Theory and application of highly magnetoelastic Metglas 2605SC (invited)

Publisher Website
Google Scholar
Abstract
We show by a variety of experiments that the magnetomechanical coupling k in Metglas 2605SC has larger values than in any other device material. Our Mössbauer experiments show that the anisotropy axis is quite well defined when compared with Metglas 2605CO. The small value of the anisotropy and the well defined axis lead to a value of 7 for the ‘‘ΔE effect,’’ a very large value. By assuming a small vestigial shear stress we derive from basic principles expressions that describe the macroscopic magnetoelastic characteristics of 2605SC. We are able to fit our dynamic coupling factor data with parameters from our static stress measurements. This is the first time such a description has been presented, and we use it to predict the performance of a magnetomechanical strain gage. We show that such a strain gage can have 103 to 105 more sensitivity than a conventional strain gage. We discuss the attempts of other authors to build devices and present prototype device designs. We show that the material has other advantages for devices such as a lack of Barkhausen noise and good low frequency characteristics.