Moisture absorption in graphite/epoxy laminates

Accelerated ageing versus realistic ageing in aerospace composite materials. IV. Hot/wet ageing effects in a low temperature cure epoxy composite

“…Previous research 7,9,17,18 has shown that the timing of these thermal spikes is also important. A too short time interval (hours) does not allow sufficient moisture equilibration, while intervals long enough to allow almost complete equilibration (many weeks) will have little impact on composite properties.…”

The effect of thermal spiking on moisture absorption, mechanical and viscoelastic properties of carbon fibre reinforced epoxy laminates

“…Certain aircraft components can be exposed to temperatures in excess of 100°C for only a few minutes [1]. Under such conditions of rapid heating followed by rapid cooling, studies have shown that the moisture absorption of epoxy/carbon laminates can increase significantly [2][3][4] relative to the control samples under constant hygrothermal conditions. The mechanism for this enhancement when the laminates are thermally spiked is not clear.…”

Environmental Degradation of Carbon Nanotube Hybrid Aerospace Composites

“…Many studies of the hot/wet ageing of aerospace composites and neat resin materials have been carried out (McKague et al 1975;Morgan and O'neal 1978;Springer 1982;Nicolais 1984, 1987;Collings and Stone 1985;Luoma and Rowland 1986;Clark et al 1990;Hancox 1998;Hough et al 1998;Ivanova et al 2001;Merdas et al 2002;Lin 2006). The academic literature has mainly relied on spectroscopic and dynamic mechanical studies to determine the chemistry and physics of moisture interaction with simple (noncommercial) formulations of neat resin.…”

“…The academic literature has mainly relied on spectroscopic and dynamic mechanical studies to determine the chemistry and physics of moisture interaction with simple (noncommercial) formulations of neat resin. The key experimental techniques used to identify changes due to environmental exposure involve spectroscopic, thermal, thermomechanical analysis mainly reported in the academic literature (McKague et al 1975;Morgan and O'neal 1978;Springer 1982;Collings and Stone 1985;Luoma and Rowland 1986;Apicella and Nicolais 1987;Ivanova et al 2001;Merdas et al 2002) and mechanical and fatigue tests mainly reported by the aerospace industry (Apicella and Nicolais 1984;Clark et al 1990;Hancox 1998;Hough et al 1998;Lin 2006). A brief summary of both areas was presented in the review by Hancox (1998) which included both literature references and standard test methods.…”