Article Article
Defect Mapping Based on Signal Correlation for Ultrasonic NDE

This paper presents the application of a signal correlation technique to automatically classify ultrasonic A-scan signals for defect and non-defect regions in isotropic and anisotropic materials. First, a reference A-scan signal of a non-defect area was generated by autocorrelation and statistics. Next, the similarity between the reference signal and the signal of interest was analyzed based on their cross-correlation. The analyzed result was quantified using the correlation coefficient and the distance between the front and back echoes. After that, the defect mapping was defined based on these two criteria to locate the defect area on a 2D image. This method uses statistics rather than the prior knowledge of an inspector to generate a C-scan map, and has particular value in automated ultrasonic signal classification and characterization.

1. Im, K.H., D.K. Hsu and I.Y. Yang. “Inspection of Inhomogeneities in Carbon/Phenolic Matrix Composite Materials Using NDE Techniques,” Key Engineering Materials. Vol. 270-273, pp. 1799-1805. 2004. 2. Lee, J.H., S.W. Choi, K.S. Kim and J.H. Park. “Nondestructive Characterisation of Carbon/Carbon Brake Disks Using Ultrasonics,” 10th Asia-Pacific Conference on Non-Destructive Testing, Brisbane, Australia, pp. 1109-1112. 2001. 3. Ruosi, A. “Nondestructive Detection of Damage in Carbon Fiber Composites by SQUID Magnetometry,” Physica Status Solidi C - Conferences and Critical Reviews, Vol. 2(5), pp. 1533-1555. 2005. 4. Bray, D.E. and D. McBride. Nondestructive Testing Techniques, John Wiley & Sons, New York. 1992. 5. Data presentation, NDT Resource Center, EquipmentTrans/DataPres.htm. 6. Box, G.E.P., G.M. Jenkins and G.C. Reinsel. Time Series Analysis: Forecasting and Control, Third Edition, Englewood Cliffs, NJ: Prentice Hall. 1994. 7. Poudel, A., R. Kanneganti, L. Gupta and T.P. Chu. “Nearest Mean Classifier for Defect Classification in CFRP Panels,” Proceedings of 22nd Annual ASNT Research Symposium and Spring Conference, Memphis, TN, March 18-21, 2013.
Usage Shares
Total Views
82 Page Views
Total Shares
0 Tweets
0 PDF Downloads
0 Facebook Shares
Total Usage