A monolithic refractory castable material comprises from about 25 to about 80 weight percent of graphite, from about 1 to about 15 weight percent of a water dispersible, curable phenolic novolac resin, and from about 70 to about 15 weight percent of one or more refractory aggregates, based on the weight of the monolithic refractory castable material. The monolithic refractory castable material is water dispersible and may be delivered to a structure surface by casting, pumping, shotcreting or gunning processes. In one embodiment, the monolithic refractory castable material may be employed to install or replace a blast furnace lining.

Embodiments of disclosure may provide a method for forming an aluminum-containing nitride ceramic matrix composite, comprising heating a green body, an aluminum-containing composition, ammonia and a mineralizer composition in a sealable container to a temperature between about 400 degrees Celsius and about 800 degrees Celsius and a pressure between about 10 MPa and about 1000 MPa, to form an aluminum-containing nitride ceramic matrix composite characterized by a phosphor-to-aluminum nitride (AlN) ratio, by volume, between about 1% and about 99%, by a porosity between about 1% and about 50%, and by a thermal conductivity between about 1 watt per meter-Kelvin and about 320 watts per meter-Kelvin. The green body comprises a phosphor powder comprising at least one phosphor composition, wherein the phosphor powder particles are characterized by a D50 diameter between about 100 nanometers and about 500 micrometers, and the green body has a porosity between about 10% and about 80%. The aluminum-containing composition has a purity, on a metals basis, between about 90% and about 99.9999%. The fraction of free volume within the sealable container contains between about 10% and about 95% of liquid ammonia prior to heating the green body, the aluminum-containing composition, ammonia and the mineralizer composition in the sealable container.

A functionally graded (FG) SiAlON composite cutting tool includes a cutting head having a cutting surface containing the FG SiAlON composite. The FG SiAlON composite is obtained by sintering one or more powder compositions containing SiO.sub.2 particles having a particle size of 20 to 50 nanometers (nm), AlN particles having a particle size of up to 100 nm, Si.sub.3N.sub.4 particles having a particle size of 300 to 500 nm, Al.sub.2O.sub.3 particles having a particle size of up to 100 nm, Yb.sub.2O.sub.3 particles having a particle size of up to 100 nm, and one or more reinforcement additives selected from the group consisting of cobalt (Co) particles, titanium carbonitride (TiCN) particles, cobalt alloy particles, and a boron nitride compound. The one or more reinforcement additives have an average particle size in a range of 50 nm to 35 micrometers (m).

In joining composite ceramic bodies, at least one ceramic body is a compositionally graded with varying concentrations between two or more ceramic materials. The compositionally graded ceramic body terminates at an interfacial layer that is substantially composed of a single ceramic material. The compositionally graded ceramic body is joined to another ceramic body that may also be compositionally graded or made of a single ceramic material, and an interfacial layer of the other ceramic body is identical in composition with the interfacial layer of the compositionally graded ceramic body. In some embodiments, the ceramic bodies may be joined by diffusion bonding. In some embodiments, the ceramic bodies include a ceramic platen and ceramic stem of a wafer pedestal implemented in a plasma processing apparatus.

A thermal spray coating according to the present invention contains mainly magnesium, aluminum, oxygen, and nitrogen and has, as a main phase, a crystal phase of a MgOAlN solid solution in which aluminum nitride is dissolved with magnesium oxide. The thermal spray coating is obtained by thermal spray of powder of a ceramic material containing mainly magnesium, aluminum, oxygen, and nitrogen and having, as a main phase, a crystal phase of a MgOAlN solid solution in which aluminum nitride is dissolved with magnesium oxide.

A silicon carbide based material exhibiting high strength, good thermal shock resistance, high resistance to abrasion and being chemically stable to harsh environmental conditions is described. The carbide Ball Hill ceramic comprises a -SiAlON bonding phase in which sintering is facilitated by at least one rare earth oxide sintering agents incorporated within the Vibrating Sieve batch admixture as starting materials. The residual rare earth sintering aid being chosen so as to impart good mechanical and refractory properties.

A castable refractory composition may include from 5% to 95% by weight of alumina, aluminosilicate, or mixtures thereof; from 0.5% to 1.5% by weight alkaline earth metal oxide and/or hydroxide, and 0.1% to 5% by weight of silica having a surface area of at least about 10 m.sup.2/g. The refractory composition may include no more than 0.5% by weight of cementitious binder. The refractory composition may release less than 25 cm.sup.3 of hydrogen gas per kilogram of castable refractory composition upon addition of water. The refractory compositions may set on addition of water.

It is provided a sintered body on the basis of -sialon and 15R-sialon, which as a cutting material has a high cutting performance as compared to workpieces made of nickel-based alloy or Heat Resistant Super Alloys. For this purpose, a ceramic sintered body is shown, which includes a sialon phase and an amorphous or semi-crystalline grain boundary phase. The sialon phase includes a proportion of 20-80 wt-% of 15R-sialon polytypoid. The amorphous or semi-crystalline grain boundary phase possibly includes an YbAl garnet and constitutes up to 15 wt-% of the entire sintered body. The sintered body is manufactured from an inorganic raw material mixture which includes 40 to 57 wt-% of Si.sub.3N.sub.4; 40 to 55 wt-% of a mixture of AlN and Al.sub.2O.sub.3, wherein the ratio of Al.sub.2O.sub.3 to AlN lies in the range of 1-1.5:1, and 3 to 5 wt-% of Yb.sub.2O.sub.3 as sintering aid.

A ceramic material that has a high resistivity and high corrosion resistance according to the present invention contains magnesium-aluminum oxynitride and has a carbon content of 0.005 to 0.275 mass %.

A cutting tool (1) formed of a silicon nitride-based sintered body (2) including a matrix phase (3), a hard phase (4), and a grain boundary phase (10) in which a glass phase (11) and a crystal phase (12) exist. The sintered body (2) contains yttrium in an amount of 5.0 wt % to 15.0 wt % in terms of an oxide, and contains titanium nitride as the hard phase (4) in an amount of 5.0 wt % to 25.0 wt %. In an X-ray diffraction peak, a halo pattern appears at 2 ranging from 25 to 35 in an internal region of the sintered body (2). A ratio B/A of a maximum peak intensity B to a maximum peak intensity A satisfies 0.11B/A0.40 . . . Expression (1) in a surface region of the sintered body (2), and satisfies 0.00B/A0.10 . . . Expression (2) in the internal region of the sintered body (2).