An automated preparation method of a SiC.sub.f/SiC composite flame tube, comprising the following steps: preparing an interface layer for a SiC fiber by a chemical vapor infiltration process, and obtaining the SiC fiber with a continuous interface layer; laying a unidirectional tape on the SiC fiber with the continuous interface layer and winding the SiC fiber with the continuous interface layer to form and obtaining a preform of a net size molding according to a fiber volume and a fiber orientation obtained in a simulation calculation; and adopting a reactive melt infiltration process and the chemical vapor infiltration process successively for a densification and obtaining a high-density SiC.sub.f/SiC composite flame tube in a full intelligent way. The SiC.sub.f/SiC composite flame tube prepared by the present disclosure not only has a high temperature resistance, but also has a low thermal expansion coefficient, high thermal conductivity and high thermal shock resistance.

A grain-oriented M-type hexagonal ferrite has the formula MeFe.sub.12O.sub.19, and a dopant effective to provide planar magnetic anisotropy and magnetization in a c-plane, or a cone anisotropy, in the hexagonal crystallographic structure wherein Me is Sr.sup.+, Ba.sup.2+ or Pb.sup.2+, and wherein greater than 30%, preferably greater than 80%, of c-axes of the ferrite grains are aligned perpendicular to the c-plane.

An object of the present invention is to provide a sputtering target that can suppress a generation amount of fine nodules which lead to an increase in substrate particles during sputtering, and a method for producing the same. A ceramic sputtering target, the sputtering target having a surface roughness Ra on a sputtering surface of 0.5 μm or less and an Svk value measured with a laser microscope on the sputtering surface of 1.1 μm or less.

The sintered body has an average particle size in the range of 0.1 μm or more and 5 μm or less, includes gamet-type oxide base material particles having at least Li, La, and Zr, has 8% by volume or more of voids, and has an ionic conductivity of 1.0×10.sup.−5 S/cm or more at temperature of 25° C.

Composite structures are provided whose composite matrix is a fully-dense (greater than 95%) magnesium oxide-containing phase and whose entrained phase, by virtue of its' decomposition temperature or chemical reactivity, would otherwise not be fabricable. Notably, a methodology is provided whereby a range of composite structures are formed by applying an advanced manufacturing technique and a blend of ceramic powder whose sintering is enhanced by small amounts of a metal halide sintering aid. This methodology and process significantly lowers the processing temperature of refractory ceramics such as magnesium oxide allowing formation of ceramic bodies incorporating phases such as metal hydrides, fragile ceramic phases, and highly reactive species such as beryllides. In all cases, the final product is substantially-free, or even devoid, of the metal halide sintering aid, resulting in a phase-pure ceramic matrix composed of the host phase and the entrained phase.

An example method includes combining an interlayer and a carbon fiber fabric, wherein the interlayer comprises a highly oriented milled carbon fiber ply comprising a plurality of out-of-plane carbon fibers. The method further includes winding the interlayer and the carbon fiber fabric around a core to form a composite fiber preform comprising a plurality of layers defining an annulus extending along a central axis. The method further includes densifying the composite fiber preform.

Embodiments relate to an improved hydroflux assisted densification process that introduces a transport phase (formed by the introduction of water during the process to suppress melting temperatures) for sintering, the transport phase being a non-aqueous solution. The process can facilitate sintering at low temperature ranges (at or below 300° C.) to yield densification>90% without the need for additional post-processing steps that otherwise would be needed if conventional processes were used. Control of the pressures and water content used during the process can enhance densification mechanisms related to dissolution-reprecipitation, allowing for a greater range of compositional spectra of materials that can be densified, a reduction of the amount of transport phase needed, a reduction of impurities and an improvement of properties in the densified material. Certain hydrated acetate powders can be used to generate a hydroxide mixture flux that is better for the low-temperature densification process.

A ceramic composite can include a first ceramic phase and a second ceramic phase. The first ceramic phase can include a silicon carbide. The second phase can include a boron carbide. In an embodiment, the silicon carbide in the first ceramic phase can have a grain size in a range of 0.8 to 200 microns. The first phase, the second phase, or both can further include a carbon. In another embodiment, at least one of the first ceramic phase and the second ceramic phase can have a median minimum width of at least 5 microns.

A method for producing a ceramic composite includes: preparing a sintered body in a plate form containing a fluorescent material having a composition of a rare earth aluminate, and aluminum oxide; and eluting the aluminum oxide from the sintered body by contacting the sintered body with a basic substance, for example, contained in an alkali aqueous solution, and the dissolution amount of the fluorescent material eluted from the sintered body in the step of eluting the aluminum oxide is 0.5% by mass or less based on an amount of the fluorescent material contained in the sintered body as 100% by mass.

A dielectric composition includes main phases and Ca-RE-Si—O segregation phases. The main phases include a main component expressed by ABO.sub.3. “A” includes at least one selected from barium and calcium. “B” includes at least one selected from titanium and zirconium. “RE” represents at least one of rare earth elements. A molar ratio of (Si/Ca) is larger than one. A molar ratio of (Si/RE) is larger than one, provided that the molar ratio of (Si/RE) is a molar ratio of silicon included in the segregation phases to the rare earth elements included therein. An average length of major axes of the segregation phases is 1.30-2.80 times as large as an average particle size of the main phases. An average length of minor axes of the segregation phases is 0.21-0.48 times as large as an average particle size of the main phases.