New Approach in Process Monitoring of Vacuum Assisted Resin Infusion Process (VARI)

Abstract

Non destructive quality assurance of CFRP parts is a very important item when producing structural aircraft components for military or civil application. Nevertheless, manufacturing and inspection costs have to be reduced on account of economical reasons. Therefore, Liquid Resin Infusion processes for infiltration of dry textile performs are going to be established in the commercial aircraft industry as an alternative to prepreg processes. Besides cost effectiveness due to its physical accessibility the infusion process offers new opportunities for on-line quality assurance, ƒ{ hence, all critical process parameter are known. A new and innovative approach for on-line monitoring of vacuum assisted resin infusion (VARI) processes using optical LockIn thermography is lined out. Fundamental investigations on monitoring of resin flow front are carried out. Several experiments demonstrated that optical LockIn thermography is suitable for characterising the unsteady infusion process. Furthermore, resin front propagation and velocity are determined by analysing the temperature pattern monitored during the infusion process.