Effect of horizontal shift between fabric layers on the meso-scale-void formation in liquid composite molding

Abstract

Accurate prediction of void content is the foundation of process optimization for Liquid Composite Molding (LCM). During mold filling, void formation is a three-dimensional flow process, while at present the void formation is treated as a result of in-plane air entrapment, the resin and air flows on the thickness direction are totally neglected. In this paper, resin flows in the adjacent layers are considered to analyze the three-dimensional air entrapment and the meso-scalevoid formation. Firstly, the horizontal shift between fabric layers is analyzed, the mesopore coverage modes under different shift states are summarized. Then based on the mathematical models of micro and meso flows, the three-dimensional void entrapment processes under different cladding flow modes are studied in detail, a mathematical model for the prediction of meso-scale-void formation is established. Finally, a series of mold filling and void measurement experiments are carried out to verify the above model.

Keywords

• Polymer composites
• Liquid composite molding
• Void formation
• Modeling and simulation