強磁性構造鋼 A533B および SUS410 の磁気特性と機械的特性の相関

A nondestructive measuring method named the magnetic interrogation method was proposed for assessing material degradation in aged nuclear reactor pressure vessels.The method is based on the correlation between the magnetic and mechanical property changes in the degraded steels. To confirm the feasibility of the method, the correlation between the magnetic and mechanical properties was measured for steels used in nuclear pressure vessels and stainlesss steels fabricated at several temperatures. A good correlation was obtained: the coercivity increases with the Vickers hardness, yield stress, and tensile strength, whereas the maximum permeability decreases. The results can be used for assessing material degradation in steels by the proposed nondestructive means.