The control of the residual lifetimes of carbon fibre-reinforced composite pressure vessels

International audienceThe understanding of the degradation of carbon fibre composites, with emphasis on the use of these composites in filament-wound pressure vessels, is explored. Earlier studies by many researchers have led to a general appreciation of the mechanisms involved; however, only recently have both computational power and experimental techniques become sufficiently developed to allow for the use of quantitative analyses. It is shown that damage is controlled by fibre failure, and that initially this occurs randomly within the structure. In monotonic loading, the development of clusters of fibre breaks causes rapid failure; however, under maintained loads the kinetics of damage evolution are markedly different, and final strength depends on the rate of loading. The results have direct implications for the use of composite pressure vessels, suggesting that their design and testing can be adapted to ensure long-term reliability. The ability to quantify damage accumulation in carbon fibre–composite pressure vessels allows for their intrinsic safety factors to be postulated