Measurement and Analytical Modeling of the $\Delta E$ Effect in a Bulk Iron-Cobalt Alloy

The Young modulus E of a material is the ratio between an uniaxial applied stress and the elastic strain measured in the direction parallel to the applied stress. For magnetic materials, stress-strain relationship appears to be non-linear. This effect is called the ΔE effect, usually introduced as a dependency of the Young modulus on the stress level, but physically due to a re-organization of the magnetic domains under stress generating a magnetostriction strain. In this paper, the ΔE effect is measured for a bulk iron-cobalt alloy thanks to two different methods. An analytical magneto-mechanical modeling of the ΔE effect is finally applied and compared to the experimental results.