On the origin of essential differences in the coercive force, remanence, and initial permeability of ferromagnetic steels in the loaded and unloaded states upon plastic tension

The behavior of remanence M r, initial permeability μ, and coercive force H c of the steels during their plastic tension in both loaded and unloaded states upon “slow” and “rapid” loading is explained from a unified point of view. It is shown that (1) a sharp (severalfold) decrease in M r and μ and a similar abrupt increase in H c are caused by the same effect, namely the appearance of high residual compressive stresses in most grains along the force direction; (2) in the loaded state, M r and μ slowly decrease and H c similarly slowly increases with increasing degree of deformation ε due to a common effect of increasing dislocation density ρ with increasing ε; (3) the values of M r, μ, and H c in the transition region, in which ε ≤ εcr, substantially differ from each other upon “slow” and “rapid” loadings; (4) at ε ≥ εcr, the dependences of the M r, μ, and H c parameters on ε both in the loaded and unloaded states are parallel to each other.