The invention relates to a refractory batch, to a method for producing an unshaped refractory ceramic product from the batch, and to an unshaped refractory ceramic product obtained by said method.

A graphite-containing refractory has higher bending strength and fracture energy than known refractories. The graphite-containing refractory has a graphite content of 1% to 80% by mass. 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 m/fiber are bundled. The carbon fiber bundle has a length of 100 mm or more and is placed within the graphite-containing refractory to form the same.

In a monolithic refractory, in terms of a proportion in 100 mass % of a refractory raw material having a grain size of 8 mm or smaller, an amount of Ca.sub.XSr.sub.1XAl.sub.2O.sub.4 (where, 0X0.5) is 0.5 mass % or more and 10 mass % or less, and a polyvalent metal salt of oxycarboxylic acid is 0.05 mass % or more and 1.0 mass % or less.

Disclosed herein are methods for making a bonded refractory material, the methods comprising preparing a slurry comprising glass precursor particles having an average particle size ranging from about 1 nm to about 200 nm; combining zirconia particles with the slurry to form a batch composition comprising at least about 80% by weight of zirconia; forming a green body from the batch composition; and sintering the green body to form a sintered refractory material. Sintered high-zirconia refractory materials can comprise at least about 80% by weight of zirconia having an average grain size of 100 microns or less, wherein the zirconia is interspersed in a glassy phase, and wherein the sintered refractory materials comprise about 15% or less by weight of the glassy phase. Melting vessels having at least one interior surface comprising such sintered zirconia refractory materials are further disclosed herein.

A ceramic foam filter and a manufacturing method thereof. The ceramic foam filter comprises the following materials provided in respective weight percentages: 20-50% of a silicon carbide, 20-55% of a zirconium oxide, and 10-36% of a silicon oxide, wherein all figures are based on the total weight of the ceramic foam filter. The method for manufacturing the ceramic foam filter comprises the following steps: (a) providing a slurry comprising a silicon carbide, a zirconium oxide or zirconium oxide precursor, a silicon oxide or silicon oxide precursor, a binder, an optional additive, and a fluid carrier medium; (b) applying the slurry to perform surface ornamentation of a perforated organic foam; (c) drying the perforated organic foam surface ornamented with the slurry to obtain a green body; and (d) sintering the green body in oxygen-containing air to obtain the ceramic foam filter.

A ceramic foam filter for use in filtering non-ferrous metals and manufacturing method for same are disclosed. The ceramic foam filter includes calcined alumina as a core material and silica as a binder. Alternatively, the ceramic foam filter includes calcined alumina as a core material and boric oxide as a binder.

Methods for forming ceramic cores are disclosed. A ceramic core formed using the method of the present application includes a silica depletion zone encapsulating an inner zone. The inner zone includes mullite and the silica depletion zone includes alumina. The method includes heat-treating a ceramic body in a non-oxidizing atmospheric condition for an effective temperature and time combination at a pressure less than 10.sup.2 atmosphere to form the silica depletion zone at a surface of the ceramic core.

Provided is a hearth roll for supporting and conveying a steel sheet in a continuous annealing furnace, wherein all of a shaft portion and a roil main body are made from one or more ceramic materials, preferably constituted with concentric ceramic layers of different ceramic materials centering on the rotation shaft of the roll. The hearth roll has not only an excellent pickup resistance but also a long roll life free from maintenance for long periods. Also provided is a continuous annealing facility using the hearth roll in at least one of a heating zone, a soaking zone and a cooling zone.

A foundry media pellet includes a sintered ceramic material having a size from about 10 AFS GFN to about 110 AFS GFN, and a surface roughness of less than about 4 microns.

A coating liquid for preparing a needle-shaped cylinder liner, comprising the following components: 0.05-0.4 parts of an anionic surfactant; 0.05-0.5 parts of tannic acid; 0.15-0.7 parts of caustic soda; 22-38 parts of diatomite; 3-10 parts of montmorillonite; and 62-75 parts of water. A method for preparing a needle-shaped cylinder liner comprises spraying a coating liquid for preparing the needle-shaped cylinder liner onto the inner wall of a hollow cylindrical mould, and drying the coating liquid to obtain a mould with a coating attached to the surface of the inner wall; adding an inoculated iron liquid into the rotary mould, and cooling and demoulding to obtain a cylinder liner blank; and subjecting the blank to outer surface cleaning and forming machining to obtain the needle-shaped cylinder liner.