Experimental study of deformation fields under axial tension on composite surface with prestressed carbon tape (original) (raw)
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Composites Part A: Applied Science and Manufacturing, 2007
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The accurate modelling of residual stress in thermoset composites requires comprehensive consideration of all the phenomena contributing to its formation. These include: chemical shrinkage of matrix due to cross linking of molecules, mismatch of thermal expansion or contraction among fibres and matrix and viscoelastic relaxation during the fabrication. Thermo-physical and thermomechanical properties are altered during the curing process due to an exothermic chemical reaction. Since all the phenomena causing residual stress are strongly coupled, the solution procedure is a complex task. In this study, spring-in angle of carbon/epoxy woven composite bracket with three different thicknesses are calculated by simultaneously solving the thermo-kinetics and thermo-mechanics coupling by a finite element code COMSOL Multiphysics. Properties of composites required for numerical simulation are obtained using an analytical method. The spring-in angle values obtained by numerical simulation are also compared with the results of the analytical model.