ONLINE INTELLIGENT CURE MONITORING FOR AEROSPACE APPLICATIONS

Abstract

The constant growth rates in the field of fiber composite materials show a potential that has been rising for years. Fiber composite materials are contributing to this growth. Above all, autoclave and resin transfer molding (RTM) processes for the production of large components and high-volume components for the aerospace industry have become essential in the area of fiber composite construction. Therefore high quality and safety requirements apply to the products produced, as well as a continuous need for economic efficiency improvement for components and processes. The detection of these components and process-relevant information is one of the key points for improving quality and efficiency. An intelligent process monitoring system has been employed for the in-situ monitoring of composite aerospace structure manufacturing. The simultaneous measurement of the resin’s temperature and electrical resistance allows for real-time prediction of viscosity, degree of cure, glass transition temperature (TG) and deviations in mixing ratio. The correlation between electrical resistance, viscosity and degree of cure evolution of widely used aerospace resins proves the accuracy and repeatability for the cure prediction up to the end-of-cure. Due to the different application areas a common ultrasonic system was used. It will discuss how the measurement data of both methods can be correlated and supported.