Murata Manufacturing Co., Ltd.

National Institute for Materials Science

Shinichiro Kawada

Katsuhiro Horikawa

Ryoko Katayama

Yasunari Miwa

Masahiko Kimura

Shoichiro Suzuki

Hiroyuki Hayashi

Hideki Ishii

Hirozumi Ogawa

Shigetoshi Hayashi

Tadashi Okuzawa

Tetsuo Uchikoshi

Yoshio Sakka

Tohru Suzuki

Suetake Omiya

Seishiro Goto

Yusuke Nakamura

Akio Fujita

Yoshiyuki Yamakawa

Takashi Oyama

A piezoelectric actuator that includes a multilayer body, a low-potential outer electrode, and a high-potential outer electrode. The multilayer body includes multiple alternately stacked piezoelectric ceramic layers and planar electrodes. The planar electrodes include low-potential planar electrodes electrically connected to the low-potential outer electrode and high-potential planar electrodes electrically connected to the high-potential outer electrode. The planar electrode positioned most outwardly on the side of a first main surface of the multilayer body is a low-potential planar electrode. The inner surface of this low-potential planar electrode contacts the &#x2212; side of polarization in an active region, and the outer surface of this low-potential planar electrode is exposed on an outside of the multilayer body. On the side of a second main surface of the multilayer body, a high-potential planar electrode is not exposed on the outside of the multilayer body.

Piezoelectric actuator and drive method therefor

A piezoelectric ceramic that contains an alkali niobate compound as its main ingredient. The alkali niobate compound has a perovskite crystal structure represented by ABOand contains an alkali metal. There exists Sn in part of site A, and Zr in part of site B. A radial distribution function obtained from a K-edge X-ray absorption spectrum of Sn has a first peak intensity P1 at a first distance from a Sn atom and a second peak intensity P2 at a second distance from the Sn atom. The second distance is greater than the first distance, and the peak intensity ratio P1/P2 is 2.7 or less.

Piezoelectric ceramic, method for producing piezoelectric ceramic, and piezoelectric ceramic electronic component

A piezoelectric ceramic base body that has a polyhedral shape having shape anisotropy, such as a rectangular parallelepiped shape, and which has opposed faces on which external electrodes are formed. The opposed faces have first sides and second sides. Between the first side and the second side of one of the opposed faces, a width dimension of the surface in a direction orthogonal to the first side and the second side is larger than a length dimension of each of the first and the second sides. The crystal axis is {100} oriented in a direction parallel to the first and the second sides, and a degree of orientation by a Lotgering method is 0.4 or more.

Piezoelectric ceramic electronic component and method for manufacturing the same

A multilayer sintered body having alternately stacked Ni-based inner electrodes and piezoelectric ceramic layers. The piezoelectric ceramic layers contain a main ingredient of a perovskite compound containing Nb, K, Na, and Li, at least one element M1 selected from Nd and Dy, and at least one element M2 selected from Ga and Al. The element M2 content is 0.071 parts by mole or less per 1 part by mole of the Nb in a solution obtained through a dissolution process. This multilayer piezoelectric ceramic electronic component is manufactured through the cofiring of conductive films as a precursor of the inner electrodes and ceramic green sheets as a precursor of the piezoelectric ceramic layers in a reducing atmosphere in which the oxidation of Ni is inhibited.

Multilayer piezoelectric ceramic electronic component and method for manufacturing multilayer piezoelectric ceramic electronic component

Piezoelectric oriented ceramics containing a Pb(Ti, Zr)O-based compound having a high degree of orientation not lower than 0.64, which was calculated with the Lotgering method based on an X-ray diffraction pattern in a prescribed cross-section thereof, and having a sintered density not lower than 85% of a theoretical density.

Piezoelectric oriented ceramics and method of manufacturing the same

A piezoelectric ceramic includes a main constituent represented by the general formula {(1&#x2212;x) (KNaLi)(NbTa)O}&#x2212;xM2M4O}, and as accessory constituents, 2&#x3b1; mol of Na, (&#x3b1;+&#x3b2;) mole of an M4' element, and &#x3b3; mol of Mn with respect to 100 mol of the main constituent, where 0.1&#x2266;&#x3b1;&#x2266;&#x3b2;, 1&#x2266;&#x3b1;+&#x3b2;&#x2266;10, and 0&#x2266;&#x3b3;&#x2266;10, M2 is Ca, Ba, and/or Sr, the M4 element and the M4&#x2032; element are Zr, Sn, and/or Hf, 0&#x2266;x&#x2266;0.06, 0&#x2266;a&#x2266;0.9, 0&#x2266;b&#x2266;0.1, and 0&#x2266;c&#x2266;0.3. Even in the case of using Ni as the main constituent in an internal electrode material of a piezoelectric element and carrying out co-firing, favorable piezoelectric properties can be obtained without defective polarization.

Piezoelectric ceramic composition and piezoelectric ceramic electronic component

An additive that contains an emulsion binder resin substantially free of non-emulsion binder resin, such as an emulsion acrylic resin, is mixed into a ceramic raw material powder containing, as its main constituent, a perovskite-type compound to form a ceramic slurry. Then, an orientational ceramic is prepared by subjecting the slurry to a forming process while simultaneously or sequentially applying a magnetic field and drying the slurry. An orientational ceramic, even formed from a substance which has small magnetic anisotropy, such as PZT, is obtained.

