Numerical Investigation of Residual Stresses in Welded Thermoplastic CFRP Structures

Research output: Contribution to journalArticleResearchpeer review

Authors

  • Lukas Nagel
  • Alexander Herwig
  • Carsten Schmidt
  • Peter Horst

External Research Organisations

  • Technische Universität Braunschweig
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Details

Original languageEnglish
Article number45
Number of pages10
JournalJournal of Composites Science
Volume5
Issue number2
Publication statusPublished - 2 Feb 2021

Abstract

Using thermoplastics as the matrix in carbon fiber-reinforced polymers (CFRP) offers the possibility to make use of welded joints, which results in weight savings compared to conventional joining methods using mechanical fasteners. In this paper, the resulting temperature distribution in the material due to resistance welding is investigated by transient finite element (FE) simulations. To examine the effects on the component structure, a numerical modeling approach is created, which allows determining the residual stresses caused by the welding process. It is shown that the area of the structure, especially near the joining zone, is highly affected by the process, especially in terms of residual stresses. In particular, the stresses perpendicular to the fiber direction show failure relevant values up to a maximum of 221 MPa, which might lead to the formation of microcracks in the matrix. In turn, that is assumed to be critical in terms of the fatigue of welded composite structures. Thus, the suggested modeling approach provides residual stresses that can be used to determine their effects on the strength, structural stability, and fatigue of such composite structures. In a subsequent step, these findings could play an important role in the design process of thermoplastic composite structures.

Keywords

    Finite element modeling, Polymer– matrix composites (PMCs), Residual stress, Resistance welding, Thermomechanical behavior, Thermoplastics

ASJC Scopus subject areas

Cite this

Numerical Investigation of Residual Stresses in Welded Thermoplastic CFRP Structures. / Nagel, Lukas; Herwig, Alexander; Schmidt, Carsten et al.
In: Journal of Composites Science, Vol. 5, No. 2, 45, 02.02.2021.

Research output: Contribution to journalArticleResearchpeer review

Nagel, L, Herwig, A, Schmidt, C & Horst, P 2021, 'Numerical Investigation of Residual Stresses in Welded Thermoplastic CFRP Structures', Journal of Composites Science, vol. 5, no. 2, 45. https://doi.org/10.3390/jcs5020045, https://doi.org/10.15488/14622
Nagel, L., Herwig, A., Schmidt, C., & Horst, P. (2021). Numerical Investigation of Residual Stresses in Welded Thermoplastic CFRP Structures. Journal of Composites Science, 5(2), Article 45. https://doi.org/10.3390/jcs5020045, https://doi.org/10.15488/14622
Nagel L, Herwig A, Schmidt C, Horst P. Numerical Investigation of Residual Stresses in Welded Thermoplastic CFRP Structures. Journal of Composites Science. 2021 Feb 2;5(2):45. doi: 10.3390/jcs5020045, 10.15488/14622
Nagel, Lukas ; Herwig, Alexander ; Schmidt, Carsten et al. / Numerical Investigation of Residual Stresses in Welded Thermoplastic CFRP Structures. In: Journal of Composites Science. 2021 ; Vol. 5, No. 2.
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