Paper number 861
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CURING STRESSES IN THICK POLYMER COMPOSITE COMPONENTS PART II : MANAGEMENT OF RESIDUAL STRESSES |
L. G. Stringer1, R. J. Hayman1, M. J. Hinton1, R.A.Badcock,1 and M. R. Wisnom2
1Mechanical Sciences Sector, DERA, Farnborough, Hants, GU14 0LX, U.K.
2Department of Aerospace Engineering, University of Bristol, Queens Building, University Walk, Bristol, BS8 1TR, U.K.
| Summary | Residual stresses during the cure of thick fibre reinforced composites can lead to delamination cracking and distortion of fibres during component manufacture. Residual stresses are generated by anisotropic thermal expansion behaviour, and also by chemical shrinkage of the resin. This is the second of two complementary papers. Part I described the development of a theoretical model to predict the level of residual stress during the composite cure process. Part II outlines some of the experimental techniques being used to validate the model and to incorporate further refinements (including modelling of the resin cure kinetics). Finally, progress in developing fabrication processes for managing the cure stresses without incurring delamination is presented. The fabrication processes investigated were filament winding and resin transfer moulding. The same materials, E-glass fibres and MY750 epoxy resin, were used for each. |
Keywords | residual stresses, residual strains, epoxy cure, delamination, filament winding, RTM, cure kinetics, Bragg gratings, Di-electric sensors. |