Title: Automated Fiber Placement Defects: Insertion and Post-Cure Assessment

Authors: Roudy Wehbe, Addis Tessema, Ramy Harik, Brian Tatting, Addis Kidane, Zafer Gürdal

DOI: 10.33599/nasampe/s.21.0571

Abstract: Automated Fiber Placement (AFP) is a process used to manufacture advanced composite structures in the aerospace industry. The occurrence of defects during the layup process is a major drawback for AFP. Often, inspection and corrective measures are needed to meet specifications. These corrective measures are typically time consuming and prone to human error. A better understanding of the effect of AFP defects is essential for appropriate analysis. To achieve that, typical AFP defects have to be reproduced and studied through both experiments and numerical simulations. This paper aims to: (1) propose best practices on how to intentionally insert AFP defects in laminates, and (2) quantify their post-cure persistence through microscopic imaging. The focus is on four primary defects that predominately occur during AFP: gaps, overlaps, twists, and wrinkles. These defects are intentionally inserted at precise locations in laminae oriented at 0°, 90°, and ±45°. A step by step procedure is developed for the manual defect insertion as an effort to standardize the manufacturing process. Several composite panels are produced using the proposed techniques. The persistence of these defects can be depicted through magnified images captured using a microscope. These images can be used for accurate modeling of the post-cure shape of defects, which is necessary for future numerical simulation studies.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000571

Pages: 11

Price: FREE