An experimental–numerical investigation of hydrothermal response in adhesively bonded composite structures

Published on Jun 1, 2015in Composites Part A-applied Science and Manufacturing6.444
· DOI :10.1016/J.COMPOSITESA.2015.03.005
Roohollah Sarfaraz8
Estimated H-index: 8
(EPFL: École Polytechnique Fédérale de Lausanne),
Luis P. Canal11
Estimated H-index: 11
(EPFL: École Polytechnique Fédérale de Lausanne)
+ 3 AuthorsHans G. Limberger24
Estimated H-index: 24
(EPFL: École Polytechnique Fédérale de Lausanne)
Water absorption and thermal response of adhesive composite joints were investigated by measurements and numerical simulations. Water diffusivity, saturation, swelling, and thermal expansion of the constituent materials and the joint were obtained from gravimetric experiments and strain measurements using embedded fiber Bragg grating (FBG) sensors. The mechanical response of these materials at different temperatures and water content was characterized by dynamic mechanical analysis. Thermal loading and water absorption in joint specimens were detected by monitoring the FBG wavelength shift caused by thermal expansion or water swelling. The measured parameters were used in finite element models to simulate the response of the embedded sensor. The good correlation of experimental data and simulations confirmed that the change in FBG wavelength could be accurately related to the thermal load or water absorption process. The suitability of the embedded FBG sensors for monitoring of water uptake in adhesive composite joints was demonstrated. (C) 2015 Elsevier Ltd. All rights reserved.
📖 Papers frequently viewed together
1 Citations
2 Authors (H. K. Liu, R. L. Kurtz)
26 Citations
#1James E. ShelbyH-Index: 3
Introduction Principles of Glass Formation Glass Melting Immiscibility/Phase Separation Structure of Glasses Viscosity of Glassforming Melts Density and Thermal Expansion Transport Properties Mechanical Properties Optical Properties Glass Technology Bibliography Subject Index.
1,076 Citations
#1Gustavo Quino (KAUST: King Abdullah University of Science and Technology)H-Index: 3
#2Jalal El Yagoubi (KAUST: King Abdullah University of Science and Technology)H-Index: 4
Last. Gilles Lubineau (KAUST: King Abdullah University of Science and Technology)H-Index: 39
view all 3 authors...
Abstract Characterizing the change in toughness of polymers subjected to wet aging is challenging because of the heterogeneity of the testing samples. Indeed, as wet aging is guided by a diffusion/reaction process, compact tension samples (defined by the ASTM D5045 standard), which are relevant for toughness characterization but are somewhat thick, display a non-uniform moisture content over the bulk material. We define here a rigorous procedure to extract meaningful data from such tests. Our re...
23 CitationsSource
#1Shin-ichi Takeda (JAXA: Japan Aerospace Exploration Agency)H-Index: 15
#2Takuhei Tsukada (Hokkaido University)H-Index: 4
Last. Yutaka Iwahori (JAXA: Japan Aerospace Exploration Agency)H-Index: 16
view all 4 authors...
Abstract Practical monitoring technologies are needed for evaluating water absorption/desorption in actual CFRP structures. In this study, the monitoring of water absorption in laminated CFRPs was demonstrated by a simple evaluation using fiber Bragg grating (FBG) sensors. The swelling strain and coefficient of moisture expansion (CME) of unidirectional (UD) laminates were estimated from the axial strain of FBGs. The measured swelling strains of cross-ply laminates agreed with that obtained from...
15 CitationsSource
#1Luis P. Canal (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 11
#2Roohollah Sarfaraz (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 8
Last. Hans G. Limberger (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 24
view all 6 authors...
The adhesive bonding of composite materials can be applied to assemble light-weight structures for aeronautical applications. However, the application of adhesive bonds in primary load-bearing structures is limited by the lack of adequate techniques to monitor the quality of the joint during service. This work evaluates the feasibility of using Fiber Bragg Grating (FBG) arrays to monitor the distribution of strains developed along the bonded region in single lap shear specimens. Three different ...
39 CitationsSource
#1Luis P. Canal (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 11
#2Véronique Michaud (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 49
Water diffusion into composite adhesive joints was experimentally studied by means of gravimetric measurements in bond specimens. The main parameters controlling the diffusion in the bond components were obtained from water uptake experiments carried out in bulk specimens of fiber-reinforced composite and epoxy adhesive. The diffusion of water in bonds is a complex mechanism due to the heterogeneous microstructure of the composite and its interface with the adhesive. This process was simulated t...
10 CitationsSource
#1M. Lai (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 5
#2John Botsis (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 37
Last. Joël Cugnoni (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 26
view all 3 authors...
