Ceramic matrix composite articles include, for example a first plurality of plies of ceramic fibers in a ceramic matrix defining a first extent, and a local at least one second ply in said ceramic matrix defining a second extent on and/or in said first plurality of plies with the second extent being less than said first extent. The first plurality of plies has a first property, the at least one second ply has at least one second property, and said first property being different from said at least one second property. The different properties may include one or more different mechanical (stress/strain) properties, one or more different thermal conductivity properties, one or more different electrical conductivity properties, one or more different other properties, and combinations thereof.

Disclosed herein are embodiments of low temperature co-fireable scheelite materials which can be used in combination with high dielectric materials, such as nickel zinc ferrite, to form composite structures, in particular for isolators and circulators for radiofrequency components. In some embodiments, the scheelite material can include aluminum oxide for temperature expansion regulation.

A method of manufacturing a ceramic matrix composite component includes placing a first impregnated fiber layer on a surface, aligning a second impregnated fiber layer with the first impregnated fiber layer, and joining the first impregnated fiber layer with the second impregnated fiber layer at a plurality of discrete joining regions. The joining of the first and second impregnated fiber layers comprises transferring energy from at least one tool into the first and second impregnated fiber layers at the plurality of discrete joining regions.

A method for manufacturing an electrostatic chuck with multiple chucking electrodes made of ceramic pieces using metallic aluminum as the joining. The aluminum may be placed between two pieces and the assembly may be heated in the range of 770 C to 1200 C. The joining atmosphere may be non-oxygenated. After joining the exclusions in the electrode pattern may be machined by also machining through one of the plate layers. The machined exclusion slots may then be filled with epoxy or other material. An electrostatic chuck or other structure manufactured according to such methods.

A process for the manufacture of inorganic fibres comprises: (a) selecting a composition and proportion of: (i) silica sand; (ii) lime comprising at least 0.10 wt % magnesia; and (iii) optional additives comprising a source of oxides or non-oxides of one or more of the lanthanides series of elements, or combinations thereof; (b) mixing the silica sand; lime; and optional additives to form a mixture; (c) melting the mixture in a furnace; and (d) shaping the molten mixture into inorganic fibres. The raw materials selection comprises composition selection and proportion selection of the raw materials to obtain an inorganic fibre composition comprising a range of from 61.0 wt % and 70.8 wt % silica; less than 2.0 wt % magnesia; less than 2.0% incidental impurities; and no more than 2.0 wt % of metal oxides and/or metal non-oxides derived from said optional additives; with calcia providing the balance up to 100 wt %; and wherein the inorganic fibre composition comprises no more than 0.80 wt % Al.sub.2O.sub.3 derived from the incidental impurities and/or the optional additives.

Disclosed herein are embodiments of low temperature co-fireable dielectric materials which can be used in conjunction with high dielectric materials to form composite structures, in particular for isolators and circulators for radiofrequency components. Embodiments of the low temperature co-fireable dielectric materials can be scheelite or garnet structures, for example, bismuth vanadate. Adhesives and/or glue is not necessary for the formation of the isolators and circulators.

Disclosed is a method for manufacturing a ceramic susceptor, the method including: preparing ceramic sheets; preparing a lamination structure of a molded body, in which the ceramic sheets are laminated and a conductive metal layer for electrodes is disposed between the ceramic sheet laminated products; and sintering the lamination structure of the molded body, wherein the preparing of the ceramic sheets includes: obtaining a vitrified first additive powder by heat-treating a slurry containing MgO, SiO.sub.2, and CaO; preparing a slurry by mixing an Al.sub.2O.sub.3 powder with the first additive powder, a second additive powder containing a MgO powder, and a third additive powder containing a Y.sub.2O.sub.3 powder; and forming the ceramic sheets by tape casting the slurry.

An improved ceramic material for heat insulation with selection of specific stabilizers and adapted proportions, includes zirconium oxide with 0.2 wt. % to 8.0 wt. % of the base stabilizers: yttrium oxide (Y.sub.2O.sub.3), hafnium oxide (HfO.sub.2), cerium oxide (CeO.sub.2), calcium oxide (CaO), and/or magnesium oxide (MgO), wherein at least yttrium oxide (Y.sub.2O.sub.3) is used, and optionally at least one of the additional stabilizers: 0.2 wt. % to 20 wt. % of erbium oxide (Er.sub.2O.sub.3) and/or ytterbium oxide (Yb.sub.2O.sub.3).

An AlN joined body includes a first AlN member and a second AlN member that are joined together. The content of yttria in the first AlN member is equal to or below the detection limit. The second AlN member contains yttria.

The ceramic joint body according to the present disclosure includes: a first member made of ceramic and including a first flow channel configured to feed fluid; and a second member made of ceramic and including a second flow channel connected to the first flow channel to feed the fluid. The ceramic includes zirconium oxide and aluminum oxide, and at least one of the zirconium oxide and the aluminum oxide is a primary constituent, and a first opposing surface of the first member, which faces the second member, and a second opposing surface of the second member, which faces the first member, are connected by diffusion bonding.