Experimental study on defects detection in GFRP laminates using lock-in infrared thermography technology

Abstract

To detect the debonding defect of glass fiber reinforced polymer (GFRP) laminate, the lock-in infrared thermography non-destructive testing system is built and the systematic testing research are conducted, and the effect of different geometrical parameters of debonding defects on the testing results are analyzed. Algorithms such as inter frame differential-multi frame cumulative average method, polynomial fitting-correlation coefficient method, and time-difference contrast method are used to process the image sequence, and signal-to-noise ratio and information en-tropy are defined as the parameters for evaluating the performance of algorithms.