Life cycle strain monitoring in glass fibre reinforced polymer laminates using embedded fibre Bragg grating sensors from manufacturing to failure

Michael Wenani Nielsen, Jacob Wittrup Schmidt, Jacob Herold Høgh, Jacob Paamand Waldbjørn, Jesper Henri Hattel, Tom Løgstrup Andersen, Christen Malte Markussen

Research output: Contribution to journalJournal articleResearchpeer-review

703 Downloads (Pure)

Abstract

A holistic approach to strain monitoring in fibre-reinforced polymer composites is presented using embedded fibre Bragg grating sensors. Internal strains are monitored in unidirectional E-glass/epoxy laminate beams during vacuum infusion, curing, post-curing and subsequent loading in flexure until failure. The internal process-induced strain development is investigated through use of different cure schedules and tool/part interactions. The fibre Bragg grating sensors successfully monitor resin flow front progression during infusion, and strain development during curing, representative of the different cure temperatures and tool/part interfaces used. Substantial internal process-induced strains develop in the transverse fibre direction, which should be taken into consideration when designing fibre-reinforced polymer laminates. Flexure tests indicate no significant difference in the mechanical properties of the differently cured specimens, despite the large differences in measured residual strains. This indicates that conventional flexure testing may not reveal residual
strain or stress effects at small specimen scale levels. The internal stresses are seen to influence the accuracy of the fibre Bragg gratings within the loading regime. This study confirms the effectiveness of composite life cycle strain monitoring for developing consistent manufacturing processes.
Original languageEnglish
JournalJournal of Composite Materials
Volume48
Issue number3
Pages (from-to)365-381
ISSN0021-9983
DOIs
Publication statusPublished - 2013

Keywords

  • Strain monitoring
  • Fibre Bragg grating sensors
  • Curing
  • Process-induced strains
  • Life cycle
  • Composite

Fingerprint Dive into the research topics of 'Life cycle strain monitoring in glass fibre reinforced polymer laminates using embedded fibre Bragg grating sensors from manufacturing to failure'. Together they form a unique fingerprint.

Cite this