Since the last two decades,magnetoelectric(ME)materials have been attracting considerable interest due to the potential applications,particularly in terms of magnetic field sensors,multimode energy harvesters,microelectromechanical systems,tunable microwave devices,tunable bandpass/bandstop filters,tunable phase shifters and spintronics,etc.[1,2].ME effect
In this paper,the influences of the shape of magnetic material on the magnetoelectric（ME）properties of PZT/Metglas magnetoelectric（ME）composites have been investigated.The results indicate that,with the decrease of the waist length（L w）of the dumbbell-shaped Metglas,the magnetic flux density in the center region and ME coefficients（αME）of the composites increase,while the optimal bias magnetic field H dc decreases on the contrary.In an AC magnetic field of 1 k Hz,the maximumαME（αMax）of the composite with L w=20 mm exhibits 1.3 times larger than that of the one with L w=50 mm,and the optimal H dc deceases by 15%.At the resonant frequencies of each composites,αMax is enhanced by1.3 times as L w decreases from 50 to 20 mm.The simulation made by Comsol Multiphysics and the theoretical analysis based on an equivalent magnetic circuit confirm the experimental results.
LI JunZHANG YuanLI YingweiZHU YongdanJIANG RenhuiLI Meiya
A magnetoelectric(ME) laminated composite made of one pair of piezoelectric Pb(Zr,Ti)O3(PZT) fiber layers with multiple push–pull polarization units laminated between high-permeability metglas ribbon layers with a differential configuration was proposed for vibration noise suppression. Unlike conventional metglas/PZT fiber/metglas three-layer ME laminated structures, the differential configuration has the capability to reject vibration-induced noise from the magnetic signal. The experiment results showed that the differential ME laminated composite was with up to 30 times enhancement in signal-to-noise ratio.
Designing artificial structures with heterogeneous elements and manipulating their interface coupling ways usually bring in synthetic neo-nature to functional devices.For piezoceramic devices,the deformation response refers to a variety of extensional,contractional,or shear modes of crystals,and also relies on boundary conditions from morphology design.However,to pursue fundamental torsion actuation in an integrated piezoceramic component is still a long-term tough task due to nil twist mode limited by microscopic crystal mirror symmetry.Herein,we demonstrate a design of cofired monolithic actuators to originally overcome this obstacle.The prototype device is composed of two sets of stacked actuation subunits that work on artificially reverse face shear modes,and their chiral stiffness couplings will synergistically contribute to synthetic twist outputs at a broad bandwidth.Finite element simulation reveals twist displacements are highly tunable by manipulating the geometrical dimensions.Transverse deflection measurements manifest the stable and sizeable linear actuation response to applied electric fields(around 3.7μm under 40 V at 1 Hz).Importantly,the design actually introduces a more general route to enable arbitrary modes and actuation states in integrated piezoceramic components.
Piezoelectric actuators operating in piezoelectric-induced strain/stress or electromechanical res.onanceinduced vibration or wave-motion friction drive mechanism have shown many advantagesover traditional electromagnetic mot ors,especilly,when miniaturizing into millimeter-scale size,while magnetoelectric act uators operating in magnetostrictive mechanism are capable of piezo-dlectric self-sensing and remote operation under an applied magnetic field.This paper summarizesthe recent progresses in piezoelectric ceramic and single crystal materials based actuators andmicromotors,ferromagnetic/ferroeletric laminated magnetoelectric actuat ors,including rotary,linear,planner,and spherical motion actuators,and bending motion magnetoelectric actuators.Their driving mechanisms,operation propertics,and applications are also explained.
The fabrication and properties of a novel double layered surface-mount magnetoelectric（ME） device are investigated and reported. This ME device is made up of two opposite polarized piezoelectric PZT slices bonded on the same side of a magnetostrictive material Metglas, forming a novel two PZT in-series device. ME voltage obtained from the two PZT in-series is obviously higher than that of single PZT in a magnetic field with certain value. The ME voltage coefficient（αV） of the surface-mount ME device is significantly enhanced by adjusting the thickness of Metglas： 1） At a frequency of 1 k Hz, αV of this device increases with the layer number of Metglas increased, and the maximum value of αV is about 4.25 times than the minimum; 2） At a frequency of 5 k Hz, the maximum value of αV is 458 mV /Oe, which derives from the ME device with three layers Metglas. This novel design provides an effective way to manufacture miniature and high sensitive ME devices, which makes it possible to apply ME device into integrated circuit（IC）.
LI JunZHANG YuanLI YingweiZHU YongdanJIANG RenhuiLI Meiya
