The electrolyte membrane of the present disclosure includes a plurality of crystal domains. At least one of the crystal domains includes a first crystal subdomain and a second crystal subdomain. Each of the first crystal subdomain and the second crystal subdomain includes Ba, Zr, M, and O. M is a trivalent element. The concentration of M in the first crystal subdomain is different from the concentration of M in the second crystal subdomain.

A preparation method of an alumina ceramic valve core ceramic chip and a product thereof. The alumina ceramic valve core ceramic chip is obtained by the steps of mixing alumina, a sintering aid and a toughening agent according to a raw material ratio, ball-milling, drying, cold isostatic pressing, sintering and the like. The alumina ceramic valve core ceramic chip is prepared by adopting nano alumina and zirconium oxide as the sintering aid, so that the material has excellent bending strength, fracture toughness, hardness and low wear rate, the bending strength can reach 357.8-360.06 MPa, the fracture toughness is 4.32-4.56 MPa.sup.1/2, the Vickers hardness is 1592.7-1614.8 MPa. the wear rate is 0.04-0.09%, and the alumina ceramic valve core ceramic chip is an ideal material for preparing a faucet valve core.

A method for producing a component includes a) providing at least two preforms each made of a carbon composite material, b) joining the at least two preforms at least at one respective connecting surface to form a composite, in which a joining compound is introduced between the joining surfaces of the preforms and then cured and the joining compound contains silicon carbide and at least one polymer adhesive, and c) siliconizing the composite to form the component. A component, such as an optical component produced thereby, is also provided.

A method for producing a ceramic multilayer element is disclosed. In an embodiment the method includes forming a plurality of multilayer segments in a green state, wherein each multilayer segment is formed by pressing together a plurality of ceramic layers in the green state and pressing together the multilayer segments in the green state to form a multilayer element that is in the green state. The method further includes sintering the multilayer element that is in the green state to form a ceramic multilayer element that includes the ceramic layers and electrode layers arranged one on top of another, wherein at least one or more of a temperature at which the multilayer segments are pressed together, a pressing force applied during the pressing of the multilayer segments, and/or a duration of the pressing of the multilayer segments are adjusted.

A hard material which, when used as a material of a sintered material, makes it possible to obtain a sintered material with excellent abrasion resistance, a sintered material, a cutting tool including the sintered material, a method for manufacturing the hard material and a method for manufacturing the sintered material are provided. The hard material contains aluminum, nitrogen, and at least one element selected from the group consisting of titanium, chromium, and silicon, and has a cubic rock salt structure.

A sialon sintered body and a cutting insert each having thermal shock resistance and VB wear resistance. The sialon sintered body and the cutting insert contain β-sialon and 21R-sialon and exhibit an X-ray diffraction peak intensity ratio R[(I.sub.21R/I.sub.A)×100] of 5% or greater and smaller than 30%, wherein I.sub.A represents the sum of the peak intensities of the sialon species, and I.sub.21R represents the peak intensity of 21R-sialon, the ratio being calculated from the peak intensities of the sialon species obtained by using X-ray diffractometry.

A production method for a ceramic matrix composite is comprised of: compounding an aggregate powder including a ceramic and a binder including at least one of thermoplastic resins and waxes to form a composition of the aggregate powder and the binder; pressing the composition to form sheets; accumulating fabrics of reinforcement fibers including the ceramic and the sheets alternately; pressing an accumulated body of the fabrics and the sheets; and generating a matrix combining the reinforcement fibers together.

Provided are a sintered ceramic and a ceramic sphere which are inhibited from suffering surface peeling due to fatigue resulting from repetitions of loading and can attain an improvement in dimensional accuracy when subjected to surface processing and which have excellent wear resistance and durability.

A ceramic substrate and a method for production thereof are provided, in which the ceramic substrate includes a composite of : a first ceramic layer including Sr anorthite and Al.sub.2O.sub.3 or an oxide dielectric with a dielectric constant higher than that of Al.sub.2O.sub.3; and a second ceramic layer including Sr anorthite and cordierite and having a dielectric constant lower than that of the first ceramic layer.

A prosthesis that contains zirconia and supplements a defective portion of a natural bone, and that is changed to a color approximate to that of the natural bone by a heat treatment after a γ-ray sterilization treatment. The color approximate to that of the natural bone has an L* value of 60 to 90, an a* value of −5 to 10, and a b* value of −5 to 10 in the L*a*b* color space. The highest temperature in the heat treatment is 100° C. to 300° C. The prosthesis is a fixture of a dental implant embedded into and bonded to a natural bone, an abutment, an implant crown, and the like.