Title: Three-Point Bending of Tapered Composite Coupons and Structures for Weight-Saving

Authors: Pinhua Guo, Spencer Wing, Wenyue Hu, Alexander Li, Carina Xiaochen Li, Bo Jin

DOI: 10.33599/nasampe/c.22.0104

Abstract: Weight reduction has been a major goal for high-performance composite applications such as aerospace and automotive. This paper introduces a weight-saving carbon fiber reinforced polymer (CFRP) layup method to produce tapered components that are progressively thinner toward the edges. The tapered layup was achieved by symmetrically shifting plies away from the laminates’ centerlines. This tailorable control of component thickness variation can shift material towards the area that is under a larger load and strain, resulting in a higher strength-to-weight ratio geometry. We describe the manufacturing process of the tapered laminates from a thin bi-angle dry fabric with vacuum infusion techniques to produce void-free components. In addition, void-free tapered and constant-thickness tubes were fabricated using unidirectional prepregs to study the tapering method in a different structure. This paper summarizes the mechanical characterization of such tapered components and compares the tapered coupons’ performance against their constant-thickness counterparts under various loading scenarios. The characterization investigated the behaviors of each component set in three-point bending, tension, and open hole tension conditions. The results indicated that the tapered coupons were able to maintain an acceptable strength while providing significant weight reduction. In addition, the three-point bending tests further demonstrated the tapered structures’ feasibility by showing no delamination after the tests, which indicated the ply drop-offs created by ply shifting are negligible, and the thickness-varying surface with ply steps can be viewed as a homogenized face.

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Conference: CAMX 2022

Publication Date: 2022/10/17

SKU: TP22-0000000104

Pages: 12

Price: $24.00