The present invention provides a lead-free piezoelectric material having a high piezoelectric constant and a high mechanical quality factor in a wide operating temperature range. The piezoelectric material includes a perovskite-type metal oxide represented by Formula (1):
(Ba.sub.1-xCa.sub.x).sub.a(Ti.sub.1-yZr.sub.y)O.sub.3 (1.00≦a≦1.01, 0.125≦x<0.155, and 0.041≦y≦0.074)
as a main component. The metal oxide contains Mn in a content of 0.12 parts by weight or more and 0.40 parts by weight or less based on 100 parts by weight of the metal oxide on a metal basis.

An armor component including a body having a first portion including calcium boride compounds include non-stoichiometric calcium boride (CaB.sub.x) and stoichiometric calcium boride (CaB.sub.6) and having a density of at least about 80% theoretical density. In one aspect, the first portion can include a first phase comprising silicon carbide (SiC) and a second phase comprising calcium boride (CaB.sub.6). In another aspect, the first portion can further include a third phase comprising boron carbide (B.sub.4C).

Disclosed are embodiments of synthetic garnet materials for use in radiofrequency applications. In some embodiments, increased amounts of bismuth can be added into specific sites in the crystal structure of the synthetic garnet in order to boost certain properties, such as the dielectric constant and magnetization. Accordingly, embodiments of the disclosed materials can be used in high frequency applications, such as in base station antennas.

A manganese oxide contains M1, optionally M2, Mn and O. M1 is selected from the group consisting of In, Sc, Y, Dy, Ho, Er, Tm, Yb and Lu. M2 is different from M1, and M2 is selected from the group consisting of Bi, In, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. These ceramic materials are hexagonal in structure, and provide superior materials for gas separation and oxygen storage.

Provided is a lead-free piezoelectric material having satisfactory piezoelectric constant and mechanical quality factor in a device driving temperature range (−30° C. to 50° C.) The piezoelectric material includes a main component containing a perovskite-type metal oxide represented by Formula 1, a first auxiliary component composed of Mn, and a second auxiliary component composed of Bi or Bi and Li. The content of Mn is 0.040 parts by weight or more and 0.500 parts by weight or less based on 100 parts by weight of the metal oxide on a metal basis. The content of Bi is 0.042 parts by weight or more and 0.850 parts by weight or less and the content of Li is 0.028 parts by weight or less (including 0 parts by weight) based on 100 parts by weight of the metal oxide on a metal basis. (Ba.sub.1-xCa.sub.x).sub.a(Ti.sub.1-yZr.sub.y)O.sub.3 . . . (1), wherein, 0.030≦x<0.090, 0.030≦y≦0.080, and 0.9860≦a≦1.0200.

A W.sub.18O.sub.49 peak is confirmed by X-ray diffraction analysis of a sputtering surface and a cross section orthogonal to the sputtering surface, a ratio I.sub.S(103)/I.sub.S(010) of a diffraction intensity I.sub.S(103) of a (103) plane to a diffraction intensity I.sub.S(010) of a (010) plane of W.sub.18O.sub.49 of the sputtering surface is 0.38 or less, a ratio I.sub.C(103)/I.sub.C(010) of a diffraction intensity I.sub.C(103) of the (103) plane to a diffraction intensity I.sub.C(010) of the (010) plane of W.sub.18O.sub.49 of the cross section is 0.55 or more, and an area ratio of W.sub.18O.sub.49 phase of a surface parallel to the sputtering surface is 37% or more.

Provided is a dielectric composition exhibiting a high strength and a high specific dielectric constant. The dielectric composition contains composite oxide particles having a composition formula represented by (Sr.sub.xBa.sub.1-x).sub.yNb.sub.2O.sub.5+y and an Al-based segregation phase. The Al segregation phase has niobium, aluminum, and oxygen.

(i) a step of disposing a powder that includes an absorber absorbing light of a wavelength included in a laser beam to be irradiated and silicon dioxide as a main component; (ii) a step of sintering or melting and solidifying the powder by irradiating the powder with a laser beam; and (iii) a step of heat-treating a shaped object formed by repeating the steps (i) and (ii) at 1470° C. or more and less than 1730° C.

A ceramic body being configured of mainly BaTiO.sub.3-based crystalline particles in which a part of Ba is substituted with at least one rare earth element, wherein the ceramic body contains Ba.sub.6Ti.sub.17O.sub.40 crystalline particles of from 1.0 to 10.0% by mass.

A module having a power semiconductor device and a ceramic capacitor which is configured for cooling the power semiconductor device.