PMN-PT single crystal and Terfenol-D alloy magnetoelectric laminated composites for electromagnetic device applications

Magnetoelectric laminated composites of a length-magnetized magnetostrictive Tb0.3Dy0.7Fe1.92(Terfenol-D) alloy plate sandwiched between two thickness-polarized, electro-parallel- connected piezoelectric 0.7Pb (Mg1/3Nb2/3)O3-0.3PbTiO3(PMN-PT) single crystal plates were fabricated and their converse magnetoelectric properties were evaluated. An electromagnetic control device using a laminated composite as the control element and an Alnico biasing magnet, two Mn-Zn F-yokes and a Mu-metal movable plate as the magnetic circuit was developed and characterized. The distribution of the dc magnetic flux lines and magnetic inductions of the device were analyzed using a finite element method. The quasistatic and dynamic magnetic inductions of the device were measured, together with the generative forces. The results revealed that the device has linear voltagecontrolled magnetic inductions in excess of 0.6 G/V with flat responses in the measured frequency range of 0.1-40 kHz and large generative forces over 0.7 N at 160 V at the designated gaps of 1.0-1.2 mm. This coil-free device could be useful in broadband and precision magnetic flux/force control applications with negligible Joule heating losses.