A Quantitative Study of the Stabilization Field for 180° Walls in Iron Single Crystal Sheets Containing Solute Nitrogen

The strength of the stabilization field for 180° walls in [100] (011) iron single crystal sheets is derived theoretically and compared with experimental results. An initial magnetization curve after the stabilization of domain walls has taken place is derived using a model in which the reversible and irreversible magnetization processes are separately taken into account. The theoretical maximum value of the stabilization field is shown to be equal to the magnetic field at which the initial magnetization curve shows a first sudden discontinuous increase in induction. Effects of domain wall orientation and magnetostriction on the strength of the stabilization field are calculated. Calculations show that the 180° walls parallel to the (011) plane can be displaced irreversibly at the weekest magnetic field. These theoretical results are satisfied by experiment. A breakaway motion of domain walls is proposed for the sudden discontinuous increase in induction in the stabilized initial magnetization curves. The flexibility of domain walls contributes to the breakaway motion of domain walls.