Flexible piezoelectric composite transducers
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorsLeslie E. Cross, Robert E. Newnham, Doyle P. Skinner
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Abstract
A flexible, low-density piezoelectric transducer utilizing a PZT-polymer posite that is formed with the two phases three-dimensionally interpenetrant. The ceramic PZT microstructure, which is produced by a replication process that in one embodiment reproduces the structure of a coral species, is filled with silicone rubber and thereafter its transverse connectivity is broken by a light shearing deformation to give it flexibility.
Claims14
A transducer comprising in combination
- a piezoelectric ceramic formed with a multiplicity of three-dimensionally interconnected cavities;
- an elastomer within said cavities;
- and
- an electrode attached to a pair of opposite surfaces of said ceramic.
A transducer comprising in combination
- a composite structure consisting of a piezoelectric cellular ceramic having three-dimensionally communicating cavities that are filled with silicone rubber,
- said structure being partially crushed so as to impart flexibility thereto;
- and
- an electrode attached to a pair of opposite surfaces of said structure.
A transducer comprising in combination
- a piezoelectric ceramic formed with intercommunicating cavities;
- a polymer filling said cavities and an electrode attached to a pair of opposite surfaces of said ceramic.
A composite piezoelectric transducer comprising in combination
- a ceramic structure made of PZT,
- said structure containing voids that are in communication with each other in three dimensions;
- an elastomer filling said voids;
- and
- a pair of electrodes secured to opposite surfaces of said ceramic.
The method of fabricating a piezoelectric transducer comprising the steps of
- procuring a material that contains a multiplicity of communicating cavities throughout its bulk and shaping said material to a preselected geometry;
- filling said cavities with wax and allowing said wax to harden;
- removing said material so as to leave a wax negative of its structure;
- filling the voids in said wax negative with PZT slip and polymerizing said slip,
- said wax being eliminated by said polymerizing operation;
- filling the porosity of the ceramic PZT with a polymer;
- and
- applying an electric voltage across the ceramic PZT-polymer composite for a preselected period of time.
A method of making a piezoelectric transducer that includes the steps of
- replicating the structure of a natural substance that has a multiplicity of communicating cavities,
- the reproduction resulting from said replication being made of ceramic PZT;
- filling said cavities with silicone rubber so as to form a composite substance;
- and
- applying a DC voltage across a pair of opposite surfaces of said composite for a predetermined period of time.
Dependencies are inferred from the claim text.