Cutting Edge of Molding Techniques of Composite Materials

III: Recent in-situ monitoring methods of FRP molding process and their applications

Abstract

In-situ monitoring methods of FRP (Fiber Reinforced Plastics) molding process have been developed in recent 20 years. The present paper describes the recent developments of dielectric/electrical measurement, ultrasonic measurement and optical fiber sensors for in-situ process monitoring of FRP. These sensors can be utilized for monitoring resin impregnation, cure and cooling process of FRP molding. The recent trends of the in-situ process monitoring are measurements of flow-front of liquid resin, degree-of-cure, curing shrinkage, complex stiffness, gelation and vitrification of matrix resin, and process-induced strain and dimensional accuracy of FRP parts. The measured information in FRP during molding process is used to create an accurate model for process simulation and optimize molding process parameters.