Analysis of Magnetostrictive Composites

The phenomenon of Joule magnetostriction is shown in Figure 30.2.

Figure 30.2 Joule magnetostriction (a) Magnetic field is proportional to current passing through the solenoid when a voltage is applied (b) Strain increases in linear fashion for lower magnetic fields.

Symmetric as well as asymmetric laminates with different stacking sequences with one of its layer embedded with Terfenol-D particulates have been taken for numerical analysis. With the application of alternating current of the form as in Equation (30.3), a compressive stress is generated in the MS layer. To balance the beam statically, there will be an equivalent and opposite tensile stress in the rest of the composite laminate. With increase in current, the stress in MS layer goes on increasing, causing increase in stresses in all other layers depending upon their placement and orientations. This results in delamination at the weakest interface where the stresses are just beyond the allowable stresses.