A piezoelectric element includes a piezoelectric body including a piezoelectric material, and a first electrode and a second electrode provided on the piezoelectric body. The piezoelectric body includes a base and a plurality of drivers. The base includes a first main surface and a second main surface opposing each other. The plurality of drivers is arranged on the first main surface in such a way as to be separate from each other. Each of the plurality of drivers includes a third main surface contacting the first main surface and a fourth main surface opposing the third main surface. The base includes a plurality of first regions in which the plurality of drivers is provided and a second region provided between the first regions adjacent to each other. The base is curved.

Provided is an electric field-vibration generating transducer having a piezoelectric material of a high degree of displacement, and a manufacturing method thereof. The electric field-vibration generating transducer lowers the cost of production through miniaturization simultaneously with realizing excellent generating characteristics of the electric field-vibration generating transducer based on high efficiency and low voltage driving because the piezoelectric material of the high degree of displacement (high strain piezoelectrics) having a high piezoelectric constant (d.sub.33=1,000 to 6,000 pC/N), a high dielectric constant (K.sub.3.sup.T=6,000 to 15,000) as well as a low dielectric loss (tan δ<2%) is applied thereto, so the electric field-vibration generating transducer may accelerate the movement of a material, a chemical action, and a biological reaction, and may be applied to a medical device for the purpose of treatment for tumors aimed at human bodies and animals.

Provided is a polymer-based piezoelectric composite material film which has high conversion efficiency and is capable of reproducing a sound with a sufficient volume. The polymer-based piezoelectric composite material film is a film including a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material, and two electrode layers which are laminated on both surfaces of the polymer-based piezoelectric composite material, in which a coefficient of variation of intensity ratio α.sub.1 of (002) plane peak intensity and (200) plane peak intensity derived from the piezoelectric particles=(002) plane peak intensity/((002) plane peak intensity+(200) plane peak intensity) in a case where the polymer-based piezoelectric composite material is evaluated by an X-ray diffraction method is less than 0.3.

A lead-free piezoelectric ceramic sensor material and a preparation method thereof, and relates to the technical field of piezoelectric ceramic processing. The main raw materials of the lead-free piezoelectric ceramic sensor material disclosed in the present disclosure are a barium carbonate, a calcium carbonate, a zirconia, a titanium dioxide, a strontium carbonate, an oxidation bait, a bismuth oxide, a composite binder and a dispersant agent. The preparation method is prepared through the steps of preparing ingredients, ball milling, granulating and tableting, debinding, and sintering, and the lead-free piezoelectric ceramic sensor material can be made into a lead-free piezoelectric sensor through applying an electrode and electrode polarizing. The present disclosure has an excellent compactness and a good chemical stability. And the piezoelectric sensor made of the lead-free piezoelectric ceramic sensor material has a high sensitivity, a strong working stability, an excellent piezoelectric and has a high Curie temperature.

A polymer composite exhibiting piezoelectric properties can be formed for flexible and/or thin film applications, in which the polymer composite includes a polymer matrix and a piezoelectric ceramic filler embedded in the polymer matrix. The polymer matrix may include at least two polymers: a first polymer and a second polymer. The first polymer may be a fluorinated polymer, and the second polymer may be compatible with the first polymer and have a dielectric constant of less than approximately 20. The piezoelectric ceramic filler can be lithium doped potassium sodium niobite (KNLN), and be approximately 40-70% by volume of the polymer composite. The remaining 30-60% by volume may be the polymer matrix, which may itself be approximately 5-20% by weight second polymer and 80-95% fluorinated polymer.

A polymer composite exhibiting piezoelectric properties can be formed for flexible and/or thin film applications, in which the polymer composite includes a polymer matrix and a piezoelectric ceramic filler embedded in the polymer matrix. The polymer matrix may include at least two polymers: a first polymer and a second polymer. The first polymer may be a fluorinated polymer, and the second polymer may be compatible with the first polymer and have a dielectric constant of less than approximately 20. The piezoelectric ceramic filler can be lithium doped potassium sodium niobite (KNLN), and be approximately 40-70% by volume of the polymer composite. The remaining 30-60% by volume may be the polymer matrix, which may itself be approximately 5-20% by weight second polymer and 80-95% fluorinated polymer.

A piezoelectric transformer and a method for producing a piezoelectric transformer are disclosed. In an embodiment, the method includes manufacturing a main body having an input region having electrodes and a first piezoelectric material being alternately stacked one on top of the other. An output region includes a second piezoelectric material. The first piezoelectric material is polarized and a removable contact is fitted to an output-side end side of the main body, which end side faces away from the input region. A first electrical potential is applied to the removable contact for polarizing the second piezoelectric material.

To provide a piezoelectric film that is less likely to be electrified and that can be safely handled. A multilayered film according to an embodiment of the present invention including: a piezoelectric film containing polyvinylidene fluoride; and a protective film including an antistatic layer, the piezoelectric film and the protective film being bonded.

A method for depolarization suppression of in rhombohedral relaxor-based ferroelectric single crystal. The purpose of the present invention is to address the problem that the rhombohedral relaxor-based ferroelectric single crystals would depolarize when driven to sufficiently electric field due to their low coercive field. In the present invention, the crystal cut, poling direction and compressive stress application direction of the crystal is selected based on the domain structure and anisotropic nature of the crystal such that the spontaneous direction(s) of the crystal would rotate towards the poling direction in response to the applied compressive stress. Through application of appropriate compressive stress, the magnitude of depolarization field of the rhombohedral relaxor-based ferroelectric single crystals can be effectively increased.

An object is to provide a fluorine-containing polymer film. The object can be achieved by a fluorine-containing polymer film having a thermal shrinkage of 0.4% or less after being heated at 90° C. for 1 hour, and having a relative permittivity of 3 to 50 at 25° C. at 1000 Hz, or a fluorine-containing polymer film having a crystallinity of 50% or more and an elongation at break of 400% or more.