Prediction of Process-Induce Distortions and Residual Stresses of Ancomposite Suspension Blade

This paper deals with a universal simulation strategy for the calculation of process-induceddistortions and residual stresses of a composite part. The mechanical material behavior is describedby a viscoelastic material model depending on temperature and degree of cure . The required materialparameters are derived by dynamic mechanical analyses. For the description of the reaction kinetic aphenomenological based model considering chemical and diffusion-controlled reactions is introduced.The reaction model parameters are fitted to isothermal and dynamic DSC measurements via globaland local optimization. The thermal expansion and chemical shrinkage are characterized by thermalmechanical analysis and using the contact angle measurement method. The simulation strategy isdemonstrated for a GFRP suspension blade for the automobile industry. Based on a sequential coupledtemperature-displacement analysis thermal hot spots, temperature and degree of cure distributions aswell as the final corresponding process-induced distortions and residual stresses are calculated andanalyzed. The development of the stiffness and the correlated stress during the curing process arediscussed in more detail. Furthermore, the effect of a degree of cure dependent stiffness on the stressesis investigated.