Magnetic properties of surface layers of Fe71.5Si15.5−xCu1Nb3B9Alx(x=0,1,2,3 at%) alloys with substitutions by aluminium

Abstract In this paper we describe the influence of the composition and the annealing treatment on the domain structure of Fe–Si–Cu–Nb–B–Al alloys with different Al/Si content. Our observations were compared with the bulk and surface layer coercivity. We have found that aluminium influences magnetic properties and the domain structure of these alloys. Since the crystallization temperature of these alloys decreases with increasing Al content, our samples did not show any improvement of soft magnetic properties as compared with Finemet.