TY - JOUR
TI - Defect detection of GFRP laminates by barker code modulation excitation infrared thermal imaging
AU - Tang Qing-Ju
AU - Ran Ling
AU - Qu Ze-Shen
AU - Bu Chi-Wu
JN - Thermal Science
PY - 2023
VL - 27
IS - 1
SP - 447
EP - 454
PT - Article
AB - During the preparation and service of GFRP laminates, due to the influence of  manufacturing process, it is easy to produce debonding defect. This paper  expounds the basic principle and test process of infrared nondestructive  testing, which using the barker code modulation of the thermal wave to  identify the GFRP laminate debonding defect. Through the establishment of  infrared thermal imaging testing system, this paper studies its detection  effect on defects with different diameter, depth and diameter-to-depth  ratio, processes the image sequence by using principal component analysis  (PCA) and discrete Fourier transform (DFT) algorithms, and finally  calculates and compares the processed signal-to-noise ratio (SNR). The  results show that Barker code modulated thermal wave infrared detection can  detect the debonding defects of GFRP laminates. Among them, the detection  effect of 13-bit Barker coded modulation excitation is better, and the image  processed by DFT has better recognition effect.