743 results about "Piezoelectric composite" patented technology

A method for producing a piezoelectric composite substrate having a single-crystal thin film of a piezoelectric material includes an ion-implantation step and a separation step. In the ion-implantation step, He+ ions are implanted into the single-crystal base made of the piezoelectric material to form localized microcavities in a separation layer located inside the single-crystal base and apart from a surface of the single-crystal base. In the separation step, the microcavities formed in the ion-implantation step are subjected to thermal stress to divide the separation layer of the piezoelectric single-crystal base, thereby detaching the single-crystal thin film.

Provided is a method for manufacturing multiple devices on a single piezoelectric composite substrate. The piezoelectric composite substrate is significantly larger than a size required for a single device, thus multiple sensors can be simultaneously fabricated from the same piezoelectric composite substrate.

The invention discloses a multimode broadband circular array transducer, which comprises a piezoelectric composite material cambered base array, a decoupling material, a back lining, a shell, a matching layer, a water sealing joint and a cable, wherein the piezoelectric composite material cambered base array is formed by uniformly arranging a plurality of piezoelectric composite material base elements; the decoupling material is filled between the piezoelectric composite material base elements, so that a circular sensitive element is formed; the back lining is tightly attached to the inner side of the circular sensitive element; the shell supports and encircles the sensitive element and the back lining; the matching layer is poured on the outer side of the sensitive element; electrodes are arranged on the upper surfaces and the lower surfaces of the piezoelectric composite material base elements, so that positive electrodes and negative electrodes are led out by wires; wire holes are formed in the back lining, so that the wires pass through the wire holes; a wire outlet is formed on the shell; the water sealing joint seals the wire outlet; and the wires are connected with the cable in the water sealing joint. The transducer has the characteristics of high frequency, high sensitivity, broadband and large directive opening angle.

The invention introduces an epoxy resin-based piezoelectric and composite damping material and a preparation method thereof, which comprises the following materials by weight portion: 100 portions of epoxy resin, 30 portions to 220 portions of piezoelectric ceramic powder, 0.5 portion to 5 portions of graphitized carbon black and 30 portions to 120 portions of curing agent. After being mixed, dispersed and added with the curing agent to be evenly blended and then poured, cured and shaped, the piezoelectric and composite material can be polarized in an HVDC oil-bath electric field and has good damping property (tan Delta is not less than 0.3) in a wide-temperature range (10 to 100 DEG C) and can also be applied in projects as free damping material as well as in an intelligent vibration and noise reduction system. In addition, the piezoelectric and composite material can be made into damping paint, putty, slurry and potting adhesive and poured into various section materials to be used in vibration and noise reduction projects in the fields such as vehicles, industrial machinery, civil construction, household appliances, precision instruments, military equipment, etc.

Disclosed herein is a piezoelectric composite device including: a feeding electrode; a common electrode; a signal detecting electrode; a first piezoelectric element joined between the feeding electrode and the common electrode; and a second piezoelectric element joined between the common electrode and the signal detecting electrode; a predetermined voltage being supplied between the feeding electrode and the common electrode; and a force detection signal based on an external force being extracted from the detecting electrode.

The present invention relates to a spring leaf-type bistable electromagnetic piezoelectric composite energy collecting device, including a static mechanism and a movable mechanism. The static mechanism comprises a housing, and the housing is internally provided with a bearing bearer, a fixed magnet, an upper coil and a lower coil. The movable mechanism comprises a pendulum frame, a spring piece and a vibration magnet and a spring piece is a V-shaped or U-shaped sheet. In the natural state, the upper and lower ends of the spring piece are in contact with the inner top wall and the inner bottom wall of the housing respectively. The vibration magnet and the fixed magnet are magnetized in the axial direction and repel each other. Under the action of external vibration excitation, the swinging of the pendulum frame drives the rotation of a rotating shaft, and then the spring piece and a piezoelectric element are deformed and the electric charge is generated. The electric energy is outputted through an electrode terminal lead. When the vibration magnet on the pendulum frame swings up and down, the magnetic field around the magnet also moves, the coil in the magnetic field cuts the magnetic induction lines and generates induced current, and the current is output through the lead.

