A ceramic member includes a matrix phase of a perovskite compound including La, Ca, and Mn, and a heterophase including Mn and O as main components, wherein crystal grains of the perovskite compound have an average grain size of about 2.5 μm or more and about 6.4 μm or less.

Provided is a multilayer ceramic capacitor having dielectric layers and internal electrode layers laminated alternately on one another. Each internal electrode layer comprises a common ceramic material containing 3 to 25% by weight of rare earth elements, and through the rare earth elements, high dielectric layers are formed on the interfaces between the dielectric layers and the internal electrode layers.

A manufacturing method of a dielectric ceramic composition includes attaching a reactive functional group to a surface of a base material powder particle of a perovskite structure.

A zirconia sintered body that includes a transparent zirconia portion and an opaque zirconia portion has a biaxial bending strength of 300 MPa or more. In addition, the opaque zirconia portion is configured by an opaque zirconia sintered body that is any one of a dark-colored zirconia sintered body, a medium-light-colored zirconia sintered body, and a light-colored zirconia sintered body.

A temperature sensor element includes: an element main body including a heat sensitive body including a thermistor sintered body of which the electrical characteristics change with temperature, and a pair of lead wires that is connected to the heat sensitive body through electrodes; and a protective layer that protects the heat sensitive body. The protective layer has an inner protective layer covering the heat sensitive body and an outer protective layer covering the outer side of the inner protective layer. The inner protective layer is formed of an aggregate of particles that are chemically stable with respect to the thermistor sintered body and made of non-metal.

A ceramic member includes a perovskite compound including La, Ca, Mn, and Ti as main components, wherein the amount of Ti is about 5 parts by mole or more and about 20 parts by mole or less, the amount of Ca is about 10 parts by mole or more and about 27 parts by mole or less, and the total amount of La and Ca is about 85 parts by mole or more and about 97 parts by mole or less based on the total amount of Mn and Ti of 100 parts by mole.

A piezoelectric material includes: an oxide containing Na, Ba, Nb, Ti, and Mn, in which the oxide has a perovskite-type structure, a total amount of metal elements other than Na, Ba, Nb, Ti, and Mn contained in the piezoelectric material is 0.5 mol % or less with respect to a total amount of Na, Ba, Nb, Ti, and Mn, a molar ratio x of Ti to a total molar amount of Nb and Ti is 0.05≤x≤0.12, a molar ratio y of Na to Nb is 0.93≤y≤0.98, a molar ratio z of Ba to Ti is 1.09≤z≤1.60, a molar ratio m of Mn to the total molar amount of Nb and Ti is 0.0006≤m≤0.0030, and 1.07≤y×z≤1.50 is satisfied.

Provided are a piezoelectric ceramics which does not contain lead, has small temperature dependence of a piezoelectric constant within an operating temperature range, and has high density, a high mechanical quality factor, a satisfactory piezoelectric constant, and a small surface roughness, and a method of manufacturing the piezoelectric ceramics. The method of manufacturing a piezoelectric ceramics is characterized by including: sintering a compact containing a raw material at 1,000° C. or more to obtain a sintered compact; abrading the sintered compact; and annealing the abraded sintered compact at a temperature of 800° C. or more and less than 1,000° C.

Ferrite powder of the present invention is ferrite powder detectable with a metal detector, comprising: soft ferrite particles containing Mn of 3.5 mass % or more and 20.0 mass % or less and Fe of 50.0 mass % or more and 70.0 mass % or less. It is preferable that a volume average particle diameter of the particles constituting the ferrite powder is 0.1 μm or more and 100 μm or less. It is preferable that magnetization by a VSM measurement when magnetic field of 5 K.Math.1000/4πA/m is applied is 85 A.Math.m.sup.2/kg or more and 98 A.Math.m.sup.2/kg or less.

A thermistor sintered body stably provides a desired B constant even if a composition deviation of an additive element has occurred. The thermistor sintered body includes a Y.sub.2O.sub.3 phase and a Y(Cr, Mn)O.sub.3 phase, wherein a chemical composition of Cr, Mn, Ca, and Y excluding oxygen is Cr: 3 to 12 mol %, Mn: 5 to 15 mol %, Ca: 1 to 8 mol %, and Sr: 1 to 25 mol %, with the balance being unavoidable impurities and Y. In the thermistor sintered body, Ca and Sr may be dissolved in the Y(Cr, Mn)O.sub.3 phase.