The invention relates to a grain for production of a refractory product, to the use of such grains, to a refractory product, to a process for producing a refractory product and to a refractory product produced thereby.

A part made of composite material includes fiber reinforcement including silicon carbide fibers presenting an oxygen content less than or equal to 1 % in atomic percentage; and a matrix present in the pores of the fiber reinforcement and including at least one sintered silicate phase including at least one rare earth silicate, mullite, or a mixture of mullite and of at least one rare earth silicate, the matrix including at least a first phase including mullite and a second phase, different from the first phase, including at least one rare earth silicate.

A chromia-based brick, having chromia as a main component, includes: 70 to 95 mass % of Cr.sub.2O.sub.3; 0.5 to 15 mass % of ZrO.sub.2; 0.4 to 4.0 mass % of P.sub.2O.sub.5 derived from phosphate added as raw material; 10 or lower mass % of Al.sub.2O.sub.3; and a sintering aid component and unavoidable components.

A high zirconia electrically-fused cast refractory has a chemical composition including more than 95% by mass and 98% by mass or less of ZrO.sub.2, 0.1 to 1.5% by mass of Al.sub.2O.sub.3, 1 to 2.5% by mass of SiO.sub.2, 0 to 0.1% by mass of K.sub.2O, 0.01 to 0.3% by mass of Na.sub.2O and K.sub.2O in total, 0.02 to 0.4% by mass of B.sub.2O.sub.3, 0.01 to 0.6% by mass of BaO, 0.01 to 0.4% by mass of SnO.sub.2, 0.3% by mass or less of Fe.sub.2O.sub.3 and TiO.sub.2 in total, and 0.04% by mass or less of P.sub.2O.sub.5, wherein the contents of B.sub.2O.sub.3 and SnO.sub.2 satisfy the following Formulas (1) and (2):

0.20(SnO.sub.2/B.sub.2O.sub.3)<6.5(1)

0.14% by mass(C.sub.SnO2+C.sub.B2O3/2)0.55% by mass(2):

In Formula (2), C.sub.SnO2 represents the content of SnO.sub.2, and C.sub.B2O3 represents the content of B.sub.2O.sub.3, expressed in % by mass in the refractory.

An article comprises a plasma resistant ceramic material comprising Y.sub.2O.sub.3 at a concentration of approximately 30 molar % to approximately 60 molar %, Er.sub.2O.sub.3 at a concentration of above 30 molar % to approximately 60 molar %, and at least one of ZrO.sub.2, Gd.sub.2O.sub.3 or SiO.sub.2 at a concentration of over 0 molar % to approximately 30 molar %.

The use of magnesium oxide, reactive alumina and aluminium oxide as a base provides for a new erosion-resistant material upon sintering.

The invention relates to a batch composition for producing a carbon-bonded refractory stone, a method for producing a carbon-bonded refractory stone, and use of Ti.sub.2AlC.

A powder formed of fused particles. More than 95% by number of the feed particles exhibiting a circularity of greater than or equal to 0.85. The powder contains more than 88% of a silicate of one or more elements chosen from Zr, Hf, Y, Ce, Sc, In, La, Gd, Nd, Sm, Dy, Er, Yb, Eu, Pr, Ho and Ta, less than 10% of a dopant, as percentage by weight based on the oxides. The powder has a median particle size D.sub.50 of less than 15 m, a 90 percentile particle size, D.sub.90, of less than 30 m, and a size dispersion index (D.sub.90-D.sub.10)/D.sub.10 of less than 2. The powder has a relative density of greater than 90%. The D.sub.n percentiles of the powder are the particle sizes corresponding to the percentages, by number, of n %, on the cumulative distribution curve of the size of the particles of the powder. The particle sizes are classified in increasing order.

The present invention provides a high alumina fused cast refractory that is easily produced and has low porosity and high corrosion resistance, and a method of producing the same. The high alumina fused cast refractory of the present invention has the following chemical composition: 95.0 mass % to 99.5 mass % Al.sub.2O.sub.3, 0.20 mass % to 1.50 mass % SiO.sub.2, 0.05 mass % to 1.50 mass % B.sub.2O.sub.3, 0.05 mass % to 1.20 mass % MgO and balance. The method of producing the high alumina fused cast refractory of the present invention includes obtaining a mixture by mixing an Al.sub.2O.sub.3 source material, a SiO.sub.2 source material, a B.sub.2O.sub.3 source material and an MgO source material, and fusing the mixture.

Disclosed is a method of making high temperature fiber including incorporating an inorganic atom into a polymer precursor fiber to form a modified polymer precursor fiber and converting the modified polymer precursor fiber to a high temperature fiber having a bonded inorganic atom.