Examination of Measurement Method for Magnetostriction of Electrical Steel Sheet with Lock-in Amplifier

Abstract

It is important to measure magnetostriction under mechanical stress in order to clarify the relationships between magnetic property and stress. However, it is difficult to measure the magnetostriction of the electrical steel sheet because the quantity of the magnetostriction is very small. In this paper, we examine measurement method with a lock-in amplifier to improve the measurement accuracy of magnetostriction. From the result, the lock-in amplifier is very useful to measure the magnetostriction of the electrical steel sheet in comparison with a commercial strain amplifier.