Moisture Absorption of Graphite-Epoxy Composites Immersed in Liquids and in Humid Air

Loos, Alfred C.; Springer, George Ś.

doi:10.1177/002199837901300205

Cited by 206 publications

(117 citation statements)

References 9 publications

Supporting

Mentioning

108

Contrasting

Unclassified

Order By: Relevance

“…When the equilibrium state is reached, the maximum moisture content of the neat resin may be estimated from the maximum moisture content of the composite. By assuming that the fibers do not absorb any moisture, ÁC I and ÁC m are related by the expression given by Loos and Springer [13]:…”

Section: Prediction Of the Homogenized Hygroelastic Properties Of A Plymentioning

confidence: 99%

See 1 more Smart Citation

A Hygroelastic Self-consistent Model for Fiber-reinforced Composites

Jacquemin

Fréour

Guillén

2005

Journal of Reinforced Plastics and Composites

View full text Add to dashboard Cite

Stress analyses are performed in unidirectional fiber-reinforced composites, exposed to ambient fluid, by extending a classical self-consistent model to hygroelastic solicitations. Constitutive laws are given for the macroscopic elastic properties and Coefficients of Moisture Expansion (CME) by considering a jump in moisture content between the fiber and the matrix. Inverse forms for the unknown CME of the constituent matrix are proposed. The macroscopic (ply) and local (fiber and matrix) internal stress states are evaluated for various moisture content ratios between the matrix and the ply. The macroscopic stresses are calculated by using continuum mechanics formalisms and the local stresses are deduced from the scale transition model.

show abstract

Section: Prediction Of the Homogenized Hygroelastic Properties Of A Plymentioning

confidence: 99%

“…The permanent concentration (noticed Table 5. Hygroscopic properties for T300/5208 composite [13]. 'perm' in the caption) holds with a constant value because of the symmetric hygroscopic loading.…”

Section: Macroscopic Stress Statementioning

confidence: 99%

A Hygroelastic Self-consistent Model for Fiber-reinforced Composites

Jacquemin

Fréour

Guillén

2005

Journal of Reinforced Plastics and Composites

View full text Add to dashboard Cite

show abstract

“…These structures are typically constructed of polymer fiberreinforced composites due to the associated low weight, rigidity, impact protection and ability to maintain transparency to incoming radar waves. However, a significant concern throughout the service life of the polymer composite radome is its tendency to absorb moisture [2]. Assessment of the deleterious effects of moisture ingress on the mechanical properties of fiber-reinforced composites has garnered much focus throughout several decades of research [3][4][5][6][7].…”

Section: Introductionmentioning

confidence: 99%

Reversible dielectric property degradation in moisture-contaminated fiber-reinforced laminates

Rodríguez

Garcia

Fittipaldi

et al. 2016

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract. The potential for recovery of dielectric properties of three water-contaminated fiber-reinforced laminates is investigated using a split-post dielectric resonant technique at X-band (10 GHz). The three material systems investigated are bismaleimide (BMI) reinforced with an eight-harness satin weave quartz fabric, an epoxy resin reinforced with an eightharness satin weave glass fabric (style 7781), and the same epoxy reinforced with a four-harness woven glass fabric (style 4180). A direct correlation between moisture content, dielectric constant, and loss tangent was observed during moisture absorption by immersion in distilled water at 25°C for five equivalent samples of each material system. This trend is observed through at least 0.72% water content by weight for all three systems. The absorption of water into the BMI, 7781 epoxy, and 4180 epoxy laminates resulted in a 4.66%, 3.35%, and 4.01% increase in dielectric constant for a 0.679%, 0.608%, and 0.719% increase in water content by weight, respectively. Likewise, a significant increase was noticed in loss tangent for each material. The same water content is responsible for a 228%, 71.4%, and 64.1% increase in loss tangent, respectively. Subsequent to full desorption through drying at elevated temperature, the dielectric constant and loss tangent of each laminate exhibited minimal change from the dry, pre-absorption state. The dielectric constant and loss tangent change after the absorption and desorption cycle, relative to the initial state, was 0.144 % and 2.63% in the BMI, 0.084% and 1.71% in the style 7781 epoxy, and 0.003% and 4.51% in the style 4180 epoxy at near-zero moisture content. The similarity of dielectric constant and loss tangent in samples prior to absorption and after desorption suggests that any chemical or morphological changes induced by the presence of water have not caused irreversible changes in the dielectric properties of the laminates.

show abstract

“…By assuming that the fibers do not absorb any moisture, ÁC I and ÁC m are related by the expression given by Loos and Springer [17]:…”

Section: Comparison Between Analytical and Numerical Sc Models Introdmentioning

confidence: 99%

On an Analytical Self-consistent Model for Internal Stress Prediction in Fiber-reinforced Composites Submitted to Hygroelastic Load

Fréour

Jacquemin

Guillén

2005

Journal of Reinforced Plastics and Composites

View full text Add to dashboard Cite

. On an analytical Self-Consistent model for internal stress prediction in fiber-reinforced composites submitted to hygroelastic load. The aim of this work is to demonstrate a fully explicit analytical micromechanical self consistent approach dedicated to mechanical states prediction in both the fiber and the matrix of composite structures submitted to a transient hygroelastic load. The analytical forms obtained are applied to the case of carbon epoxy composites. Rigorous continuum mechanics formalisms are used for the determination of the required time and space dependent macroscopic stresses. The reliability of the new approach is checked through a comparison between the local stress states calculated in both the resin and the fiber according to the new closed form solutions and the equivalent numerical model.

show abstract

Moisture Absorption of Graphite-Epoxy Composites Immersed in Liquids and in Humid Air

Cited by 206 publications

References 9 publications

A Hygroelastic Self-consistent Model for Fiber-reinforced Composites

A Hygroelastic Self-consistent Model for Fiber-reinforced Composites

Reversible dielectric property degradation in moisture-contaminated fiber-reinforced laminates

On an Analytical Self-consistent Model for Internal Stress Prediction in Fiber-reinforced Composites Submitted to Hygroelastic Load

Contact Info

Product

Resources

About