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Experimental and predictive analysis of the molding behavior of a PA6 glass mat thermoplastic (GMT)

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Abstract

The material targeted in this study is TEPEX® flowcore, a long glass fiber mat reinforced polyamide (PA6/GF) manufactured by Lanxess. The material is classified experimentally on coupon level, and the kinetic behavior is analyzed through standard and flash DSC analyses. Subsequently, results from experimental molding trials are investigated concerning material forming and material flow. Finally, molding behavior is analyzed on a predictive basis using a thermokinetic and a rheological model. It is found that molding of the PA6 GMT comprises the sequential stages of material forming and material forming, in combination with the respective defects wrinkling and incomplete mold filling. Flowability is found to be rather limited, given the usually adopted thin stacking heights (\(\lesssim 8 \, \text {mm}\)), a minimum achievable part thickness (\(> 3 \, \text {mm}\)), and a maximum specific pressure (\(< 500 \, \text {bar}\)). Finally, it is shown that the experimentally observed no wall slip results from an instant solidification of the sheet surface due to the significant difference in mold wall and charge temperature.

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References

  1. Schemme M (2008) LFT - development status and perspectives. Plastics, Additives and Compounding 10(2):38–43

    Article  Google Scholar 

  2. Kutz M (2017) Applied plastics engineering handbook: processing, materials, and applications. Plastics design library PDL handbook series. Elsevier/William Andrew, Amsterdam and Boston and Heidelberg, second edition edition

  3. Bruderick M, Denton D, Shinedling M, Kiesel M (2002) Applications of carbon/fiber SMC for the 2003 Dodge Viper. Second SPE Automotive Composites Conference (vol 10)

  4. Gardinger G (2016) Is the BMW 7 series the future of autocomposites?

  5. Burn D (2016) Long discontinuous carbon fibre/polypropylene composites for high volume automotive applications. Doctoral thesis, University of Nottingham, Nottingham

  6. Davis BA, Gramann PJ, Osswald PJ, Rios AC (2003) Compression molding. Hanser, Munich

    Google Scholar 

  7. Grove DA (2005) Composite processes. In: Harper CA (ed) Handbook of Plastic Processes. John Wiley & Sons Inc, Hoboken, NJ, USA, pp 475–527

    Google Scholar 

  8. Osswald TA (1998) Polymer processing fundamentals. SPE books, Hanser and Hanser/Gardner, Munich and Cincinnati

    Google Scholar 

  9. Wakeman MD, Rudd CD (2000) Compression molding of thermoplastic composites. In Comprehensive Composite Materials, pp 915–963. Elsevier

  10. Jespersen ST, Baudry F, Schmäh D, Wakeman MD, Michaud V, Blanchard P, Norris RE, Månson J-AE (2009) Rapid processing of net-shape thermoplastic planar-random composite preforms. Appl Compos Mater 16(1):55–71

    Article  Google Scholar 

  11. Haque E, Bristow P, Giles H (2001) Processing of glass fiber mat reinforced thermoplastic composites. Dallas, TX: Society of Plastics Engineers ANTEC 2001:2079–2083

    Google Scholar 

  12. Bernet N, Michaud V, Bourban P-E, Månson J-AE (2001) Commingled yarn composites for rapid processing of complex shapes. Compos A: Appl Sci Manuf 32(11):1613–1626

    Article  Google Scholar 

  13. Sattar S, Beltran Laredo B, Pedrazzoli D, Zhang M, Kravchenko SG, Kravchenko OG (2022) Mechanical behavior of long discontinuous glass fiber nylon composite produced by in-situ polymerization. Compos A: Appl Sci Manuf 154:106779

    Article  Google Scholar 

  14. Heer N, Ivanov S, Meirson G, Ugresic V, Henning F, Hrymak A, Zhang M (2020) Versatility of Long Fiber AP Nylon CR-6 Organosheet to overcome intrinsic short comings of Long Fiber Thermoplastics. SPE-ACCE 2020 conference proceedings

  15. Dörr D, Singh-Heer N, Gergely RCR, Schreyer L, Henning F, Straatman AG, Hrymak A (2022) Rheological characterization and macroscopic modeling and simulation of the molding process of a PA6 glass mat thermoplastic (GMT). Journal of Composites: Part A (revision submitted)

