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  • Enhancing the Interlaminar Shear Strength and Void Control of 3D-Printed Continuous Carbon-Fiber-Reinforced Polymer Composites Using a Robotic Magnetic Compaction Force-Assisted Additive Manufacturing (MCFA-AM) Process and Carbon-Nanofiber Z-Threads
Title: Enhancing the Interlaminar Shear Strength and Void Control of 3D-Printed Continuous Carbon-Fiber-Reinforced Polymer Composites Using a Robotic Magnetic Compaction Force-Assisted Additive Manufacturing (MCFA-AM) Process and Carbon-Nanofiber Z-Threads
Three-dimensional (3D) printing with continuous carbon-fiber-reinforced polymer (C-CFRP) composites is under increasing development, as it offers more versatility than traditional molding processes, such as the out-of-autoclave-vacuum bag only (OOA-VBO) process. However, due to the layer-by-layer deposition of materials, voids can form between the layers and weaken some of the parts’ properties, such as the interlaminar shear strength (ILSS). In this paper, a novel mold-less magnetic compaction force-assisted additive manufacturing (MCFA-AM) method was used to print carbon nanofiber (CNF) z-threaded CFRP (ZT-CFRP) laminates with significantly improved ILSS and reduced void content compared to traditional C-CFRP laminates, which are printed using a no-pressure 3D-printing process (similar to the fused-deposition-modeling process). The radial flow alignment (RFA) and resin-blending techniques were utilized to manufacture a printing-compatible fast-curing ZT-CFRP prepreg tape to act as the feedstock for a MCFA-AM printhead, which was mounted on a robotic arm. In terms of the ILSS, the MCFA-AM method coupled with ZT-CFRP nanomaterial technology significantly outperformed the C-CFRP made with both the traditional no-pressure 3D-printing process and the OOA-VBO molding process. Furthermore, the mold-less MCFA-AM process more than doubled the production speed of the OOA-VBO molding process. This demonstrates that through the integration of new nanomaterials and 3D-printing techniques, a paradigm shift in C-CFRP manufacturing with significantly better performance, versatility, agility, efficiency, and lower cost is achievable.  more » « less
Award ID(s):
2044513
PAR ID:
10482576
Author(s) / Creator(s):
; ; ;
Editor(s):
Manoj Gupta
Publisher / Repository:
MDPI
Date Published:
Journal Name:
Applied Sciences
Volume:
13
Issue:
10
ISSN:
2076-3417
Page Range / eLocation ID:
5914
Subject(s) / Keyword(s):
magnetic compaction force-assisted additive manufacturing (MCFA-AM) carbon-nanofiber z-threaded cfrp (ZT-CFRP) continuous carbon-fiber-reinforced polymer (C-CFRP) composite short-beam shear test interlaminar shear strength (ILSS) void compaction pressure fast-curing resin
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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