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 multilayer coil component including a magnetic part formed of a ferrite material, a non-magnetic part formed of a non-magnetic ferrite material, and a coiled conductive part embedded in the magnetic part and the non-magnetic part. The non-magnetic part has an Fe content of 36.0 to 48.5 mol % in terms of Fe.sub.2O.sub.3, a Zn content of 46.0 to 57.5 mol % in terms of ZnO, a V content of 0.5 to 5.0 mol % in terms of V.sub.2O.sub.5, a Mn content of 0 to 7.5 mol % in terms of Mn.sub.2O.sub.3, and a Cu content of 0 to 5.0 mol % in terms of CuO with respect to the sum of the Fe content in terms of Fe.sub.2O.sub.3, the Zn content in terms of ZnO, the V content in terms of V.sub.2O.sub.5, and if present, the Cu content in terms of CuO, and the Mn content in terms of Mn.sub.2O.sub.3.

A semiconductor ceramic composition which is a BaTiO.sub.3 based semiconductor ceramic composition, wherein, part of Ba is replaced by at least A (at least one alkali metal element selected from Na and K), Bi and RE (at least one element selected from rare earth elements including Y), and part of Ti is replaced by at least TM (at least one element selected from the group including of V, Nb and Ta), the relationships of 0.7≦{(the content of Bi)/(the content of A)}≦1.43, 0.017≦{(the content of Bi)+(the content of A)}≦0.25, and 0<{(the content of RE)+(the content of TM)}≦0.01 are satisfied when the total content of Ti and TM is set as 1 mol, the grain sizes have a maximum peak in a grain size distribution in a range of 1.1 μm to 4.0 μm or less, and the distribution frequency of the peak is 20% or more.

The present invention relates to a kit of parts comprising a dental mill blank comprising a porous zirconia material and a colouring solution for colouring the porous zirconia material. The porous zirconia material comprises Zr oxide calculated as ZrO2: from 80 to 97 wt.-%, Al oxide calculated as Al2O3: from 0 to 0.15 wt.-%, Y oxide calculated as Y2O3: from 1 to 10 wt.-%, Bi oxide calculated as Bi2O3: from 0.01 to 0.2 wt.-%, the porous zirconia material not comprising Fe calculated as Fe2O3 in an amount of more than 0.01 wt.-%, wt.-% with respect to the weight of the porous zirconia material. The colouring solution comprises solvent(s), colouring agent(s) comprising metal ions selected from Tb, Er, Pr, Mn or combinations thereof, the solution not comprising Fe ions in an amount of more than 0.01 wt.-%, the solution not comprising Bi ions in an amount of more than 0.01 wt.-%, wt.-% with respect to the weight of the colouring solution. The invention also relates to a process of producing a dental restoration, the process comprising the steps: providing a dental mill blank comprising a porous zirconia material as described in any of the preceding claims, machining an article out of the porous zirconia material, the article having the shape of a dental restoration with an outer and inner surface, providing a colouring solution as described in any of the preceding claims, applying the colouring solution to at least portions of the surface of the article having the shape of a dental restoration.

A fibrous preform (1) is produced, provided with a sandwich structure comprising an intermediate flexible core (4) and two outer fibrous frames (2, 3), respectively arranged on opposing outer faces of said flexible core (4) and assembled by sections of wire (8, 9) passing through said fibrous frames (2, 3), said preform (1) being impregnated with resin. Said preform is then hardened and the core (4) is removed, preferably by pre-densification with chemical vapour infiltration, and the structure produced is then densified with liquid-phase infiltration.

The present disclosure relates to a dental ceramic article comprising ceramic components, the ceramic components having ZrO2 and Al2O3 and at least one component comprising Mn, Er or mixtures thereof, Al2O3 being present in an amount below about 0.15 wt.-% with respect to the weight of the ceramic article. The present disclosure relates also to kit of parts comprising a ceramic article and a coloring solution and processes for producing a dental ceramic article.

The invention relates to a coloured zirconia ceramic dental mill blank having fluorescing properties, processes of production such a mill blank and uses thereof, in particular for producing zirconia ceramic dental restorations.

The dental mill blank having a shape allowing the dental mill blank to be attached or fixed to a machining device, the dental mill blank comprising a porous zirconia material, the porous zirconia material comprising the oxides Zr oxide calculated as ZrO.sub.2: from about 80 to about 97 wt.-%, Al oxide calculated as Al.sub.2O.sub.3: from about 0 to about 0.15 wt.-%, Y oxide calculated as Y.sub.2O.sub.3: from about 1 to about 10 wt.-%, Bi oxide calculated as Bi.sub.2O.sub.3: from about 0.01 to about 0.20 wt.-%, Tb oxide calculated as Tb.sub.2O.sub.3: from about 0.01 to about 0.8 wt.-%, and optionally one or two of the following oxides: Er oxide calculated as Er.sub.2O.sub.3: from about 0.01 to about 3.0 wt.-%, Mn oxide calculated as MnO.sub.2: from about 0.0001 to about 0.08 wt.-%, wt.-% with respect to the weight of the porous zirconia material.

Provided are metal oxide ceramic materials and intermediate materials thereof (e.g., nanozirconia gels, nanozirconia green bodies, pre-sintered ceramic bodies, zirconia dental ceramic materials, and dental articles). The nanozirconia gels are formable gels. Also provided are methods of making and using the metal oxide materials and intermediate materials. The nanozirconia gels can be made using, for example, osmotic processing. The nanozirconia gels can be used to make nanozirconia green bodies, pre-sintered ceramic bodies, zirconia dental ceramic materials, and dental article. The nanozirconia green bodies, pre-sintered ceramic bodies, zirconia dental ceramic materials, and dental articles have desirable properties (e.g., optical properties and mechanical properties).

Provided is a lithium titanate sintered plate for use in a negative electrode of a lithium secondary battery. The lithium titanate sintered plate has a structure in which a plurality of primary grains are bonded, and has: a thickness of 10 to 290 μm; a primary grain diameter of 0.70 μm or less, the primary grain diameter being a mean grain diameter of the primary grains; a porosity of 21 to 45%; an open pore rate of 60% or more; a mean pore aspect ratio of 1.15 or more; a ratio of 30% or more of pores having an aspect ratio of 1.30 or more to all the pores; and a mean pore diameter of 0.70 μm or less, wherein volume-based D10 and D90 pore diameters satisfy the relationship: 4.0≤D90/D10≤50.