An outer periphery coating material being coated onto an outer peripheral surface of a ceramic honeycomb structure to form an outer periphery coated layer. The outer periphery coating material comprises: a particle mixture containing cordierite particles and amorphous silica particles in a mass ratio of from 40:60 to 80:20; and from 10 to 30% by mass of crystalline inorganic fibers in an outer percentage relative to the particle mixture. An average particle diameter of the cordierite particles is different from an average particle diameter of the amorphous silica particles.

An outer periphery coating material being coated onto an outer peripheral surface of a ceramic honeycomb structure to form an outer periphery coated layer. The outer periphery coating material comprises: a particle mixture containing cordierite particles and amorphous silica particles in a mass ratio of from 40:60 to 80:20; and from 10 to 30% by mass of crystalline inorganic fibers in an outer percentage relative to the particle mixture. An average particle diameter of the cordierite particles is different from an average particle diameter of the amorphous silica particles.

A composite material containing a matrix and a fibrous reinforcement, in particular a textile embedded in the matrix. The matrix includes a geopolymer of the poly(phospho-sialate) type having the following formula I: (1) (—P—O—Si—O—Al—O—).sub.n in which n is greater than 2. The matrix further includes zirconium covalently bonded to the matrix, especially in the —ZrO form and/or in the —O—Zr—O form. The matrix has a melting temperature greater than 700° C., especially equal to or greater than 1200° C.

A composite material containing a matrix and a fibrous reinforcement, in particular a textile embedded in the matrix. The matrix includes a geopolymer of the poly(phospho-sialate) type having the following formula I: (1) (—P—O—Si—O—Al—O—).sub.n in which n is greater than 2. The matrix further includes zirconium covalently bonded to the matrix, especially in the —ZrO form and/or in the —O—Zr—O form. The matrix has a melting temperature greater than 700° C., especially equal to or greater than 1200° C.

Moulded insulation bodies, processes for the production thereof and use thereof consisting essentially of ceramic material comprising SiO.sub.2 fibers and Al.sub.2O.sub.3 fibers which has been produced using Al.sub.2O.sub.3 sol as a binder and kilned at a temperature of above 800° C. for insulation of the ends of cracking tubes of a tubular reactor for performing a steam reforming process for generating synthesis gas which project out of the reactor heating space.

Moulded insulation bodies, processes for the production thereof and use thereof consisting essentially of ceramic material comprising SiO.sub.2 fibers and Al.sub.2O.sub.3 fibers which has been produced using Al.sub.2O.sub.3 sol as a binder and kilned at a temperature of above 800° C. for insulation of the ends of cracking tubes of a tubular reactor for performing a steam reforming process for generating synthesis gas which project out of the reactor heating space.

A porous refractory in the K.sub.2O—SiO.sub.2—B.sub.2O.sub.3 system is formed by chemical direct foaming by heating to over 600° C., resulting in adherent black or white foam. The foam can function as highly porous thermal insulation, a high or low thermal emissivity surface, as a sealant for deteriorated refractory surfaces, as a filler for pockmarks/holes/gaps or as a bonding agent for parts with large gaps between them.

A porous refractory in the K.sub.2O—SiO.sub.2—B.sub.2O.sub.3 system is formed by chemical direct foaming by heating to over 600° C., resulting in adherent black or white foam. The foam can function as highly porous thermal insulation, a high or low thermal emissivity surface, as a sealant for deteriorated refractory surfaces, as a filler for pockmarks/holes/gaps or as a bonding agent for parts with large gaps between them.

There is provided a fiber-reinforced brittle matrix composite. The fiber-reinforced brittle matrix composite comprises a brittle matrix material (for example, a cementitious or ceramics material) and a coated fiber embedded in the brittle matrix material, wherein the coated fiber comprises a fiber (for example, polyethylene fiber, glass fiber, silicon carbide fiber, alumina fiber, mullite fiber) and a coating material (for example, carbon nanofibers, carbon nanotubes), which is non-covalently disposed on the fiber. A method for producing the fiber-reinforced brittle matrix composite is also provided. The method comprises providing a fiber, disposing a coating material on the fiber to form a coated fiber, wherein the coating material is non-covalently disposed on the fiber, and embedding the coated fiber in a brittle matrix material to obtain the fiber-reinforced brittle matrix composite.

There is provided a fiber-reinforced brittle matrix composite. The fiber-reinforced brittle matrix composite comprises a brittle matrix material (for example, a cementitious or ceramics material) and a coated fiber embedded in the brittle matrix material, wherein the coated fiber comprises a fiber (for example, polyethylene fiber, glass fiber, silicon carbide fiber, alumina fiber, mullite fiber) and a coating material (for example, carbon nanofibers, carbon nanotubes), which is non-covalently disposed on the fiber. A method for producing the fiber-reinforced brittle matrix composite is also provided. The method comprises providing a fiber, disposing a coating material on the fiber to form a coated fiber, wherein the coating material is non-covalently disposed on the fiber, and embedding the coated fiber in a brittle matrix material to obtain the fiber-reinforced brittle matrix composite.