2008 年 48 巻 4 号 p. 461-466
Magnetic properties are compared with total dislocation density that considered the dislocation structure change comprehensively in tensile and fatigue deformed commercial steels. Coercive field increases little with the fatigue cycles and seems to be saturated in the middle and last stages of metal fatigue. The coefficient of magnetic susceptibility c increases over all stages of the fatigue tests and is sensitive to degradation in comparison with HC. These properties are influenced from total dislocation density, and independent on deformation way. The magnetic-structure-sensitive properties would be useful for evaluation of dislocation structure change, and applied nondestructive evaluation method with development of the correct B–H curve measurement way.