MAGNETOSTRICTION AND APPLICATIONS OF 6.5-PERCENT SI STEEL SHEET

6.5% Si steel is widely known as an excellent soft magnetic material because its magnetostriction is nearly zero. The ac magnetic properties and magnetostriction of 6.5% Si steel sheet were evaluated and compared with those of conventional 3% Si steel sheet. From these data, this sheet is considered to be one of the best core materials available for audio frequency transformers. Toroidal and laminated-type transformers were made from both 6.5% steel sheet and grain-oriented Si steel sheet and the iron losses and noise were investigated. The results indicate that it is possible to operate at high induction, which suggests that this size of a transformer can be reduced by using 6.5% Si steel sheet.