Fe-Ni thin ribbons prepared by an electroplating method

Recently, size-reduction of magnetic devices is strongly required, and it is well-known that an increase in driving frequency is one of methods to reduce the size of the devices. For high frequency driving of the devices, we need to reduce eddy current loss in the cores. Since the eddy current loss is strongly affected by the thickness of the core, the reduction in the thickness is effective to reduce the eddy current loss. Although typical magnetic thin ribbons, such as amorphous or nano-crystallized ones, are prepared by the rapid quenching methods, very thin ribbons (<; 10 μm) is not easy to obtain by the quenching methods. Therefore, we focused on electroplating methods since the thickness of the ribbon can be easily varied by the control of the plating time. In this study, we prepared Fe-Ni thin ribbons prepared by an electroplating method, and evaluated high frequency properties of a toroidal core made from the Fe-Ni thin ribbons.