AC magnetic losses in Bi-2223/Ag tapes with different aspect ratios

AC losses in multi-filamentary tapes depend on various parameters. Among them, the overall tape width and thickness are expected to have ail important influence. In order to study this geometrical effect, five Bi-2223/Ag tapes with different aspect ratios from 5 to 26 have been prepared. AC losses have been measured at 77 K when a perpendicular AC magnetic field is applied. It has been found that at any frequencies the magnetic loss per cycle increases as the aspect ratio increases. For AC magnetic loss, with increasing frequency from 3 to 9000 Hz the losses as a function of frequency show a maximum if the field amplitude is much less than the full penetration field or increase continuously if the field amplitude is larger. (C) 2004 Elsevier B.V. All rights reserved.