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Furusawa, Akinori; Nishimura, Akihiko; Torimoto, Kazuhiro; Takenaka, Yusuke*; Saijo, Shingo*; Toyama, Ryoji*
no journal, ,
The aim of this work presented here is to investigate the applicability of the guided wave testing to detect and evaluate the quality of laser beam butt welding line. First, four test pipes were prepared. All of the pipes were laser beam butt welded from inside of the pipe using laser torch. Two pipes of them were high-quality welded, the others were low-quality. Two different pipe-wall-thicknesses were in each quality. Secondly, Laser beam butt welding line detection and the quality evaluation experiments were performed. T(0,1) mode guided wave was excited and received by electromagnetic acoustic transducer array. Finally, the experimental results were analyzed and issues concerning with the applicability of the guided wave testing to detection and quality evaluation of the laser butt welding line were discussed.
Furusawa, Akinori; Nishimura, Akihiko; Torimoto, Kazuhiro; Takenaka, Yusuke*
no journal, ,
This paper is concerning with non-destructive evaluation of the concrete construct using laser excited ultrasonic. Laser ultrasonic excitation and receiving experiments are performed and the resulting ultrasonic wave forms are analyzed as compared with simulation ones. Issues concerning with the applicability are discussed.
Furusawa, Akinori; Nishimura, Akihiko; Torimoto, Kazuhiro; Takenaka, Yusuke*; Toyama, Ryoji*; Nakamoto, Hiroyuki*
no journal, ,
The aim of this work presented here is to investigate the applicability of ultrasonic guided wave for evaluation of laser beam butt welding quality. First, laser beam butt welded pipes are prepared. Two pipes are jointed and continuous wave laser beam is irradiated on the line. The test pipes are divided into two groups according to the difference in laser welding quality. One group is fine quality welded, another group is poor. Second, ultrasonic guided wave testing experiment is performed on the pipes. Torsional mode guided wave is excited by Electromagnetic Acoustic Transducers. Finally, the experimental results are analyzed and issues are discussed. The reflection wave bullet from the poor welded line is clearly observed, whereas no reflection from fine welded line. It is found that the ultrasonic guided wave technologies have the potential for laser beam butt welding line evaluation.
Furusawa, Akinori; Nishimura, Akihiko; Takenaka, Yusuke*
no journal, ,
The purpose of this work is to develop ultrasonic methodology of detecting corrosion of the steel bar embedded in concrete. Irradiating pulse-laser beam at the bottom of the corroded steel bar embedded in concrete generates ultrasonic propagating the bar to be measured at another bottom. The corroded steel bar embedded in concrete is made by electrical corrosion method. Comparing waveforms of the corroded steel bar and of the sound one, issues concerning with the different waveforms are reported.