Thermoset filament winding process model and parametric study

Filament winding offers great promise for manufacturing composite structures at reduced cost. A key manufacturing concern is selecting materials and processing conditions to ensure final part quality. A model of the filament winding process for wet winding of thermosetting matrix composites was developed. The model relates the processing conditions, part geometry, and material properties to the final part quality. Processing conditions include winding angles, winding speed, temperature and tow tension. Material properties include resin kinetics and rheology, mandrel mechanical and thermal properties, and composite mechanical and thermal properties. Measures of final part quality include: stress and strain in the cylinder during cure and after mandrel removal, final degree of cure, and final fiber volume fraction of each layer. The effects of processing conditions on void size are also determined. The model was validated by comparing model predictions of temperature and strain during winding with experimental data. Once validated, the model was used to study the effects of resin mixing between layers and void volume fraction on final fiber volume fraction. Of the possible quality measures, final fiber volume fraction was selected because it is critically related to the final strength of the cylinder. The results of the parametric study presented indicate that resin mixing and void content significantly affect the fiber volume fraction. Model results shown also suggest that parameters which affect the resin viscosity and flow, such as resin rheology, gel point, and fiber bed permeability, must be well defined in order to obtain accurate model predictions.