Title: Fiber Patch Placement in Aerostructures: Investigation on Material Equivalency

Authors: Dimitrios Sikoutris, Florian Lenz, Herbert Weidinger, Henriette Morgenstern, Neven Majić

DOI: 10.33599/nasampe/s.22.0716

Abstract: Fiber Patch Placement is an advanced technology for automated fiber lay-up of geometrically complex composites and reinforcements. Patches are cut from a fiber reinforced tape and applied precisely on predetermined positions on a mold with a flexible patch gripper. The individual orientation of each patch along load paths opens new potential for automated fiber lay-up applications in aerospace. However, since the Fiber Patch Placement laminates uses discontinuous fibers, the question of material equivalency to classical laminates with continuous fibers arises. To investigate that question, a series of mechanical tests were conducted according to relevant aerospace testing standards. In screening characterization on unidirectional (UD) reinforced laminates, it can be shown that the stiffness of patched specimens is almost at level with continuously reinforced reference specimens. And although the static tensile strength shows a noticeable knockdown factor compared to a continuous fiber laminate, Fiber Patch Placement laminates feature design allowables based on open hole tension & compression, compressions after impact and bearing strength which are at level with the values of the conventional laminate. These results show the potential for Fiber Patch Placement to become a standard manufacturing technology for high performance aerospace composites while maintaining material equivalency.

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Conference: SAMPE 2022

Publication Date: 2022/05/23

SKU: TP22-0000000716

Pages: 15

Price: $30.00