The invention discloses a shearing-type piezoelectric composite material. The outermost two layers of the composite material structure are flexible insulated thin films, the middle layer is a piezoelectric phase / epoxy resin composite layer, and interdigital electrodes are arranged between the middle layer and the flexible insulated thin films; the positive electrode finger parts and the negative electrode finger parts of the interdigital electrodes are arranged alternatively at equal distances, and the upper interdigital electrode and the lower interdigital electrode are in mirror symmetry and aligned; the finger parts of the interdigital electrodes are parallel to the piezoelectric phase of the piezoelectric phase / epoxy resin composite layer, and the electrode finger parts are located on the upper surface and the lower surface of the edge of the piezoelectric phase and epoxy resin joining surface; and the piezoelectric phase polarization direction is a direction vertical with the composite layer plane. The sheet piezoelectric composite material provided by the invention is thin in thickness, compact in structure, can fit a curved surface structure, can realize a certain degree of flexible deformation, and can be made into a driver, a sensor and the like.

The invention relates to an electromagnet-friction piezoelectric composite energy harvester and belongs to the technical fields of micro-electro-mechanical systems and micro energy. Permanent magnets are placed on the two sides in a shell of the harvester, a rotary shaft is connected with the shell through a bearing, a cantilever beam in an internal dent shape is fixedly connected to the rotary shaft, and the two ends of the cantilever beam are fixedly connected with hemispherical mass blocks respectively. Piezoelectric ceramics coated with a buffer layer are installed in the shell, a coil is wound around the cantilever beam, a second friction layer is attached to the exterior of the coil, and a first friction layer, a flexible piezoelectric material and an insulated filling layer are sequentially arranged on the corresponding positions between the second friction layer and the shell. Harvested energy is output through external lines of a first electrode layer and a second electrode layer, the first electrode layer is connected with the flexible piezoelectric material and the first friction layer, and the second electrode layer is located on the upper portion of the rotary shaft, and connected with the coil and the second friction layer through wires. The electromagnet-friction piezoelectric composite energy harvester has the advantages that vibrational energy is converted into electric energy, the output energy is amplified in a summed mode, and the energy conversion efficiency of the harvester is further improved.

An example flexoelectric-piezoelectric apparatus provides an electrical response to an applied force, and / or an actuation in response to an applied electric field, that originates from the flexoelectric properties of a component. For example, shaped forms within the apparatus may be configured to yield a stress gradient on application of the force, and the stress gradient induces the flexoelectric signal. A flexoelectric-piezoelectric apparatus can be substituted for a conventional piezoelectric apparatus, but does not require the use of a piezoelectric material. Instead, the response of the apparatus is due to the generation of stress gradients and / or field gradients.

The invention provides a piezoelectric ceramic, polyvinylidene fluoride (PVDF) and pressure-sensitive material three-phase composite material with high piezoelectric property. The pressure-sensitive material is added to a piezoelectric ceramic / PVDF piezoelectric composite material as an intermediate layer, so as to play a bridging role; the interfacial bonding properties of the piezoelectric ceramic and the PVDF are improved; coupling between the piezoelectric ceramic and the PVDF is increased; electron migration between ceramic particles is promoted; and the polarization voltage of a ceramic phase is improved. In addition, due to the nonlinear current-voltage characteristics of the pressure-sensitive material, when the pressure-sensitive material is added to the piezoelectric ceramic and PVDF composite material, the polarization-resistant voltage of the piezoelectric composite material is improved; and the overall piezoelectric property of the composite material is improved. Therefore, the piezoelectric composite material is simple in process, and low in cost; the piezoelectric composite film with excellent overall performance and large size can be prepared; and the piezoelectric composite material is expected to be applied to a piezoelectric touchpad, thus industrialized production is achieved.

Provided are a method of manufacturing a flexible piezoelectric energy harvesting device using a piezoelectric composite, and a flexible piezoelectric energy harvesting device manufactured by the same. The method of manufacturing the flexible piezoelectric energy harvesting device includes: forming a first electrode layer on a first flexible substrate; spin-coating a piezoelectric composite layer on the first electrode layer, wherein the piezoelectric composite layer is produced by mixing piezoelectric powder with polymer; performing heat treatment on the piezoelectric composite layer to harden the piezoelectric composite layer; and bonding a second flexible substrate with a second electrode layer on the hardened piezoelectric composite layer. Therefore, it is possible to simplify a manufacturing process and manufacture a high-performance flexible piezoelectric energy harvesting device having various sizes and patterns.

A method and apparatus attains high voltage gain by using a composite structure of an elastic section of piezoelectric layers bonded between magnetic and electric sections of magnetostrictive layers, with a harmonic magnetic field being applied along the layers at a mechanical resonance frequency of the composite structure, through coils around the laminate carrying current, such as to produce a continuity of both magnetic and electric flux lines, and achieving a high voltage output.