Acoustic emission localization in thin multi-layer plates using first-arrival determination

Acoustic emission localization in thin multi-layer plates using first-arrival determination

Článek WoS

In the case of thin plates, there exist two modes of propagation which travel at different velocities and exhibit dispersion characteristics. Techniques that are based on Gabor wavelet transform or cross-correlation technique are commonly used to locate acoustic emission (AE) events which occur in large plates. Due to side-edge reflections and short source-to-sensor distances, these techniques are not suitable for small plate-like specimens. If the thickness of the plate-like specimen is smaller than a specific value, the first-coming (extensional) mode will show non-dispersive behavior in AE frequency range. Under such a condition, the conventional localization method can be used for detecting first-arrival times on non-dispersive extensional mode. In previous paper, authors of the paper developed a first-arrival automatic determination technique based on Akaike information criterion (AIC) for thin metal plates. This paper compares this technique with another AIC approach, STA/LTA method (short-term average/long-term average) and a standard threshold-crossing technique. The comparative analysis includes blind tests, and is provided on four datasets recorded by a four-channel recording system. The three of four datasets were generated using two types of artificial AE sources (Hsu-Nielson source and laser impulse), while the fourth one contains real-measurement data. Each dataset corresponds to measurement made on a thin-plate specimen of a different material or geometry.

In the case of thin plates, there exist two modes of propagation which travel at different velocities and exhibit dispersion characteristics. Techniques that are based on Gabor wavelet transform or cross-correlation technique are commonly used to locate acoustic emission (AE) events which occur in large plates. Due to side-edge reflections and short source-to-sensor distances, these techniques are not suitable for small plate-like specimens. If the thickness of the plate-like specimen is smaller than a specific value, the first-coming (extensional) mode will show non-dispersive behavior in AE frequency range. Under such a condition, the conventional localization method can be used for detecting first-arrival times on non-dispersive extensional mode. In previous paper, authors of the paper developed a first-arrival automatic determination technique based on Akaike information criterion (AIC) for thin metal plates. This paper compares this technique with another AIC approach, STA/LTA method (short-term average/long-term average) and a standard threshold-crossing technique. The comparative analysis includes blind tests, and is provided on four datasets recorded by a four-channel recording system. The three of four datasets were generated using two types of artificial AE sources (Hsu-Nielson source and laser impulse), while the fourth one contains real-measurement data. Each dataset corresponds to measurement made on a thin-plate specimen of a different material or geometry.

arrival time, acoustic emission, localization, Akaike information criterion, thin plate

arrival time, acoustic emission, localization, Akaike information criterion, thin plate

SEDLÁK, P.; HIROSE, Y.; ENOKI, M.

2016

03.02.2013

Elsevier

0888-3270

MECHANICAL SYSTEMS AND SIGNAL PROCESSING

36

2

Spojené království Velké Británie a Severního Irska

636

649

14