The comparison and ranking of advanced data processing techniques of thermographic nonde-structive testing (NDT) seems decisive for end users who are required to optimize their NDT tools. This is a difficult task, which explains why there are so few articles dealing with this challenge. Furthermore, these works are often incomplete, since the choice of metrics is too limited and/or inappropriate to an accurate, unbiased ranking. Most of them are based on the number of detected discontinuities among a series of discontinuities of various sizes and depths, and the only assessed metric is the contrast-to-noise ratio of the disconti-nuity signatures. This observation justifies the need for a more thorough comparison, based on the evaluation of several unbiased parameters. In this article, three metrics are considered: not only the contrast-to-noise ratio, but also the sharpness of the discontinuity edges and the accuracy of the identified characteristic dimension of the discontinuity using the contrast full-width at half-maximum. They are assessed for a trio of thermal images of a composite sample with 12 embedded calibrated discontinuities, provided by four different pulse thermographic NDT data processing techniques: thermographic signal reconstruction polynomial coefficient (PC-TSR) technique, pulse phase thermography (PPT), principal component thermography (PCT), and higher order statistics (HOS). The relative compar-ison of the relevance of each of these techniques is then based on 432 discontinuity signatures (4 techniques × 3 images × 12 discontinuities × 3 metrics). In order to simplify the final ranking procedure, it is also shown that this high number of data can be drastically reduced to four numbers.
Almond, D.P., M.B. Saintey, and S.K. Lau, “Edge Effects and Defect Sizing by Transient Thermography,” QIRT 94 Conf., Sorrento, Italy, 1994, Ed. Europe. Therm. & Industrie, Paris, 1995, pp. 247-252, QIRT Open Archives: www.qirt.org, Paper #1994-037.
Almond, D.P., and S.K. Lau, “Edge Effects and a Method of Defect Sizing for Transient Thermography,” Applied Physics Letters, Vol. 62, No. 25, 1993, pp. 3369-3371.
Balageas, D., B. Chapuis, G. Deban, and F. Passilly, “Improvement of the Detection of Defects by Pulse Thermography Thanks to the TSR Approach in the Case of a Smart Composite Repair Patch,” Quantitative Infrared Thermography Journal, Vol. 7, No. 2, 2010, pp. 167-187.
Balageas, D, “Defense and Illustration of Time-resolved Pulsed Thermog-raphy for NDE,” Quantitative Infrared Thermography Journal, Vol. 9, No. 1, 2012, pp. 3-32.
Balageas, D.L., A.A. Déom, and D.M. Boscher, “Characterization and Non Destructive Testing of Carbon-Epoxy Composites by a Pulsed Photothermal Method,” Materials Evaluation, Vol. 45, No. 3,1987, pp. 461-465.
Balageas, D.L, “In Search of Early Time—an Original Approach in the Thermographic Identification of Thermophysical Properties and Defects,” Advances in Optical Techniques, 2013, Article ID 314906, http://dx.doi.org/10.1155/2013/314906.
Balageas, D.L., and J-M. Roche, “Common Tools for Quantitative Time-resolved Pulse and Step-heating Thermography—Part 1: Theoretical Basis,” Quantitative Infrared Thermography Journal, Vol. 11, No. 1, 2014, pp. 43-56.
Duan, Y., P, M. Servais Genest, C. Ibarra-Castanedo, and X.P.V. Maldague, “ThermoPoD: A Reliability Study on Active Infrared Thermography for the Inspection of Composite Materials,” Journal of Mechanical Science and Technology, Vol. 26, No. 7, 2012, pp. 1985-1991.
Ibarra-Castanedo, C., N.P. Avdelidis, and X. Maldague, “Qualitative and Quantitative Assessment of Steel Plates Using Pulsed Phase Thermog-raphy,” Materials Evaluation, Vol. 63, No. 11, 2005, pp. 1128-1133.
Ibarra-Castanedo, C., and X. Maldague, “Pulsed Phase Thermography Reviewed,” Quantitative Infrared Thermography Journal, Vol. 1, No. 1, 2004, pp. 47-70.
Krapez, J-C., D. Boscher, Ph. Delpech, A. Déom, G. Gardette, and D. Balageas, “Time-Resolved Pulsed Stimulated Infrared Thermography Applied to Carbon-epoxy Non Destructive Evaluation,” QIRT 92 Conf., Châtenay-Malabry, France, 1992, pp. 195-200. QIRT Open Archives: http://qirt.gel.ulaval.ca/dynamique/index.php?idD=55, Paper QIRT 1992-029.
Lopez, F., C. Ibarra-Castanedo, X. Maldague , and V. de Paulo Nicolau, “Pulse Thermography Signal Processing Techniques Based on the 1D Solution of the Heat Equation Applied to the Inspection of Laminated Composites,” Materials Evaluation, Vol. 72, No. 1, 2014, pp. 91-102.
Maldague, X., and S. Marinetti, “Pulse Phase Infrared Thermography,” Journal of Applied Physics, Vol. 79, 1996, pp. 2694-2698.
Marinetti, S., E. Grinzato, P.G. Bison, E. Bozzi, M. Chimenti, G. Pieri, and O. Salvetti, “Statistical Analysis of IR Thermographic Sequences by PCA,” Infrared Physics and Technology, Vol. 46, Nos. 1-2, 2004, pp. 85-91.
Rajic, N, “Principal Component Thermography for Flaw Contrast Enhancement and Flaw Depth Characterisation in Composite Structures,” Composite Structures, Vol. 58, No. 4, 2002, pp. 521-528.
Roche, J-M., and D.L. Balageas, “Common Tools for Quantitative Pulse and Step-heating Thermography—Part II: Experimental Investigation,” Quantitative Infrared Thermography Journal, Vol. 12, No. 1, 2015.
Roche, J-M., F-H. Leroy, D.L. Balageas, “Images of Thermographic Signal r Reconstruction Coefficients: a Simple Way for Rapid and Efficient Detection of Discontinuities,” Materials Evaluation, Vol. 72, No. 1, 2014a, pp. 73-82.
Roche, J-M, F-H. Leroy, and D.L. Balageas, “Information Condensation in Defect Detection Using TSR Coefficients Images,” QIRT 2014 Conf., Bordeaux, France, 7-11 July 2014b, QIRT Open Archives: www.qirt.org, Paper QIRT 2014-002.
Shepard, S.M., “Advances in Pulsed Thermography,” Thermosense XXIII, Proc. SPIE, Vol. 4630, No. 511, 2001, pp. 511–515.
Shepard, S.M., J.R Lhota., B.A. Rubadeux, D. Wang, and T. Ahmed, “Reconstruction and Enhancement of Active Thermographic Image Sequences,” Optical Engineering, Vol. 42, No. 5, 2003, 1337-1342.
Usamentiaga, R., P. Venegas, J. Guerediaga, L. Vega, I. López, “A Quantita-tive Comparison of Stimulation and Post-processing Thermographic Inspection Methods Applied to Aeronautical Carbon Fibre Reinforced Polymer,” Quantitative Infrared Thermography Journal, Vol. 10, No. 1, 2013, pp. 55-73.
206 Page Views
0 PDF Downloads
0 Facebook Shares