Experimental setup and method for the characterization of ply-ply adhesion for fiber-reinforced thermoplastics in melt

Experimental setup and method for the characterization of ply-ply adhesion for fiber-reinforced thermoplastics in melt


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Abstract. Process simulation software for hot press forming is a vital tool for the development of complex continuous fiber-reinforced thermoplastic parts for structural applications. The simulation tools need to be accurate to truly facilitate the design stage, which in turn requires accurate material characterizations and constitutive models. The material forming behavior is composed of different deformation mechanisms, one of which is the separation of adjacent plies or delamination. Currently, the resistance against delamination or ply-ply adhesion is modeled as a constant tensile stress that needs to be overcome, the value of which is based on an educated guess. To date, no standard exists to characterize this material property for thermoplastic matrix composites (TPC) in melt. Hence, we discuss and evaluate several methods to measure ply-ply adhesion of TPCs. The most promising approach, a so-called probe test, was further pursued and a setup was designed and manufactured for the use in a rheometer. Subsequently, we measured the required normal force to separate two C/LM-PAEK tapes in melt. Repeated tests on the same specimen resulted in an increasing adhesive peak force, which we relate to a change in the amount and distribution of the matrix material at the ply’s surface. The peak force increased also with increasing compression time and pressure. We found a reasonable correlation of the average measured peak force with the values currently assumed in simulation software.

Hot Press Forming, Thermoplastic Matrix Composites (TPC), Ply-Ply Adhesion

Published online 4/19/2023, 10 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: PIERIK Rens, ROUWMAAT Thijs, GROUVE Wouter, WIJSKAMP Sebastiaan, AKKERMAN Remko, Experimental setup and method for the characterization of ply-ply adhesion for fiber-reinforced thermoplastics in melt, Materials Research Proceedings, Vol. 28, pp 267-276, 2023

DOI: https://doi.org/10.21741/9781644902479-29

The article was published as article 29 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

[1] T.K. Slange, Rapid Manufacturing of Tailored Thermoplastic Composites by Automated Lay-up and Stamp Forming, Ph.D. thesis, University of Twente, Enschede, The Netherlands, 2019.
[2] Y.M. Buser, G. Bieleman, W.J.B. Grouve, S. Wijskamp, R. Akkerman, Characterization of orthotropic electrical conductivity of unidirectional C/PAEK thermoplastic composites, in: 20th European Conference on Composite Materials, Lausanne, Switzerland: ECCM, 2022.
[3] S.P. Haanappel, R.H.W. Ten Thije, U. Sachs, B. Rietman, R. Akkerman, Formability analyses of uni-directional and textile reinforced thermoplastics, Compos. Part A 56 (2014) 80-92. https://doi.org/10.1016/j.compositesa.2013.09.009
[4] AniForm, Virtual Forming, Information on http://www.aniform.com. (accessed 31 January 2023).
[5] S.P. Haanappel, Forming of UD Fibre Reinforced Thermoplastics, PhD Thesis, University of Twente, Enschede, The Netherlands, 2013.
[6] D. Dörr, M. Faisst, T. Joppich, C. Poppe, F. Henning, L. Kärger, Modelling approach for anisotropic inter-ply slippage in finite element forming simulation of thermoplastic UD-tapes, in: 21th International Conference on Material Forming, Palermo, Italy: ESAFORM, 2018, 020005.
[7] E.R. Pierik, W.J.B. Grouve, S. Wijskamp, R. Akkerman, On the origin of start-up effects in ply-ply friction for UD fiber-reinforced thermoplastics in melt, in: 24th International Conference on Material Forming, Liège, Belgium: ESAFORM, 2021, 3695.
[8] E.R. Pierik, W.J.B. Grouve, S. Wijskamp, R. Akkerman, Prediction of the peak and steady-state ply-ply friction response for UD C/PAEK tapes, Compos. Part A 163 (2022) 107185. https://doi.org/10.1016/j.compositesa.2022.107185
[9] P.D. Mulye, J. Hemmer, L. Morançay, C. Binetruy, A. Leygue, S. Comas-Cardona, P. Pichon, D. Guillon, Numerical modeling of interply adhesion in composite forming of viscous discontinuous thermoplastic prepregs, Compos. Part B 191 (2020) 107953. https://doi.org/10.1016/j.compositesb.2020.107953
[10] D. Budelmann, H. Detampel, C. Schmidt, D. Meiners, Interaction of process parameters and material properties with regard to prepreg tack in automated lay-up and draping processes, Compos. Part A 117 (2019) 308-316. https://doi.org/10.1016/j.compositesa.2018.12.001
[11] K.J. Ahn, J.C. Seferis, T. Pelton, M. Wilhelm, Analysis and characterization of prepreg tack, Polym. Compos. 13 (1992) 197-206. https://doi.org/10.1002/pc.750130308
[12] O. Dubois, J.-B. Le Cam, A. Béakou, Experimental analysis of prepreg tack, Exp. Mech. 50 (2010) 599-606. https://doi.org/10.1007/s11340-009-9236-7
[13] A. Endruweit, G.Y.H. Choong, S. Ghose, B.A. Johnson, D.R. Younkin, N.A. Warrior, D.S.A. De Focatiis, Characterisation of tack for uni-directional prepreg tape employing a continuous application-and-peel test method, Compos. Part A 114 (2018) 295-306. https://doi.org/10.1016/j.compositesa.2018.08.027
[14] R.P. Wool, B.-L. Yuan, O.J. McGarel, Welding of polymer interfaces, Polym. Eng. Sci. 29 (1989) 1340-1367.
[15] J. Avenet, A. Levy, J.-L. Bailleul, S. Le Corre, J. Delmas, Adhesion of high performance thermoplastic composites: development of a bench and procedure for kinetics identification, Compos. Part A 138 (2020) 106054. https://doi.org/10.1016/j.compositesa.2020.106054
[16] O. Çelik, D. Peeters, C. Dransfeld, J. Teuwen, Intimate contact development during laser assisted fiber placement: microstructure and effect of process parameters, Compos. Part A 134 (2020) 105888. https://doi.org/10.1016/j.compositesa.2020.105888
[17] P.G. de Gennes, Reptation of a polymer chain in the presence of fixed obstacles, J. Chem. Phys. 55 (1971) 572-579. 10.1063/1.1675789
[18] F.N. Cogswell, Thermoplastic Aromatic Polymer Composites, Butterworth-Heinemann, Oxford, United Kingdom, 1992. ISBN: 978-0-7506-1086-5
[19] F. Yang, R. Pitchumani, Healing of thermoplastic polymers at an interface under nonisothermal conditions, Macromolecules 35 (2002) 3213-24. https://doi.org/10.1021/ma010858o
[20] A. Levy, D. Heider, J. Tierney, J.W. Gillespie, Inter-layer thermal contact resistance evolution with the degree of intimate contact in the processing of thermoplastic composite laminates, J. Compos. Mater. 48 (2013) 491-503. https://doi.org/10.1177/0021998313476318
[21] D. Budelmann, C. Schmidt, D. Meiners, Prepreg tack: a review of mechanisms, measurement, and manufacturing implication, Polym. Compos. 41 (2020) 3440-3458. https://doi.org/10.1002/pc.25642
[22] R.J. Crossley, P.J. Schubel, N.A. Warrior, The experimental characterization of prepreg tack, in: 17th Inter. Conference on Composite Materials, Edinburgh, United Kingdom: ICCM, 2009.
[23] D.R. Moore, J.G. Williams, A protocol for determination of the adhesive fracture toughness of flexible laminates by peel testing: fixed arm and T-peel methods, ESIS protocol, 2010.