  16. Dörr D, Singh-Heer N, Gergely RCR, Okonski D, Henning F, Straatman AG, Hrymak A (2022) Towards a virtual process chain for glass mat thermoplastics as a basis for digital product development. SPE ACCE Proceedings

  17. Dörr D, Gergely R, Ivanov S, Kärger L, Henning F, Hrymak A (2020) On the applicability of thermoforming characterization and simulation approaches to glass mat thermoplastic composites. Procedia Manufacturing 47:118–125

    Article  Google Scholar 

  18. Dörr D, Ivanov S, Gergely R, Meyer N, Henning F, Straatman AG, Hrymak A (2021) A sequential approach for simulation of thermoforming and squeeze flow of glass mat thermoplastics. ESAFORM 2021

  19. Xu C, Ivanov S, Gergely R, Dörr D, Hrymak A, Henning F (2021) Characterization of heat transfer parameters in the compression molding of glass mat thermoplastics. SPE ACCE Proceedings

  20. Knezevic D, Tutunea-Fatan OR, Gergely R, Okonski DA, Ivanov S, Dörr D (2022) Thermographic analysis of a long fiber-reinforced thermoplastic compression molding process. The International Journal of Advanced Manufacturing Technology 119(9–10):6119–6133

    Article  Google Scholar 

  21. Lanxess (2017) Material data sheet Tepex flowcore 102-RGR2400/47%

  22. AZO Materials (2022) E-glass fibre, January 27, 2022

  23. Krause M, Hausherr JM, Burgeth B, Herrmann C, Krenkel W (2010) Determination of the fibre orientation in composites using the structure tensor and local X-ray transform. J Mater Sci 45(4):888–896

    Article  Google Scholar 

  24. Pinter P, Dietrich S, Bertram B, Kehrer L, Elsner P, Weidenmann KA (2018) Comparison and error estimation of 3D fibre orientation analysis of computed tomography image data for fibre reinforced composites. NDT & E International 95:26–35

    Article  Google Scholar 

  25. Advani SG, Tucker CL (1987) The use of tensors to describe and predict fiber orientation in short fiber composites. J Rheol 31(8):751–784

    Article  Google Scholar 

  26. Kanatani K-I (1984) Distribution of directional data and fabric tensors. Int J Eng Sci 22(2):149–164

    Article  MathSciNet  MATH  Google Scholar 

  27. Dahl J, Blashard P, Latimer T, Sudria J, Henshaw J (2011) A method for characterizing fiber length distribution in random fiber composites. Society of Plastics Engineers - 11th-Annual Automotive Composites Conference and Exhibition

  28. National Institutes of Health (2022) Image J: image processing and analysis in Java

  29. Dörr D, Joppich T, Kugele D, Henning F, Kärger L (2019) A coupled thermomechanical approach for finite element forming simulation of continuously fiber-reinforced semi-crystalline thermoplastics. Compos A: Appl Sci Manuf 125:105508

    Article  Google Scholar 

  30. Haanappel SP, ten Thije RHW, Sachs U, Rietman B, Akkerman R (2014) Formability analyses of uni-directional and textile reinforced thermoplastics. Compos A: Appl Sci Manuf 56:80–92

    Article  Google Scholar 

  31. Kugele D (2020) Experimentelle und numerische untersuchung des abkühlverhaltens thermoplastischer gelegelaminate in der prozesskette

  32. Baehr HD, Stephan K (2006) Heat and mass transfer. Springer-Verlag Berlin Heidelberg, Berlin, Heidelberg, second revised edition edition

  33. Nakamura K, WatanabeT, Katayama K, Amano T (1972) Some aspects of nonisothermal crystallization of polymers. i. relationship between crystallization temperature, crystallinity, and cooling conditions. Journal of Applied Polymer Science 16(5):1077–1091

  34. Patel RM, Spruiell JE (1991) Crystallization kinetics during polymer processing–analysis of available approaches for process modeling. Polymer Engineering & Science 31(10):730–738

    Article  Google Scholar 

  35. Kugele D, Dörr D, Wittemann F, Hangs B, Rausch J, Kärger L, Henning F (2017) Modeling of the non-isothermal crystallization kinetics of polyamide 6 composites during thermoforming. AIP Conference Proceedings 1896:030005

