An investigation by Auger and laser acoustic microscopy of the bond between layers of consolidated amorphous ribbon (Powercore)

Abstract

It has been found possible to consolidate layers of amorphous ribbon to produce a thick strip which does not require annealing, and has similar magnetic properties to those of the much thinner ribbon. The reduced importance of eddy current losses that this implies must be due to the nature of the bond between the layers of ribbon. An extensive investigation of this bond has been carried out using Auger microscopy and laser acoustic microscopy. These show that bonding is localized and invokes local plastic low into ribbon irregularities, and the probable formation of a silicon oxide “glue”. These explain the low eddy current losses and the improved pack factor of the strip compared to that of the starting ribbon. The uniformity of both mechanical and magnetic properties is also improved. Successful trials of the strip have been undertaken, This work has been jointly funded by the Electric Power Research Institute (EPRI) and Allied Corp.