Prediction and compensation of process-induced distortions for L-shaped 3D woven composites

Abstract

A physics-based numerical model for prediction and compensation of the process-induced distortion of 3D woven composite (3DWC) is presented. A new tool-part interaction modelling method for the Resin Transfer Molding process is developed, in which the nonlinear material properties and non-thermoelastic distortion are taken into account. Flat and L-shaped 3DWC parts were fabricated and the process-induced distortions were evaluated. Adopting the input values determined by the warpages of flat parts, the spring-in of L-shaped parts predicted by the model is consistent with the experimental measurements. Based on the model, it is found that taking the warpage/spring-in of the uncompensated parts as the compensation value will result in a deviation between the manufactured parts and the nominal shape. An improved comprehensive compensation procedure is proposed and applied to an L-shaped 3DWC part. The result shows that the dimensional precision of the part can be significantly improved by the compensation process.