Dependence of Magnetic Susceptibility on Dislocation Density in Tensile Deformed Iron and Mn-steel

Dependence of the coefficient c of magnetic susceptibility on dislocation density was investigated in tensile deformed polycrystalline Fe and Mn-steel (JIS SFVQ-1A). The dislocation density was measured by transmission electron microscopy (TEM). The coefficient c was analyzed from hysteresis loops, and found to be proportional to dislocation density. It is concluded that the observed dependence of c is valid when there exist homogeneously distributed dislocations. The observed dependence of c on dislocation density would be useful for nondestructive evaluation of dislocation structure in practical steel.