Baseline-free Ultrasonic Crack Evaluation in a Welded Joint Structure.pdf

1、This paper proposes a stripe-PZT sensor-based baseline-free crack diagnosis technique in the heat affected zone (HAZ) of a structure with a welded stiffener.The proposed technique enables to identify and localize a crack

2、 in HAZ using only current data measured using a stripe-PZT sensor.The main achievements of this paper are stated as follows:
　　First，a new crack detection system named stripe-PZT sensor is developed by the author gro

3、up.The use of the stripe-PZT sensor makes it possible to significantly improve the applicability to real structures and minimize man-made errors associated with the installation process by embedding multiple piezoelectri

4、c sensors onto a printed circuit board.
　　Moreover，a new frequency-wavenumber (f-k) domain analysis-based baseline-free
　　crack diagnosis algorithm-minimizes false alarms caused by environmental variations by avoid

5、ing simple comparison with the baseline data accumulated from the pristine condition of a target structure is developed corresponding to the stripe-PZT sensor.
　　The proposed technique is numerically as well as experi