Skip to Main Content
Plastic deformation affects the hysteretic magnetic properties of steels because it changes the dislocation density, which affects domain-wall movement and pinning, and also because it places the specimen under residual strain. An earlier paper proposed a model for computing hysteresis loops on the basis of the effect of grain size d and dislocation density ζd. In that paper, hysteresis loops were compared that all had the same maximum flux density Bmax. The result was that coercivity Hc exhibited a linear relationship with inverse grain size (1/d) and ζd12/. The same was true of hysteresis loss WH. If one compared hysteresis loops all with the same Hmax, these linear dependences were only approximately found. Because the relationships are simpler for loops of constant Bmax, core loss experimenters compare loops that all have the same Bmax. In this paper, we modify the model to study the effect of plastic tensile deformation on hysteresis loops with the same Bmax. We found linear relationships between Hc and residual plastic strain εr and between WH and εr. With increasing residual tensile strain, Hc increases (whereas with increasing elastic tensile strain, Hc decreases). Also, with increasing residual tensile strain, the slope of the hysteresis loop decreases (whereas with increasing elastic tensile strain, the slope increases). We also consider the effect of compressive plastic deformation.