Saturation magnetization distribution in the vicinity of a grain boundary in a plate of a triaxial silicon-iron-type ferromagnet

Influence of grain boundaries on orientation of spontaneous magnetization inside domains in the Fe-3%Si ferromagnetic sheets

“…This is quite correct for the distances x 1 µm across the grain boundary, which exceed a mean distance between dislocations inside the boundary [8]. The main complication connected with the solution of equation ( 3) is the computation of the magnetostatic field H m at the grain boundary, which fulfils the equation [1,3,5]…”

“…The grain boundaries play an important role in the formation of magnetic properties and domain structure of polycrystalline ferromagnetics [1][2][3]. In particular, net magnetization and core losses inside grains in grain-oriented silicon steel sheets become inhomogeneous [4][5][6]. One of the main reasons of this influence, parallel with varying texture from grain to grain [4], is magnetostatic field H m , generated by the grain boundaries [1,2,4].…”

“…One of the main reasons of this influence, parallel with varying texture from grain to grain [4], is magnetostatic field H m , generated by the grain boundaries [1,2,4]. Under the H m action, the vectors M S can deviate from the easy directions near the grain boundaries (µ * -effect) even in materials of Fe-3%Si type with comparably large magnetic crystallography anisotropy constant K 1 [1,5,6]. Previously, an appearance of such magnetostatic effects near the grain boundaries was expected also in saturated state [5].…”

“…Under the H m action, the vectors M S can deviate from the easy directions near the grain boundaries (µ * -effect) even in materials of Fe-3%Si type with comparably large magnetic crystallography anisotropy constant K 1 [1,5,6]. Previously, an appearance of such magnetostatic effects near the grain boundaries was expected also in saturated state [5]. Figure 1 shows, obtained by us, Kerr images of domain structure of grain-oriented silicon steel sheets near the grain boundary, which divides crystallites with different orientation of the easy axis 100 .…”

“…An equilibrium distribution of M S (x) (and so, dependence z(x)) can be found as the established solution (at t → ∞) of the Landau-Lifshitz equation [1,3,5]:…”