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Nishimura, Akihiko; Takenaka, Yusuke*; Furuyama, Takehiro*; Shimomura, Takuya; Terada, Takaya; Daido, Hiroyuki
Journal of Laser Micro/Nanoengineering, 9(3), p.221 - 224, 2014/11
Times Cited Count:0 Percentile:0(Nanoscience & Nanotechnology)Heat resistant FBG sensors were developed by femtosecond laser processing to apply them to high temperature operated piping system of nuclear power plants. The FBG sensor was installed on the surface of a steel blade and a vibration test was conducted to detect the resonant vibration frequency of the vibrating blade. The FBG sensor had the heatproof performance at 600C. A frequency stabilized sensing system using a tunable laser was tested for structural health monitoring in daily operation of nuclear power plants. The FBG sensor was installed on the surface of a steel blade for vibration induced strain measurements. Welding, brazing, soldering and noble metal powder adhesive were discussed for molding the FBG sensors.
Nishimura, Akihiko; Terada, Takaya; Takenaka, Yusuke*; Furuyama, Takehiro*; Shimomura, Takuya
Proceedings of 22nd International Conference on Nuclear Engineering (ICONE-22) (DVD-ROM), 6 Pages, 2014/07
Since 2007, JAEA has been developing laser based technologies of structural health monitoring. The FBG sensor made by femtosecond laser processing will be the best candidate. To make the best use of the heat resistant characteristic, the FBG sensor was embedded in metal mold by laser cladding. A groove was processed to the surface of a SUS metal plate. We used a QCW laser to weld a filler wire on the plate. A series of weld beads perfectly formed a sealing clad on the groove. Though the FBG sensor was buried tightly, no degradation on the reflection spectrum was detected after the processing. The FBG sensor could detect the vibration of the plate caused by impact shocks and audio vibration. The reflection peak of the FBG sensor under laser cladding condition was shifted to be 6 nm. We demonstrated that the corresponded temperature derive from the reflection peak shift reached 600 degrees in heat shock experiments. The installation procedure of a FBG sensor using a portable laser cladding machine was described.
Nishimura, Akihiko; Takenaka, Yusuke*; Furuyama, Takehiro*; Shimomura, Takuya; Terada, Takaya; Daido, Hiroyuki
Proceedings of 1st Smart Laser Processing Conference 2014 (SLPC 2014), 4 Pages, 2014/04
Heat resistant FBG sensors were developed by femtosecond laser processing. In order to apply them to piping system of nuclear power plants, vibration test under high temperature was demonstrated. The FBG sensor had the heatproof performance at 600C. A frequency stabilized sensing system using a tunable laser was tested for structural health monitoring in daily operation of nuclear power plants. The FBG sensor was installed on the surface of a steel blade for vibration induced strain measurements. Welding, brazing, soldering and noble metal powder adhesive were discussed for molding the FBG sensors.
Nishimura, Akihiko; Terada, Takaya; Yamada, Tomonori; Takenaka, Yusuke*; Furuyama, Takehiro*
no journal, ,
We are developing the inspection technology for laser micro spot welding. Butt welding for the inner wall of heat exchanger tubes were successfully carried out by a composite-type optical fiber scope. The related technologies are the following: (1) Rapid inspection by eddy current testing (2) Fiber endoscope observation (3) Synchrotron X-ray absorption contrast method. These technologies are versatile to be applied in maintenance for industrial production plants.
Nishimura, Akihiko; Terada, Takaya; Takenaka, Yusuke*; Furuyama, Takehiro*; Shimomura, Takuya; Ioki, Kimihiro*
no journal, ,
no abstracts in English
Kitsunai, Daisuke; Furuyama, Takehiro*; Nishimura, Akihiko; Yamamoto, Shunya
no journal, ,
no abstracts in English
Daido, Hiroyuki; Abe, Hiroshi; Shobu, Takahisa; Shimomura, Takuya; Tokuhira, Shinnosuke*; Takenaka, Yusuke*; Furuyama, Takehiro*; Nishimura, Akihiko; Uchida, Hirohisa*; Oshima, Takeshi
no journal, ,
no abstracts in English
Nishimura, Akihiko; Furuyama, Takehiro*; Ito, Fuyumi*; Ito, Chikara; Naito, Hiroyuki; Oba, Hironori; Yamamoto, Shunya; Wakaida, Ikuo; Sugiyama, Akira
no journal, ,
no abstracts in English