A Modelling Approach for Predicting Residual Stresses and Distortions in Polymer Composites

High dimensional variability is inherent in the manufacture of fibre-reinforced composite components. In the aerospace industry, this stems largely from the elevated temperatures needed to process the composite materials, which give rise to residual, or frozen-in, stresses; these are exacerbated by chemical shrinkage of the resin during cure. These stresses can subsequently cause distortion and, in some instances, premature cracking of the moulding, which can only be relieved by expensive reworking and can, in severe cases, result in the structure being scrapped. The work has been aimed to develop reliable and accurate modelling tools to predict distortions in moulded components, ultimately allowing mould tools to be manufactured and curing regimes to be applied, which take these distortions into account. This will therefore result in lower cost and waste generation through ‘right-first-time’ manufacture.