Improvement of magnetic flux density measurement technique for irradiation damage evaluation

Konno, Shotaro; Takaya, Shigeru  ; Nagae, Yuji ; Yamagata, Ichiro ; Ogawa, Ryuichiro; Akasaka, Naoaki; Nishinoiri, Kenji

We are developing a method for evaluation of irradiation damage on structural materials in nuclear plants by using change in magnetic flux density due to irradiation damage. In this study, the magnetic flux density measurement technique has been improved by introducing a new magnetizer which enables local magnetizing by contacting the sample surface, and the calibration method of the flux gate sensor for the magnetic flux density. We can magnetize samples, especially ferromagnetic samples, more precisely compared to the existing method. Furthermore, the new method can remove many limitations for the application to real plants.