established composite fabrication techniques in both aerospace and automated industries. However, because of using the fiber tows instead of composite prepreg sheets, new types of defects may be formed during the fiber deposition by a robot arm. These defects can induce interlaminar/intralaminar damages under the service loading, which reduces the mechanical performance of the final products. Although the effect of these defects on the performance of the composite structure can be found in the literature, there is still a lack of knowledge in the mechanism of interaction between the manufacturing defects and damages. In the present study, the effect of automated manufacturing gaps on the damage initiation and propagation in Carbon/Epoxy composite beams under out-of-plane loading is investigated. Short beam shear and three-point bending tests are carried out on the samples with defects. Flexural and interlaminar shear strengths of the samples are measured and compared with the samples with no defects (baseline sample). Furthermore, a series of microscopic observations are performed, and the effect of the manufacturing defects on the delamination and matrix damages initiation and also on matrix cracks propagation is investigated.

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Conference: SAMPE 2020 | Virtual Series

Publication Date: 2020/06/01

SKU: TP20-0000000172

Pages: 9

Price: FREE