Abstract The hydrothermal ageing of glass/epoxy interface is investigated using an experimental–numerical approach on cylindrical epoxy specimens with centrally located optical fibers. A 24 mm long Bragg grating sensor is inscribed on the optical fiber and used to monitor strains along the fiber, due to processing and subsequent ageing in water at 50 °C. The distributed strains are used to: (a) evaluate the residual strain field developed during processing, employing a parametric finite element ...
14 CitationsSource
#1Jalal El YagoubiH-Index: 4
#2Gilles Lubineau (KAUST: King Abdullah University of Science and Technology)H-Index: 39
Last. Abe AskariH-Index: 9
view all 5 authors...
In this paper, we study the hygrothermal aging of an anhydride-cured epoxy under temperature and hygrometry conditions simulating those experienced by an aircraft in wet tropical or subtropical regions. Gravimetric and dimensional measurements were performed and they indicate that there are three stages in this aging process: the rst one, corresponding to the early cycles can be called the \induction stage". The second stage of about 1000 cycles duration, could be named the the \swelling stage",...
24 CitationsSource
#1Jalal El Yagoubi (KAUST: King Abdullah University of Science and Technology)H-Index: 4
#2Gilles Lubineau (KAUST: King Abdullah University of Science and Technology)H-Index: 39
Last. Jacques Verdu (Arts et Métiers ParisTech)H-Index: 55
view all 4 authors...
Abstract Thermoset materials frequently display non-classical moisture sorption behaviors. In this paper, we investigated this issue from an experimental point of view as well as in terms of modeling the water transport. We used the gravimetric technique to monitor water uptake by epoxy samples, with several thicknesses exposed to different levels of humidity during absorption and desorption tests. Our results revealed that the polymer displays a two-stage behavior with a residual amount of wate...
55 CitationsSource
#1John BotsisH-Index: 37
Fiber optic sensors have been extensively used for measuring strain, temperature, pressure, humidity, and other quantities in various experimental configurations. Compared to other traditional sensors, they have a number of advantages. They are generally more compact, lightweight, and less invasive because of their small size (125 µm is the standard diameter of the fiber). In addition, they are immune to electromagnetic interference, have excellent resistance to corrosion and high temperatures, ...
11 CitationsSource
#1M. Lai (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 5
#2John Botsis (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 37
Last. Dragan Coric (EPFL: École Polytechnique Fédérale de Lausanne)H-Index: 5
view all 4 authors...
It is well known that moisture absorption impairs the mechanical and physical properties of polymers. Conventionally, the material's hygric strains are described as the product of a constant coefficient of moisture expansion (CME) and moisture concentration. This hypothesis, however, has not been thoroughly examined experimentally. In this paper, the hygro-mechanical response of a DGBA based epoxy is reported as a function of moisture uptake. Cylindrical specimens are made of epoxy with an axial...
28 CitationsSource
Cited By3
#1Neele Grundmann (Fraunhofer Society)H-Index: 1
#2Hauke Brüning (Fraunhofer Society)H-Index: 5
Last. Bernd Mayer (University of Bremen)H-Index: 5
view all 5 authors...
The increasing utilization of carbon fiber reinforced plastic (CFRP) in the aeronautical industry calls for a structural health monitoring (SHM) system for adhesively bonded CFRP joints. Optical glass fiber with inscribed fiber Bragg gratings (FBGs) is a promising technology for a SHM system. This paper investigates the intrusive effect of embedding optical glass fibers carrying FBGs on adhesive bond strength and adhesive layer thickness and quality. Embedding the optical glass fibers directly i...
5 CitationsSource
#1RL Rito (University of Surrey)H-Index: 1
#2A.D. Crocombe (University of Surrey)H-Index: 46
Last. Stephen L. Ogin (University of Surrey)H-Index: 24
view all 3 authors...
This paper presents an experimental and numerical study on the structural health monitoring of composite patch repairs using chirped fibre Bragg grating (CFBG) sensors. The repair consisted of bonding a pre-cured patch of the same, but thinner, material to a parent GFRP panel containing a machined hole, with the sensors embedded in the bond-line. The repaired coupons were subjected to four-point flexural loading in fatigue. Bond-line delamination cracks (disbonds) initiated at both ends of the p...
15 CitationsSource
#1Romain Ecault (Airbus Group)H-Index: 8
#2Fabienne Touchard (University of Poitiers)H-Index: 16
Last. Nicolas Dominguez (Airbus Group)H-Index: 4
view all 5 authors...
Abstract In this work, laser shock experiments on composite material are modeled. Focus is made on the development of a reliable numerical model to be used for the laser shock wave adhesion test of bonded composites. Technique principle is explained as well as the laser shock experiment procedure. Then, the numerical investigations are presented. A calibration method is given to set the model input parameters, and the modeling choices are detailed. Dynamic material parameters are identified than...
14 CitationsSource