Improved non-destructive testing of carbon fiber reinforced polymer (CFRP) composites using pulsed thermograph

Pulsed thermography (PT) is a popular non-destructive testing (NDT) technique for defect detection in carbon fiber reinforced polymer (CFRP) composites. However, non-uniform backgrounds commonly observed in thermal images often reduce the detection power of PT. For background removal, mathematical morphology (MM), originally proposed for the analysis of geometrical structures, is adopted in this paper. After noise reduction, the non-uniform backgrounds in each image are conveniently constructed by MM. By subtracting the backgrounds from the original data, improved NDT is achieved. Experiment results show the effectiveness of the proposed method, where the defects in the CFRP specimen are more clearly identified.