AE Source Localization in a Steel Plate with the Dispersive o Mode based on the Cross-Correlation Technique and Time Reversal Principle.

The accuracy of damage localization, especially the accurate determination of the time arrival difference, is important in the field of acoustic emission (AE) source localization. In this paper, we propose a new approach to localize an AE source with the dispersive A_o mode. For this approach, we analyzed the cross correlation of AE signals with a reference database and determined the time lag of A_o mode. The technique is carried out in a twostage computational process. First, AE signals are used to construct the reference database and compensate for the dispersion of waves based on the time reversal principle. Second, the time arrival difference of the A_o mode is determined by the cross correlation of AE signals with the reference signals using the first threshold-crossing technique. A localization algorithm is carried out based on the triangulation technique. The proposed approach is conducted on a steel plate with three AE sensors coupling on the surface. Pencil-lead breaks are adopted to simulate AE sources. Results indicated that eight verification points were successfully localized with the maximum and minimum relative errors of 0 .9 8% and 0 .58% , respectively. Thus, this paper shows an optional technique to localize AE sources with the A_o mode, which is of significant importance. [ABSTRACT FROM AUTHOR]