Magnetic nondestructive evaluation of degradation of nuclear pressure vessel steels due to mechanical loading

Issue title: Proceedings of the tenth International Symposium on Applied Electromagnetics and Mechanics ISEM-Tokyo

Article type: Research Article

Authors: Sukegawa, T.^{a; *} | Uesaka, M.^a

Affiliations: [a] Nuclear Engineering Research Laboratory, Graduate School of Engineering, The University of Tokyo, 2-22, Tokai, Naka, Ibaraki, 319-1106, Japan

Correspondence: [*] Corresponding author: Toshio Sukegawa; Tel.: +81 29 287 8917; Fax: +81 29 287 8488; E-mail: [email protected]

Abstract: We performed magnetic nondestructive evaluation of degradation of nuclear pressure vessel steels due to mechanical loading as a fundamental research. We measured magnetic properties of low alloy steel samples, which were degraded due to tensile and cyclic loads. Magnetic hysteresis curves change depending on the loading conditions. The changes of the coercive force, residual magnetic flux density and permeability were obtained and analyzed in details as a function of the residual strain. Based on the above results, we performed the sensitivity analysis of magnetic property changes for the mechanical load. Finally we concluded that the incremental permeability at H = 0 is the most sensitive index for early degradation due to the mechanical loads. The feasibility of application of this magnetic technique to the evaluation of degradation due to neutron mechanical and thermal loading is now under consideration.

DOI: 10.3233/JAE-2002-467

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 15, no. 1-4, pp. 315-321, 2002