Single sheet tester having open magnetic path for measurement of magnetostriction of electrical steel sheet

A single sheet tester having closed magnetic path (a closed type of SST) ha s a problem that measurement accuracy of magnetostriction is considerably a ffected by electromagnetic force between specimen and yoke, Therefore, an o pen type has been developed. In order to get uniform flux distribution in s ufficiently large region, a compensating magnetizing winding is installed, and a method of waveform control is investigated, in which applied voltages to main and compensating windings are adjusted individually. The effective ness of the newly developed open type is demonstrated by measuring magnetos trictions of thin amorphous sheet as well as highly grain-oriented silicon steel sheet.