Method for producing orientational ceramic, orientational ceramic, and ceramic electronic component

A piezoelectric porcelain composition includes a main ingredient represented by a general formula ((1&#x2212;x)(KNaLi) (NbTa)O&#x2212;xM2M4O) (where M2 represents Ca, Ba or Sr, M4 represents Zr, Sn or Hf, and 0.005&#x2266;x&#x2266;0.1, 0&#x2266;a&#x2266;0.9, 0&#x2266;b&#x2266;0.1, 0&#x2266;a+b&#x2266;0.9, and 0&#x2266;c&#x2266;0.3), and Mn is contained in an amount ranging from 2 to 15 mol, relative to 100 mol of the main ingredient, and the M4 is contained in an amount ranging from 0.1 to 5.0 mol, relative to 100 mol of the main ingredient. Preferably, Ni is contained in an amount ranging from 0.1 to 5.0 mol, relative to 100 mol of the main ingredient, and also preferably Yb, In and the like specific rare earth elements is contained. A ceramic layer in a ceramic base is formed of this piezoelectric porcelain composition. As a result, the degree of sintering in a reductive atmosphere is improved, and a piezoelectric porcelain composition allowing co-sintering with Ni, and a piezoelectric ceramic electronic component using the same are realized.

Piezoelectric porcelain composition, and piezoelectric ceramic electronic component

A piezoelectric ceramic base member is formed of a bar shaped bismuth layer compound, and has main electrodes on two end surfaces in an oscillation direction, with connection electrodes at side-surface central portions of the piezoelectric ceramic base member electrically connected to the main electrodes through extraction conductors interposed therebetween, respectively. The oscillation and polarization directions are set in the same direction, and the piezoelectric ceramic base member is driven at a resonant frequency or at a frequency in the vicinity thereof. The crystal c axis is preferably oriented in a direction orthogonal to the polarization direction. The resonant actuator is able to obtain a high oscillation speed as it has a large mechanical quality factor Qm, and the oscillation is not disturbed by mechanical factors.

Resonant actuator

A main component has a general formula of {(1&#x2212;x)(KNaLi)(NbTaSb)O(M1Bi)M2O} (wherein M1 is Ca, Sr or Ba, M2 is Ti, Zr or Sn, 0.005&#x2266;x&#x2266;0.5, 0&#x2266;a&#x2266;0.9, 0&#x2266;b&#x2266;0.3, 0&#x2266;a+b&#x2266;0.9, 0&#x2266;c&#x2266;0.5, 0&#x2266;d&#x2266;0.1, 0.9&#x2266;m&#x2266;1.1, and 0.9&#x2266;n&#x2266;1.1). At least one specific element selected from the group consisting of In, Sc, Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb and Lu is contained at as in sample numbers 46 to 48, 0.1 to 10 mol in total per 100 mols of the main component (preferably, 1.5 to 10 mol). This provides a piezoelectric ceramic composition and a piezoelectric ceramic electronic component that can have a desired high piezoelectric d constant in a consistent and highly efficient manner in both a very low electric field and a high electric field.

A ceramic powder contains a principal component that is a perovskite-type complex oxide represented by the formula ANbO(A is at least one selected from alkali metal elements and contains 10 mole percent or more of K) and also contains 0.0001 mole or more of an element per mole of the principal component. The element is at least one selected from the group consisting of Yb, Y, In, Nd, Eu, Gd, Dy, Sm, Ho, Er, Tb, and Lu. The ceramic powder preferably further contains at least one selected from the group consisting of Ti, Zr, and Sn. This enables that a non-deliquescent alkali niobate-based ceramic powder is produced at a high yield.

Ceramic powder and method for producing ceramic powder

A piezoelectric ceramic composition includes a primary component represented by the formula (1-x)(KNaLi)(NbTaSb)O-xM1M2O, and 0.1 to 10 moles (preferably 1.5 to 10 moles) of at least one specific element selected from the group consisting of In, Sc, Y, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu with respect to 100 moles of the primary component, wherein M1 is Ca, Sr, or Ba M2 is Ti, Zr, or Sn; and x, a, b, c, d, m, and n satisfy 0.005&#x2266;x&#x2266;0.1, 0&#x2266;a&#x2266;0.9, 0&#x2266;b&#x2266;0.3, 0&#x2266;a+b&#x2266;0.9, 0&#x2266;c&#x2266;0.5, 0&#x2266;d&#x2266;0.1, 0.9&#x2266;m&#x2266;1.1, and 0.9&#x2266;n&#x2266;1.1. Preferably, Mn, Ni, Fe, Zn, Cu, or Mg is further added. As a result, at both a very low and a high electric field, a high piezoelectric d constant can be stably obtained with a high efficiency.

Piezoelectric ceramic composition, method for manufacturing the same, and piezoelectric ceramic electronic component

A piezoelectric ceramic composition represented by the formula (1-x) (KNaLi)(NbTaSb)O-x(KNaM3) M4O, wherein M3 represents a metal element that is at least one of Yb, Y, In, Nd, Eu, Gd, Dy, Sm, Ho, Er, Tb, and Lu; M4 represents a metal element that is at least one of Ti, Zr, and Sn; and x, a, b, c, d, and m satisfy the inequalities 0.001&#x2266;x&#x2266;0.1, 0&#x2266;a&#x2266;0.9, 0&#x2266;b&#x2266;0.3, 0&#x2266;a+b&#x2266;0.9, 0&#x2266;c&#x2266;0.5, 0&#x2266;d&#x2266;0.1, and 0.7&#x2266;m&#x2266;1.3. The piezoelectric ceramic composition is not sintering resistant and has desired, sufficient piezoelectric properties as well as a sufficient firing temperature range suitable for mass production. Furthermore, the piezoelectric ceramic composition is effective in preventing insufficient polarization and effective in increasing the yield of products.

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Hikone, Japan

Shinichiro Kawada