The effect of surface layers on power loss in amorphous ribbon materials

Loss measurements were carried out on as-cast, polished and unpolished annealed Metglas 2605SC amorphous ribbon using the initial rate of rise of temperature technique. The samples were magnetised from 0.8 to 1.4 Tesla in the frequency range of 50 to 400 Hz. The lowest loss was detected for annealed samples polished on both sides. This reduction in power loss is attributed to the reduction in the inhomogeneity of element concentration across the ribbon thickness. The area in the middle of the ribbon has a more uniform element concentration than the areas near surfaces. The anomaly factor which shows a comparison between the loss components also clarified the inhomogeneity across the ribbon thickness