Abstract
Dependences of two magnetic parameters, coercive field Hc and coefficient c, on dislocation density were investigated in tensile deformed Fe polycrystal and SFVQ-1A commercial steel. The dislocation density was measured by using transmission electron microscope (TEM). Magnetic parameters were analyzed from hysteresis loops. Coercive field Hc and coefficient c were proportional to ρ1/2 and ρ, respectively. These parameters have simple dependences on dislocation density, and would be useful for nondestructive evaluation of dislocation structure in commercial steel.