MAGNETORESISTORS AS A TOOL FOR INVESTIGATING THE MECHANICAL-PROPERTIES OF FERROMAGNETIC MATERIALS

We have investigated the possibility of applying the Villari effect fo r measurements of the dependence of deformation on the external loadin g. The magnetic field arising due to the deformation has been measured with a Permalloy magnetoresistive sensor. The plot of the dependence of the external field H on the strain epsilon agrees almost perfectly with the classical dependence sigma=f(epsilon) in tensile tests. In st eel and nickel samples stress changes in the range 0-500 MPa were acco mpanied by changes in the external magnetic field in the range 0-300 A /m.