A preform for making a component of a braking system having a fibre-reinforced ceramic composite material, obtained by forming and subsequent pyrolysis of a pre-preg is described. Also described is a component of a braking system made wholly or in part from the preform, and a method for making a preform in a fibre-reinforced ceramic composite material.

A paramagnetic garnet-type transparent ceramic characterized by being a sintered body of a terbium-containing composite oxide represented by formula (1) in which the linear transmittance at a wavelength of 1,064 nm at an optical path length of 15 mm is 83% or higher.
(Tb.sub.1-x-ySc.sub.xCe.sub.y).sub.3(Al.sub.1-zSc.sub.z).sub.5O.sub.12  (1)
(In the formula, 0<x<0.08, 0≤y≤0.01, 0.004<z<0.16.)

A solid composition according to the present disclosure is a solid composition to be used for forming a functional ceramic having a crystal phase, and contains an oxide constituted by a crystal phase different from the crystal phase of the functional ceramic at normal temperature and normal pressure, and an oxoacid compound. The oxoacid compound preferably contains at least one of a nitrate ion and a sulfate ion as an oxoanion. Further, the oxide preferably has a crystal grain size of 10 nm or more and 200 nm or less.

The invention relates to a pre-impregnated fibre-reinforced composite material in laminar form, obtained impregnating a fibrous mass with a polymeric binder composition and intended to be subjected to successive forming and pyrolysis operations to produce a fibre-reinforced composite ceramic material. The polymeric binder composition is based on one or more resins chosen from the group consisting of siloxane resins and silsesquioxane resins, and can optionally comprise one or more organic resins. The polymeric binder composition is a liquid with viscosity between 55000 and 10000 mPas at temperatures between 50° C. and 70° C. The polymeric binder composition forms a polymeric binding matrix, not cross-linked or only partially cross-linked that fills the interstices of the fibrous mass. The invention also relates to a method for making said pre-impregnated fibre-reinforced composite material in laminar form. The invention further relates to a fibre-reinforced composite ceramic material, obtained by forming and subsequent pyrolysis of a pre-impregnated fibre-reinforced composite material, as well as a method for making said material.

The present disclosure relates to a method for the preparation of a precursor solution for a ceramic of the BZT-aBXT type wherein X is selected from Ca, Sn, Mn and Nb and a is a molar fraction selected in the range between 0.10 and 0.90 comprising the steps of: a) dissolving at least one barium precursor compound and at least one precursor compound selected from the group consisting of a calcium precursor compound, a tin precursor compound, a manganese precursor compound and a niobium precursor compound in a linear or branched anhydrous alkyl alcohol containing from 2 to 6 carbon atoms and, after dissolution, dehydrating by stripping, to obtain a first solution; b) dissolving at least one zirconium precursor compound and at least one titanium precursor compound in a linear or branched anhydrous alkyl alcohol containing from 2 to 6 carbon atoms in the presence of an anhydrous chelating agent to obtain a second solution; c) joining said first and second solutions in an anhydrous environment and dehydrating by stripping to obtain said precursor solution. It also relates to a precursor solution, to a method for the preparation of a film of a piezoelectric material, to a piezoelectric material and to an electronic device comprising this piezoelectric material.

A precursor solution according to the present disclosure contains: an organic solvent; a lithium oxoacid salt that exhibits a solubility in the organic solvent; and a base metal compound that exhibits a solubility in the organic solvent and that is at least one base metal selected from the group consisting of Nb, Ta, and Sb.

It is described a process for producing transparent ceramic bodies with at least two zones having different garnet composition, in particular in which one of said zones has composition Y.sub.3AI.sub.5O.sub.12. The invention is especially useful for the production of transparent ceramic bodies having preset complex shapes and/or a controlled complex distribution of doping ions.

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.

There are provided a composite perovskite powder, a preparation method thereof, and a paste composition for an internal electrode having the same, the composite perovskite powder capable of preventing ions from being eluted from an aqueous system at the time of synthesis while being ultra-atomized, such that when the composite perovskite powder is used as an inhibitor powder for an internal electrode, sintering properties of the internal electrode may be deteriorated, and sintering properties of a dielectric material may be increased; accordingly, connectivity of the internal electrode may be improved, and permittivity and reliability of a multilayer ceramic capacitor (MLCC) may be increased.

A general procedure applied to a variety of sol-gel precursors and solvent systems for preparing and controlling homogeneous dispersions of very small particles within each other. Fine homogenous dispersions processed at elevated temperatures and controlled atmospheres make a ceramic powder to be consolidated into a component by standard commercial means: sinter, hot press, hot isostatic pressing (HIP), hot/cold extrusion, spark plasma sinter (SPS), etc.