Hygrothermal ageing behaviour of a glass/epoxy composite used in wind turbine blades

Hygrothermal ageing behaviour of a glass/epoxy composite used in wind turbine blades

Rocha, I.B.C.M. (TU Delft Applied Mechanics; Knowledge Centre WMC)
Raijmaekers, S (Knowledge Centre WMC)
Nijssen, RPL (Knowledge Centre WMC)
van der Meer, F.P. (TU Delft Applied Mechanics)
Sluys, Lambertus J. (TU Delft Applied Mechanics)

2017-08-15

In this work, a glass/epoxy material system applied in wind turbine blades was used to evaluate degradation processes induced by water ingression. Composite and neat epoxy specimens were conditioned in demineralised water at 50 °C for 4800 h and tested quasi-statically and in fatigue. Comparing results from mechanical tests in composite specimens, significant degradation was found, with up to 36% lower static shear strength and three orders of magnitude shorter fatigue life. For neat epoxy specimens, a lower degree of degradation was observed, with up to 17% lower tensile and bending moduli and strength. Specimens dried after having been immersed were also tested. For composite samples, recovery of shear stiffness and strength was incomplete. For neat resin, stiffness and bending strength were completely recovered but a decrease in the strain at failure was observed. It is hypothesised from differences in magnitude and reversibility of degradation between composite and neat resin that matrix degradation is accompanied by high differential swelling stresses and damage to the fibre/matrix interface in composites. The damage due to moisture ingression and the subsequent changes in failure behaviour are further investigated through thermal analysis (DSC, DMA) and optical microscopy.

Environmental degradation
Interface/Interphase
Mechanical testing
Polymer-matrix composites (PMCs)

http://resolver.tudelft.nl/uuid:d6733cfc-a58c-4d81-8a7f-0037b91823b3

https://doi.org/10.1016/j.compstruct.2017.04.028

2019-04-27

0263-8223

Composite Structures, 174, 110-122

Institutional Repository

journal article

© 2017 I.B.C.M. Rocha, S Raijmaekers, RPL Nijssen, F.P. van der Meer, Lambertus J. Sluys