Method and Apparatus for High-Permeability Magnetostrictive/Piezo-Fiber Laminates Having Colossal, Near-Ideal Magnetoelectricity
View Patent ↗An ME composite laminate of at least one (1-3) piezo-fiber layer coupled with high-permeability alloy magnetostrictive layers, optionally formed of FeBSiC or equivalent. The composite laminate alternates the (1-3) piezo-fiber and high-permeability alloy magnetostrictive layers in a stacked manner. Optionally, the magnetization direction of the high-permeability alloy magnetostrictive layers and polarization direction of the piezo-fiber layer are an (L-L) arrangement. Optionally, thin film polymer layers are between the (1-3) piezo-fiber layer and high-permeability alloy magnetostrictive layers. Optionally, piezo-electric fibers within the (1-3) piezo-fiber layer are poled by inter-digitated electrodes supported by the thin film polymer, arranged as alternating symmetric longitudinally-poled “push-pull” units.
1. A high-permeability (L-L) configuration magnetostrictive/piezo-electric composite laminate comprising:
a (1-3) piezo-fiber layer having piezo-electric fibers extending in a longitudinal direction;
first and second high-permeability magnetostrictive alloy layers, the (1-3) piezo-fiber layer being laminated between the first and second high-permeability magnetostrictive alloy layers in an (L-L) configuration, wherein the magnetization axis of the first and second magnetostrictive alloy layers extends in the same longitudinal direction as the piezo-electric fibers forming the (1-3) piezo-fiber layer; and
first and second thin polymer insulating layers, each with inter-digitated (ID) electrodes, placed between respective first and second high-permeability magnetostrictive alloy layers and the (1-3) piezo-fiber layer.
2. The high-permeability (L-L) configuration magnetostrictive/piezo-electric composite laminate of claim 1 , wherein the high permeability magnetostrictive layer comprises FeBSiC.
3. The high-permeability (L-L) configuration magnetostrictive/piezo-electric composite of laminate of claim 1 , wherein the (1-3) piezo-fiber layer comprises a plurality of PZT ceramic piezo-electric fibers, bound in a resin binder, extending in the longitudinal direction.
4. The high-permeability (L-L) configuration magnetostrictive/piezo-electric composite laminate of claim 1 , wherein the plurality of electrodes includes a plurality of longitudinally-poled “push-pull” units, arranged in an alternating symmetric arranged with a given spacing between adjacent like-polarity electrodes in said longitudinal direction.