Title: Heated Compression Testing to Reduce Calibration Costs in the Onboarding of Fiber-Reinforced Feedstocks for Large Area Additive Manufacturing Thermoplastic Extrusion

Authors: James C. Haller, Jr. & Jason S. Stevens

DOI: 10.33599/nasampe/c.25.168

Abstract: Large Area Additive Manufacturing (LAAM) has been an emerging area of interest in the composites industry, enabling the rapid prototyping and fabrication of structural components and systems. Increasingly larger platforms for LAAM extrusion have been developed for both research and development as well as commercial end-use purposes, with some available extruder capacities reaching up to 225 kg/hr and print bed platforms up to 29 m in length. Although similar in concepts to smaller scale thermoplastic extrusion equipment, the nuances associated with LAAM extrusion platforms present unique challenges, which are often particular to an individual piece of LAAM equipment. One of the primary challenges associated with LAAM extrusion methods includes the onboarding and calibration of fiber-reinforced feedstocks. Processing settings, such as screw speeds and material melt temperatures, are often found to be unique to a particular piece of extrusion equipment or bead geometry and are not easily translatable between disparate use cases. The University of Maine’s Advanced Structures and Composites Center has been developing methods to minimize time, effort, and material costs associated with the onboarding and calibrating of fiber-reinforced pellet feedstocks for LAAM thermoplastic extrusion. Compression testing, based on ASTM D695, of injection molded coupons was performed within a heated environmental chamber to determine maximum temperatures at which a LAAM extruded bead of the same material would retain loading capacity to self-support additional print layers. When combined with an on-tool infrared pyrometer to monitor deposition and substrate temperatures, reductions in costs associated with the non-value-added process of onboarding material feedstocks were observed. Initially performed using a pelletized PA12-glass fiber feedstock on a Cincinnati BAAM, work is currently underway to extend this process to LAAM extrusion efforts using other material systems.

