A piezoelectric composite transducer and method for making same are disclosed. A block of piezoelectric material has a common base and a plurality of uniform-length rods extending from the common base in a parallel spaced-apart fashion to define an array. A first surface region is defined at outboard ends of the rods and a side region is defined about the periphery of the array. Electric conductors extend through the side region, are routed parallel to the first surface region, and are then led substantially parallel to the rods to the first surface region. Spaces between the rods are filled up to the first surface region with a viscoelastic material. The common base of the block is then removed such that a second surface region parallel and opposite to the first surface region is defined. Electrodes are deposited at the first surface region to be in contact with the rods and in electrical contact with the electric conductors. A ground electrode is deposited at the second surface region to be in contact with the rods. The resulting piezoelectric composite transducer can be heated and shaped to conform to complex curves.
A modular sub-array assembly of a composite towed array includes a multi-chamber support structure with plural discrete chambers, an acoustically absorptive hub formed at a central axis of the multi-chamber support structure, and a sensor element in each of the chambers of the multi-chamber support structure. The multi-chamber support structure is an integrally formed viscoelastic cylindrical housing with an array of radially oriented chambers. Each sensor element is secured within the selected chamber of the multi-chamber support structure and to an outer radial surface of the acoustically absorptive hub by a structural adhesive. Plural sub-array modules may be assembled together to form a single towed array.
A method for fabricating a piezoelectric macro-fiber composite actuator comprises providing a piezoelectric material that has two sides and attaching one side upon an adhesive backing sheet. The method further comprises slicing the piezoelectric material to provide a plurality of piezoelectric fibers in juxtaposition. A conductive film is then adhesively bonded to the other side of the piezoelectric material, and the adhesive backing sheet is removed. The conductive film has first and second conductive patterns formed thereon which are electrically isolated from one another and in electrical contact with the piezoelectric material. The first and second conductive patterns of the conductive film each have a plurality of electrodes to form a pattern of interdigitated electrodes. A second film is then bonded to the other side of the piezoelectric material. The second film may have a pair of conductive patterns similar to the conductive patterns of the first film.
An ultrasonic probe is characterized in that a piezoelectric member 111 formed of solution-based single-crystal containing at least plumbum titanate is sandwiched between resin layers 113 and 115 having smaller acoustic impedance than the piezoelectric member and having conductivity, so processing errors are prevented from occurring during cutting and the resin layers can be used as acoustic layers or electrodes.
A method for fabricating a piezoelectric macro-fiber composite actuator comprises making a piezoelectric fiber sheet by providing a plurality of wafers of piezoelectric material, bonding the wafers together with an adhesive material to form a stack of alternating layers of piezoelectric material and adhesive material, and cutting through the stack in a direction substantially parallel to the thickness of the stack and across the alternating layers of piezoelectric material and adhesive material to provide at least one piezoelectric fiber sheet having two sides comprising a plurality of piezoelectric fibers in juxtaposition to the adhesive material. The method further comprises bonding two electrically conductive films to the two sides of the piezoelectric fiber sheet. At least one conductive film has first and second conductive patterns formed thereon which are electrically isolated from one another and in electrical contact with the piezoelectric fiber sheet.
