J. Kaleta et al., MAGNETORESISTORS AS A TOOL FOR INVESTIGATING THE MECHANICAL-PROPERTIES OF FERROMAGNETIC MATERIALS, Journal of magnetism and magnetic materials, 160, 1996, pp. 199-200
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.