References: [1] Shah, J., Snider, B., Clarke, T., Kozutsky, S., Lacki, M., & Hosseini, A. “Large-scale 3D printers for additive manufacturing: design considerations and challenges.” The International Journal of Advanced Manufacturing Technology 104 (2019): 3679-3693. DOI: 10.1007/s00170-019-04074-6 [2] Talabi, S. I., Chawla, K., Rodriguez, B., Barakat, A., Meraki, Y., Phadatare, A., Brander, M., Seta, B., Spangenberg, J., Wu, H. F., Vaidya, U., Kunc, V., Hassen, A. A., & Kumar, V. “Fiber orientation and porosity in large-format extrusion process: the role of processing parameters.” Composites: Part A 194 (2025): 108891. DOI: 10.1016/j.compositesa.2025.108891 [3] Bhandari, S., Lopez-Anido, R. A., Anderson, J., & Mann, A. “Large-scale extrusion-based 3D printing for highway culvert rehabilitation.” Proceedings of SPE ANTEC 2021L The Annual Technical Conference for Plastic Professionals. Held Online, May 10-21, 2021. Society of Plastics Engineers. Curran Associates, Inc. pp. 33-37. [4] Schweizer, K., Bhandari, S., Lopez-Anido, R. A., Korey, M., & Tekinalp, H. “Recyclying large-format 3D printed polymer composite formworks used for casting precast concrete – technical feasibility and challenges.” Journal of Composites for Construction 28(6) (2024): 04024061. DOI: 10.1061/JCCOF2.CCENG-4758 [5] Bhandari, S., Lopez-Anido, R. A., Saavedra Rojas, F., & Lebihan, A. “Design and Manufacture of Precast Concrete Formworks Using Polymer Extrusion-Based Large-Scale Additive Manufacturing and Postprocessing.” Progress in Additive Manufacturing 2021 (2022): 1-13. DOI: 10.1520/STP164420210120 [6] Saltonstall, P. “University of Maine: 3Dirigo – World’s largest 3D-printed boat.” Maine Boats. Saltonstall, P. Issue 162, January - February 2020. Accessed May 21, 2025. <https://maineboats.com/print/issue-162/university-maine-3dirigo> [7] Espinosa, S. “ERDC plays critical role in review of first 3D printed Army barracks.” February 24, 2025. U.S. Army Engineer Research and Development Center, Vicksburg, MS, USA. Accessed May 21, 2025. <https://www.erdc.usace.army.mil/DesktopModules/ArticleCS/ Print.aspx?PortalId=55&ModuleId=23804&Article=4075527> [8] Burke, J. “ORNL, UMaine 3D print home from biobased materials, develop blueprint for rapid manufacturing.” April 27, 2023. Oak Ridge National Laboratory, Oak Ridge, TN, USA. Accessed May 21, 2025. <https://www.ornl.gov/news/ornl-umaine-3d-print-home-biobasedmaterials-develop-blueprint-rapid-manufacturing> Study.” [9] Liedtka, C. “Life Cycle Analysis and Implications of 3D Printed Bio-Based Homes, A Preliminary Honors College, University of Maine 758 (2022). <https://digitalcommons.library.umaine.edu/honors/758> [10] Trejo, E. M., Jimenez, X., Billah, K. M. M., Seppala, J., Wicker, R., & Espalin, D. “Compressive deformation analysis of large area pellet-fed material extrusion 3D printed parts in relation to in situ thermal imaging.” Additive Manufacturing 33 (2020): 101099. DOI: 10.1016/j.addma.2020.101099 [11] Compton, B. G., Post, B. K., Duty, C. E., Love, L., & Kunc, V. “Thermal analysis of additive manufacturing of large-scale thermoplastic polymer composites.” Additive Manufacturing 17 (2017): 77-86. DOI: 10.1016/j.addma.2017.07.006 [12] Sun, Q., Rizvi, G. M., Bellehumeur, C. T., & Gu, P. “Effect of processing conditions on the bonding quality of FDM polymer filaments.” Rapid Prototyping Journal 14(2) (2008): 72-80. DOI: 10.1108/13552540810862028 [13] Liu, L., Jo, E., Hoskins, D., Vaidya, U., Ozcan, S., Ju, F., & Kim, S. “Layer time optimization in large scale additive manufacturing via a reduced physics-based model.” Additive Manufacturing 72 (2023): 103597. DOI: 10.1016/j.addma.2023.103597 [14] Roschli, A., Gaul, K. T., Boulger, A. M., Post, B. K., Chesser, P. C., Love, L. J., Blue, F., & Borish, M. “Designing for Big Area Additive Manufacturing.” Additive Manufacturing 25 (2019: 275-285. DOI: 10.1016/j.addma.2018.11.006 [15] Duty, C., Ajinjeru C., Kishore, V., Compton, B., Hmeidat, N, Chen, X., Liu, P., Hassen, A. A., Lindahl, J., & Kunc, V. “What makes a material printable? A viscoelastic model for extrusion-based 3D printing of polymers.” Journal of Manufacturing Processes 35 (2018): 526-537. DOI: 10.1016/j.jmapro.2018.08.008 [16] SABIC. “Technical Data Sheet: LNP™ THERMOCOMP™ COMPOUND SF006.” (2024). <https://materialfinder.sabic-specialties.com> [17] ASTM Standard D618-21, 2021, “Standard Practice for Conditioning Plastics for Testing” ASTM International, West Conshohocken, PA, USA, 2021. DOI: 10.1520/D0618-21 [18] ASTM Standard D695-23, 2023, “Standard Test Method for Compressive Properties of Rigid Plastics” ASTM International, West Conshohocken, PA, USA, 2023. DOI: 10.1520/D069523 [19] Chatham, C. A., Zawaski, C. E., Bobbitt, D. C., Moore, R. B., Long, T. E., & Williams, C. B. “Semi-Crystalline Polymer Blends for Material Extrusion Additive Manufacturing Printability: A Case Study with Poly(ethylene terephthalate) and Polypropylene.” Macromolecular Materials and Engineering 304: 1800764. DOI: 10.1002/mame.201800764

Conference: CAMX 2025

Publication Date: 2025/09/08

SKU: 168

Pages: 15

Price: $30.00