Multifunctional Boron Nitride nanotube-Boron Nitride (BN—BN) nanocomposites for energy transducers, thermal conductors, anti-penetrator/wear resistance coatings, and radiation hardened materials for harsh environments. An all boron-nitride structured BN—BN composite is synthesized. A boron nitride containing precursor is synthesized, then mixed with boron nitride nanotubes (BNNTs) to produce a composite solution which is used to make green bodies of different forms including, for example, fibers, mats, films, and plates. The green bodies are pyrolized to facilitate transformation into BN—BN composite ceramics. The pyrolysis temperature, pressure, atmosphere and time are controlled to produce a desired BN crystalline structure. The wholly BN structured materials exhibit excellent thermal stability, high thermal conductivity, piezoelectricity as well as enhanced toughness, hardness, and radiation shielding properties. By substituting with other elements into the original structure of the nanotubes and/or matrix, new nanocomposites (i.e., BCN, BCSiN ceramics) which possess excellent hardness, tailored photonic bandgap and photoluminescence, result.

Provided are a barium titanate-based piezoelectric ceramics having satisfactory piezoelectric performance and a satisfactory mechanical quality factor (Q.sub.m), and a piezoelectric element using the same. Specifically provided are a piezoelectric ceramics, including: crystal particles; and a grain boundary between the crystal particles, in which the crystal particles each include barium titanate having a perovskite-type structure and manganese at 0.04% by mass or more and 0.20% by mass or less in terms of a metal with respect to the barium titanate, and the grain boundary includes at least one compound selected from the group consisting of Ba.sub.4Ti.sub.12O.sub.27 and Ba.sub.6Ti.sub.17O.sub.40, and a piezoelectric element using the same.

A lead-free piezoelectric ceramic composition mainly includes a first crystal phase (KNN phase) and a second crystal phase (NTK phase). In the first crystal phase (KNN phase), a plurality of crystal grains formed of an alkali niobate/tantalate perovskite oxide having piezoelectric characteristics is bound to each other in a deposited state. The second crystal phase (NTK phase) is formed of a compound containing titanium (Ti) and fills spaces between the crystal grains in the first crystal phase.

A piezoelectric element having an improved piezoelectric constant is provided, and a liquid discharge head, an ultrasonic motor, and a dust removing device, each of which uses the above piezoelectric element, are also provided. A piezoelectric element at least includes a pair of electrodes and a piezoelectric material provided in contact with the pair of electrodes, the piezoelectric material is formed of an aggregate of crystal grains containing barium titanate as a primary component, and among the crystal grains of the aggregate, crystal grains at least in contact with the electrodes have dislocation layers in the grains. A liquid discharge head, an ultrasonic motor, and a dust removing device each use the above piezoelectric element.

A piezoelectric ceramic has a primary phase constituted by ceramic grains of perovskite crystal structure containing Pb, Nb, Zn, Ti, and Zr, and a secondary phase constituted by ZnO grains present sporadically in the primary phase. The piezoelectric ceramic of high kr and high specific dielectric constant can be sintered at low temperature and exhibit minimal characteristics variations.

The invention relates to a ceramic material, comprising lead zirconate titanate, which additionally contains K and optionally Cu. The ceramic material can be used in an electroceramic component, for example a piezoelectric actuator. The invention also relates to methods for producing the ceramic material and the electronic component.

A piezoelectric ceramic electronic component that includes a piezoelectric ceramic body including at least one piezoelectric ceramic layer; and a plurality of electrodes on a surface or inside of the piezoelectric ceramic body and arranged so that the at least one piezoelectric ceramic layer is sandwiched between adjacent electrodes of the plurality of electrodes. The at least one piezoelectric ceramic layer is a ceramic sintered body containing a potassium sodium niobate-based compound and Mn. When the at least one piezoelectric ceramic layer sandwiched between the adjacent electrodes is divided into three equal parts in a thickness direction to sequentially define a first region, a second region, and a third region between the adjacent electrodes, a second Mn concentration in the second region is higher than a first Mn concentration in the first region and a third Mn concentration in the third region.

The present disclosure relates to a method for obtaining lead-free piezoelectric materials, including: Step S100, adjusting the T/O phase boundary of a first lead-free piezoelectric material: for the first lead-free piezoelectric material, adjusting the T/O phase boundary between the tetragonal phase T and the orthorhombic phase O to be near the room temperature by doping; Step S200, further adjusting the C/T phase boundary and the O/R phase boundary: further adjusting the C/T phase boundary between the cubic paraelectric phase C and the tetragonal phase T, and the O/R phase boundary between the orthorhombic phase O and the rhombohedral phase R by doping, so as to enable the C/T phase boundary and the O/R phase boundary to approach the T/O phase boundary; and Step S300, obtaining second lead-free piezoelectric materials: obtaining multiple second lead-free piezoelectric materials with different piezoelectric constants d.sub.33 and different Curie temperatures T.sub.C in the process.

Provided is a piezoelectric material filler including alkali niobate compound particles having a ratio (K/(Na+K)) of the number of moles of potassium to the total number of moles of sodium and potassium of 0.460 to 0.495 in terms of atoms and a ratio ((Li+Na+K)/Nb) of the total number of moles of alkali metal elements to the number of moles of niobium of 0.995 to 1.005 in terms of atoms. The present invention can provide a piezoelectric material filler having excellent piezoelectric properties, and a composite piezoelectric material including the piezoelectric material filler and a polymer matrix.

The ceramic material element includes a main phase of orthorhombic perovskite-structure and a secondary phase due to a heat treatment within 700° C. to 850° C. for a first period followed by a second period within 1140° C. to 1170° C., from a mixture of materials A1, A2, A3, A4 and A5 excluding lead, the materials A1, A2, A3, A4 and A5 having molar ratios R1, R2, R3, R4 and R5, respectively, where the material A1 comprises potassium, the material A2 comprises sodium, the material A3 comprises barium, the material A4 comprises niobium, and the material A5 comprises nickel, and the molar ratio R1 is in a range 0.29-0.32, the molar ratio R2 is in a range 0.20-0.23, the molecular ratio R3 is in a range 0.01-0.02, the molar ratio R4 is in a range 0.54-0.55, and the molar ratio R5 is in a range 0.006-0.011, while a relative ratio of R1/R2 is in the range 1.24-1.52, and a relative ratio of R4/R2 is in the range 2.32-2.62. The ceramic material element converts optical radiation energy and mechanical vibration energy into electric energy.