Title: Investigation of Bead Overlap for Large-Scale Additive Manufacturing with Composites

Authors: Eric Luscher, Pasita Pibulchinda, R. Byron Pipes, Eduardo Barocio

DOI:

Abstract: The material properties of printed short carbon fiber reinforced polymers are highly dependent on the fiber orientation in the printed beads. The average fiber orientation state of a printed anisotropic material results in a directionally specific set of material properties. An understanding of this phenomenon during the extrusion deposition additive manufacturing (EDAM) process has been studied and analyzed in previous works. This study aims to investigate how the local fiber orientation states may vary in printed composite materials, even if the average fiber orientation state remains relatively unchanged. This study demonstrates that bead compaction results in a decrease in inter-bead voids when printing adjacent beads. Interbead voids lead to weak regions in the structure as well as to air paths that compromise vacuum integrity in printed tooling. The distance between the printed beads, defined as the bead overlap, is shown to slightly skew the fiber orientation within the bead, leading to changes in local fiber orientation. By understanding the local orientation, further knowledge of local changes in the material properties can be achieved. This is important when considering machining EDAM parts and using them as semi-structural components or for shape change predictions in tooling applications.

References: [1] “LSAM – Large Scale Additive Manufacturing.” Thermwood LSAM: Leading Large Format Additive Manufacturing (LFAM) Systems. Thermwood Corporation. 18 Dec. 2025 https://www.thermwood.com/lsam_home.htm. [2] Pibulchinda, P., Barocio, E., Favaloro, A. J. & Pipes, R. B. “Influence of printing conditions on the extrudate shape and fiber orientation in extrusion deposition additive manufacturing.” Composites Part B: Engineering 261 (2023). [3] Barocio, Eduardo. “Fusion Bonding of Fiber Reinforced Semi-Crystalline Polymers in Extrusion Deposition Additive Manufacturing.” Purdue University, West Lafayette, IN, 2018. [4] Pibulchinda, Pasita. “The Effects of Fiber Orientation State of Extrusion Deposition Additive Manufactured Fiber-Filled Thermoplastic Polymers.” Purdue University, West Lafayette, IN, 2020. [5] Pibulchinda, Pasita. “Lateral Fusion Bonding of Additive Manufactured Fiber-Reinforced Polymer Composites.” Purdue University Graduate School, West Lafayette, IN, 02 Aug. 2023. [6] Favaloro, Anthony. “Rheological Behavior and Manufacturing Simulation of Prepreg Platelet Molding Systems.” Purdue University, West Lafayette, IN, 2017. Doctoral dissertation. [7] Favaloro, A. J., Tseng, H. C. & Pipes, R. B. “A new anisotropic viscous constitutive model for composites molding simulation.” Composites Part A: Applied Science and Manufacturing 115 (2018). [8] Favaloro, A. J. & Sommer, D. E. “On the use of orientation tensors to represent prepreg platelet orientation state and variability.” Journal of Rheology 64(3) (2020). [9] Favaloro, A. J., Sommer, D. E., Denos, B. R. & Pipes, R. B. “Simulation of prepreg platelet compression molding: Method and orientation validation.” Journal of Rheology 62(6) (2018). [10] Favaloro, A. J., Sommer, D. E. & Pipes, R. B. “Manufacturing simulation of composites compression molding in Abaqus/Explicit.” Science in the Age of Experience (SIMULIA Global User Meeting). June 18–21, 2018. [11] Šeta, B., Sandberg, M., Brander, M., Mollah, M. T., Pokkalla, D. K., Kumar, V. & Spangenberg, J. “Numerical modeling of fiber orientation in multi-layer, isothermal material-extrusion big area additive manufacturing.” Additive Manufacturing 92 (2024). [12] “PESU: The High-Performance Polymer for Critical Applications.” Asep Industries. 19 Dec. 2025 https://www.asepindustries.com.my/post/pesu-high-performance-polymer. [13] Bangare, S. L., Dubal, A., Bangare, P. S. & Patil, S. “Reviewing Otsu’s method for image thresholding.” International Journal of Applied Engineering Research 10(9) (2015): 21777–21783. [14] Tucker III, Charles L. “Fundamentals of Fiber Orientation.” In Fundamentals of Fiber Orientation. Munich: Hanser Publishers, 2022. [15] Barocio, E., Kapre, V., Pibulchinda, P., Ramirez, M. A., Franc, A. & Susnjara, J. Material Characterization for Large Scale Additive Manufacturing (AM). Knoxville, TN: Institute for Advanced Composites Manufacturing Innovation, U.S. Department of Energy, 2022. [16] Doghri, I. & Tinel, L. “Micromechanical modeling and computation of elasto-plastic materials reinforced with distributed-orientation fibers.” International Journal of Plasticity 21(10) (2005). [17] Mori, T. & Tanaka, K. “Average stress in matrix and average elastic energy of materials with misfitting inclusions.” Acta Metallurgica 21(5) (1973).

Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 92

Pages: 15

Price: $30.00