Prediction of manufacturing process of composite structural components

X-ray CT image of a GF/PP injection molded component. White lines are short glass fibers.

This study proposes a numerical analysis for predicting fiber motion during injection molding of short-fiber-reinforced composites using the moving particle semi-implicit (MPS) method. Its meshless and Lagrangian nature enables us to track individual fibers and to easily represent free surfaces. In this study, the mechanism of fiber orientation was investigated experimentally and numerically. The prediction agreed well with the experiment, and the associated mechanism of fiber orientation is discussed. Furthermore, this approach explicitly demonstrates the interaction between fibers, which is an advantage of the proposed approach.

Although resin transfer molding is promising for manufacturing aircraft structural components, formation of micro- and macro- voids is a technical issue. Voids may cause degradation of strength and stiffness. Therefore, we are developing a simulator that predicts resin flow, impregnation of resin into fiber base material, and formation of voids. Through prediction and experiments on resin impregnation process, we aim to clarify the formation mechanism of microstructure including micro-voids and to propose optimization method of molding conditions.