    Article  Google Scholar 

  36. Hoffman JD, Weeks JJ (1962) Rate of spherulitic crystallization with chain folds in polychlorotrifluoroethylene. The Journal of Chemical Physics 37(8):1723–1741

    Article  Google Scholar 

  37. Ziabicki A (1976) Fundamentals of fibre formation: the science of fibre spinning and drawing. Wiley, London u.a

  38. Feng N, Wang X, Wu D (2013) Surface modification of recycled carbon fiber and its reinforcement effect on nylon 6 composites: mechanical properties, morphology and crystallization behaviors. Curr Appl Phys 13(9):2038–2050

    Article  Google Scholar 

  39. Kalaidov M, Meirson G, Heer N, Fan Y, Ivanov S, Ugresic V, Wood J, Hrymak A (2019) Viscosity measurement technique for long fiber thermoplastic material. SPE ACCE Proceedings

  40. Macosko CW (1994) Rheology: principles, measurements, and applications. Advances in interfacial engineering series, VCH, New York, NY

    Google Scholar 

  41. Mavridis H, Hrymak AN, Vlachopoulos J (1988) The effect of fountain flow on molecular orientation in injection molding. J Rheol 32(6):639–663

    Article  Google Scholar 

  42. Kamal MR, Goyal SK, Chu E (1988) Simulation of injection mold filling of viscoelastic polymer with fountain flow. AIChE Journal 34(1):94–106

    Article  Google Scholar 

  43. Mavridis H, Bruce GD, Vancso GJ, Weatherly GC, Vlachopoulos J (1992) Deformation patterns in the compression of polypropylene disks: experiments and simulation. J Rheol 36(1):27–43

    Article  Google Scholar 

  44. Osswald TA, Rudolph N (2015) Polymer rheology: fundamentals and applications. Hanser Publications Cincinnati

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Acknowledgements

The authors greatly appreciate the flash DSC work completed by Xiaoshi Zhang at Penn State Behrend. Moreover, the authors gratefully appreciate the carefully carried out fiber orientation analysis by Trevor Donald Sabiston (University of Waterloo), as well as the professional support on the shop floor by Rob Cosh, Steve Jones, and Keith Ruck (Fraunhofer Innovation Platform @ Western).

Funding

The authors acknowledge the funding support of General Motors of Canada, Natural Sciences and Engineering Research Council of Canada (Grant CRDPJ 518279-17), and the Ontario Centers of Excellence (Grant VIP2 28722).

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Authors and Affiliations

  1. Faculty of Engineering, University of Western Ontario (UWO), London, Ontario, Canada

    Dominik Dörr, Navraj Singh-Heer, Cheng Xu, Thomas Chang, Broderic Clement-Thorne, Frank Henning, Anthony G. Straatman & Andrew Hrymak

  2. Simutence GmbH, Karlsruhe, Germany

    Dominik Dörr

  3. GM Research and Development, General Motors, Warren, MI, USA

    Ryan C. R. Gergely & David Okonski

  4. Institute of Vehicle System Technology (FAST), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

    Frank Henning

  5. Fraunhofer Institute for Chemical Technology (ICT), Pfinztal, Germany

    Frank Henning

Authors
  1. Dominik Dörr
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  2. Navraj Singh-Heer
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  3. Cheng Xu
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  4. Thomas Chang
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  5. Broderic Clement-Thorne
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  6. Ryan C. R. Gergely
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  7. David Okonski
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  8. Frank Henning
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  9. Anthony G. Straatman
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  10. Andrew Hrymak
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Contributions

All authors contributed to the study’s conception and design. Material preparation and experimental data collection and analysis were performed by Dominik Dörr, Navraj Singh-Heer, Cheng Xu, Thomas Chang, and Broderic Clement-Thorne. The predictive analyses were developed and performed by Dominik Dörr. The first draft of the manuscript was written by Dominik Dörr. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

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Correspondence to Dominik Dörr.

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Dörr, D., Singh-Heer, N., Xu, C. et al. Experimental and predictive analysis of the molding behavior of a PA6 glass mat thermoplastic (GMT). Int J Adv Manuf Technol 129, 1159–1173 (2023). https://doi.org/10.1007/s00170-023-12017-5

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  • DOI: https://doi.org/10.1007/s00170-023-12017-5

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