Title: Direct Digital Manufacture of Continuous Fiber Reinforced Thermoplastic Composites Incorporating Reduced Tooling Requirements and Product Quality Feedback Control

Authors: Donald W. Radford and Harry Ratkai

DOI: 10.33599/nasampe/s.25.0270

Abstract: The development of automated placement and in-situ consolidation of high-volume fraction continuous fiber reinforced thermoplastic composites, using commingled tow feedstocks, offers a path to the manufacture of complex structural products with radically reduced tooling requirements. Reduced tooling needs can enable more rapid introduction of design alternatives. However, manufacturing process parameters are commonly determined by trial and error, resulting in a “best” processing schedule, in the hope that consistent, high-quality composites are produced. This approach to process parameter development for evolving part geometries can also reduce productivity. Equipment and manufacturing technologies will be discussed that allow structural composite products, including grid stiffened panels to be produced without the complex tooling usually employed to produce grid stiffeners and manage material build-up at stiffener intersections by consolidation force feedback control. In addition, preliminary results are presented demonstrating that tow width can be employed as a direct metric of composite grid stiffener quality and can be used in the real-time control of the automation system, with the goal of removing the need to follow a single, predetermined processing schedule. Thus, the combination of the automated positioning with in-situ consolidation and the implementation of a composite quality-based real-time feedback control approach, holds the potential to continuously tune the process parameters, representing an important step toward a future alternative to conventional composites processing

References: [1] F.C. Campbell, Structural composite materials. ASM International, 2010. ISBN:9781615031405. [2] S.M. Huybrechts, S.E. Hahn and T.E. Meink, Grid Stiffened Structures: A Survey of Fabrication, Analysis and Design Methods, ICCM/12, 1999. [3] M. Buragohain, and R. Velmurugan, Study of Filament Wound Grid-Stiffened Composite Cylindrical Structures, Composite Structures, Volume 93, Issue 2, 2011. DOI: 10.1016/j.compstruct.2010.06.003. [4] H. Ahmadi and G. Rahimi, Analytical and experimental investigation of transverse loading on grid stiffened composite panels, Compos. Part B Eng., vol. 159, pp. 184–198, Feb. 2019. DOI: 10.1016/j.compositesb.2018.09.040. [5] S. Shroff, E. Acar and C. Kassapoglou, Design, Analysis, Fabrication, and Testing of Composite Grid-Stiffened Panels For Aircraft Structures, Thin-Walled Struct., 2017. DOI: 10.1016/j.tws.2017.06.006. [6] S.M. Huybrechts, T.E. Meink, P.M. Wegner and J.M. Ganley, Manufacturing Theory for Advanced Grid Stiffened Structures, Composites Part A: Applied Science and Manufacturing 33.2, pp. 155-161, 2002. DOI: 10.1016/S1359-835X(01)00113-0. [7] Z. Qureshi, T. Swait, R. Scaife and H.M. El-Dessouky, In Situ Consolidation of Thermoplastic Prepreg Tape Using Automated Tape Placement Technology: Potential And Possibilities, Compos. Part B Eng., 2014. DOI: 10.1016/j.compositesb.2014.05.025. [8] H. Prusz and T. Vietor, Design for Fiber-Reinforced Additive Manufacturing, Journal of Mechanical Design, 2015, Vol.137(11), p.111409. DOI: 10.1115/1.4030993. [9] F. Van Der Klift, Y. Koga, A. Todoroki, M. Ueda, Y. Hirano, and R. Matsuzaki, 3D Printing of Continuous Carbon Fibre Reinforced Thermoplastic (CFRTP) Tensile Test Specimens, Open Journal of Composite Materials, January 5 2016: 18-27. DOI: 10.4236/ojcm.2016.61003. [10] K.M. Warlick and D.W. Radford, Combining Aspects of Additive Manufacture and Filament Winding to Produce Composites with Novel Fiber Reinforcement Patterns”, CAMX 2016 – Composites and Advanced Materials Expo., September 26, 2016. [11] P.A. Rodriguez, M.E. Bourgeois, and D.W. Radford, Direct Manufacture of Continuous Fiber Reinforced Composites through a Combination of Fiber Placement and 3D Printing”, CAMX 2016 – Composites and Advanced Materials Expo., September 26, 2016. [12] S.J. Hogan, and D.W. Radford, Direct Digital Manufacture of Continuous Fiber Reinforced Thermoplastic High Aspect Ratio Composite Grid Stiffeners with Radically Reduced Tooling, SAMPE Journal, Vol.59, No1, January/February 2023, pp.52-61. [13] S.J. Hogan, Direct Digital Manufacture of Continuous Fiber Reinforced Thermoplastic High Aspect Ratio Grid Stiffeners and Grid Stiffener Intersections with Radically Reduced Tooling, Master’s Thesis, Colorado State University, 2024. [14] H. Ratkai, S.S. Tanu, and D.W. Radford, Automated Manufacturing of Grid Stiffened Panels with Radically Reduced Tooling, CAMX 2023, Atlanta, GA, Oct. 31, 2023. DOI:10.33599/SJ.v60no1.03 [15] H. Ratkai, Direct Digital Manufacturing of Uniform Thickness Continuous Fiber Grid Stiffened Composites through Tow Spreading via Roller Based Deposition, Master’s Thesis, Colorado State University, 2024. [16] Ranjit K. Roy, A Primer on the Taguchi method, Society of Manufacturing Engineers, 2010. ISBN:9780872638648.

Conference: SAMPE 2025

Publication Date: 2025/05/19

SKU: TP25-0000000270

Pages: 16

Price: $32.00