A magnetoelastic amorphous ribbon in a silicone sheath as stress sensor and self indicator of strain threshold

Abstract A magnetoelastic amorphous ribbon enveloped in silicone sheath has attenuated longitudinal magnetization intensity when is magnetized. At fixed magnetizing field, a longitudinal deformation applied to the silicone determines an ulterior decrease of magnetization intensity due to the induced friction at the interface between elastic sheath and ferromagnetic ribbon. When a threshold value of the silicone deformation is reached, an abrupt increase of magnetization occurs, corresponding to the exceeding of the maximum internal friction by the induced deformation. This effect can be used to design strain, stress, and/or magnetic field threshold indicators, which can be calibrated for different levels.