Title: High-Speed Radio-Frequency (RF) Welding of Carbon-Fiber–Polyetherketoneketone Laminates Using an Automated Platform

Authors: Sarmad Hassan, Agni Biswal, Vipin Kumar, Aniruddh Vashisth

DOI:

Abstract: We demonstrate rapid, controllable welding of carbon-fiber–polyetherketoneketone (CF/PEKK) laminates using radio-frequency (RF, 1–200 MHz) heating to deliver through-thickness heat precisely where joints form. RF fields couple directly with the carbon-fiber network and laminate permittivity to generate volumetric dielectric loss within the plies, so heat originates within the laminate and conducts outward to the surfaces, rather than the conventional outside-to-inside approach of hot bonders or IR lamps. An automated benchtop platform was developed to integrate a pneumatically actuated piston for pressure control, a stepper-driven translating stage for seam motion, and interchangeable RF applicators mounted on an adjustable end-effector to tune standoff, angle, and power. This configuration achieves heating rates up to 3,600 °C/min (60 °C/s), enabling sub-minute thermal cycles that minimize thermal exposure of surrounding structure. Methods include in-situ infrared thermography to map temperature fields and closedloop process windows, followed by mechanical validation on welded coupons (single-lap shear) and examining the weld morphology using microscopy. The results indicate a path to high-rate, automation-ready welding for aerospace and automotive structures with built-in avenues for quality assurance.

References: [1] H. (Hao) Wang et al., “Carbon Fiber Reinforced Thermoplastics: From Materials to Manufacturing and Applications,” Advanced Materials, vol. 37, no. 27, p. 2418709, Jul. 2025, doi: 10.1002/adma.202418709. [2] G. Pedoto, J.-C. Grandidier, M. Gigliotti, and A. Vinet, “Characterization and modelling of the PEKK thermomechanical and creep behavior above the glass transition temperature,” Mechanics of Materials, vol. 166, p. 104189, Mar. 2022, doi: 10.1016/j.mechmat.2021.104189. [3] C. Yildirim, H. Ulus, H. S. Sas, and M. Yildiz, “Evaluating the influence of service conditions on the out-of-plane and in-plane loading performance and damage behavior of unidirectional CF/PEKK composites for aerospace applications,” Composites Part B: Engineering, vol. 304, p. 112637, Sep. 2025, doi: 10.1016/j.compositesb.2025.112637. [4] J. Weber and J. Schlimbach, “Co-consolidation of CF/PEEK tape-preforms and CF/PEEK organo sheets to manufacture reinforcements in stamp-forming process,” Advanced Manufacturing: Polymer & Composites Science, vol. 5, no. 4, pp. 172–183, Oct. 2019, doi: 10.1080/20550340.2019.1673961. [5] J. Swamy, S. Wijskamp, T. Asijee, and E. Krämer, “ADVANCES IN OUT-OFAUTOCLAVE CONSOLIDATION OF THERMOPLASTIC COMPOSITES,” in SAMPE 2023, NA SAMPE, 2023. doi: 10.33599/nasampe/s.23.0320. [6] C. B. G. Brito, J. Teuwen, C. A. Dransfeld, and I. F. Villegas, “Ultrasonic welding of thermoplastic composites: A comparison between polyetheretherketone and low-melt polyaryletherketone as resin in the adherends and energy directors,” Composites Part B: Engineering, vol. 296, p. 112264, May 2025, doi: 10.1016/j.compositesb.2025.112264. [7] S. K. Bhudolia, G. Gohel, K. F. Leong, and A. Islam, “Advances in Ultrasonic Welding of Thermoplastic Composites: A Review,” Materials, vol. 13, no. 6, p. 1284, Mar. 2020, doi: 10.3390/ma13061284. [8] [9] H. Perrin, G. Mertz, N.-L. Senoussaoui, L. Borghini, S. Klein, and R. Vaudemont, “Surface functionalization of thermoset composite for infrared hybrid welding,” Functional Composite Mater, vol. 2, no. 1, p. 10, Dec. 2021, doi: 10.1186/s42252-021-00021-5. A. K. Biswal, A. Nandi, H. Wang, and A. Vashisth, “Ultrasonic welding of fiber reinforced vitrimer composites,” Composites Science and Technology, vol. 242, p. 110202, Sep. 2023, doi: 10.1016/j.compscitech.2023.110202. [10] T. J. Ahmed, D. Stavrov, H. E. N. Bersee, and A. Beukers, “Induction welding of thermoplastic composites—an overview,” Composites Part A: Applied Science and Manufacturing, vol. 37, no. 10, pp. 1638–1651, Oct. 2006, doi: 10.1016/j.compositesa.2005.10.009. [11] R. G. Martin, C. Johansson, J. R. Tavares, and M. Dubé, “CF/PEEK skins assembly by induction welding for thermoplastic composite sandwich panels,” Composites Part B: Engineering, vol. 284, p. 111676, Sep. 2024, doi: 10.1016/j.compositesb.2024.111676. [12] A. Vashisth, S. T. Upama, M. Anas, J.-H. Oh, N. Patil, and M. J. Green, “Radio frequency heating and material processing using carbon susceptors,” Nanoscale Adv., vol. 3, no. 18, pp. 5255–5264, 2021, doi: 10.1039/D1NA00217A. [13] M. Anas et al., “Universal patterns of radio-frequency heating in nanomaterial-loaded structures,” Applied Materials Today, vol. 23, p. 101044, Jun. 2021, doi: 10.1016/j.apmt.2021.101044. [14] A. Vashisth, R. E. Healey, M. J. Pospisil, J. H. Oh, and M. J. Green, “Continuous processing of pre-pregs using radio frequency heating,” Composites Science and Technology, vol. 195, p. 108211, Jul. 2020, doi: 10.1016/j.compscitech.2020.108211. [15] I. Enriquez et al., “Closed-Loop Composite Welding and Bonding System Using RadioFrequency Heating and Pressure,” J. Compos. Sci., vol. 7, no. 3, p. 116, Mar. 2023, doi: 10.3390/jcs7030116. [16] A. K. Biswal, S. Gupta, X. Zhou, T. K. Lewis, J. Tang, and A. Vashisth, “Radio frequency (RF) enabled forming of vitrimers for moldless manufacturing,” Carbon, vol. 238, p. 120304, May 2025, doi: 10.1016/j.carbon.2025.120304.

Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 56

Pages: 10

Price: $20.00