The present disclosure relates to ultra-high density concrete composite containing super-absorbent polymer (SAP)-Attached Fibers, suitable for making a near-vacuum tube for hyperloop transportation system, a method for manufacturing the ultra-high density concrete composite, a method for manufacturing a concrete member using the ultra-high density concrete composite and an ultra-high density concrete member manufactured by the method.

Disclosed are a sagger for sintering lithium composite transition metal oxide and a preparation method thereof. The sagger includes a substrate layer and a shallow layer on a surface of the substrate layer, and a coating layer. The substrate layer is prepared from the following raw materials: silicon carbide, magnesia-alumina spinel, aluminum oxide-magnesium oxide-yttrium oxide composite fiber, zircon powder and a binding agent; the shallow layer is prepared from the following raw materials: silicon carbide, magnesia-alumina spinel, aluminum oxide-titanium oxide composite fiber, yttrium oxide-zirconium oxide composite fiber and a binding agent; and the coating layer is prepared from the following raw materials: silicon carbide, magnesia-alumina spinel, magnesium oxide, zirconium oxide fiber, lithium composite transition metal oxide powder and a binding agent. The sagger of the present disclosure has properties of good corrosion resistance and a small coefficient of thermal expansion.

A method of producing a ceramic matrix composite including a protective ceramic coating thereon comprises applying a surface slurry onto an outer surface of an impregnated fiber preform. The surface slurry includes particulate ceramic solids dispersed in a flowable preceramic polymer comprising silicon, and the impregnated fiber preform comprises a framework of ceramic fibers loaded with particulate matter. The flowable preceramic polymer is cured, thereby forming on the outer surface a composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein. The cured preceramic polymer is then pyrolyzed to form a porous ceramic layer comprising silicon carbide, and the impregnated fiber preform and the porous ceramic layer are infiltrated with a molten material comprising silicon. After infiltration, the molten material is cooled to form a ceramic matrix composite body with a protective ceramic coating thereon.

A method of producing a ceramic matrix composite including a protective ceramic coating thereon comprises applying a surface slurry onto an outer surface of an impregnated fiber preform. The surface slurry includes particulate ceramic solids dispersed in a flowable preceramic polymer comprising silicon, and the impregnated fiber preform comprises a framework of ceramic fibers loaded with particulate matter. The flowable preceramic polymer is cured, thereby forming on the outer surface a composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein. The cured preceramic polymer is then pyrolyzed to form a porous ceramic layer comprising silicon carbide, and the impregnated fiber preform and the porous ceramic layer are infiltrated with a molten material comprising silicon. After infiltration, the molten material is cooled to form a ceramic matrix composite body with a protective ceramic coating thereon.

An asphalt-cement concrete (“ACC”) interlayer formed of a plant-mix material reinforced with aramid fibers, deposited at a thickness of at least one inch (1″) over a Portland-cement concrete (“PCC”) or ACC base, can extend the service life of a hot-mix asphalt (“HMA”) surface layer installed over the interlayer by retarding or preventing “reflected” cracks—cracks in the surface layer that correspond to cracks, damage and irregularities in the PCC or ACC base. When the surface layer's useable life has expired, it can be removed and replaced, and the interlayer can continue to protect the new surface layer.

Provided are a coating structure, a turbine part having the same, and a method for manufacturing the coating structure. The coating structure is provided on a surface of a base portion including a ceramic matrix composite. The coating structure is layered on the surface of the base portion, and includes a bond coat layer formed of a rare-earth silicate and a top coat layer layered on the bond coat layer. The residual stress present in the bond coat layer is compressive residual stress. The oxygen permeability coefficient of the bond coat layer is no greater than 10.sup.−9 kg.Math.m.sup.−1.Math.s.sup.−1 at a temperature of not lower than 1200° C. and a higher oxygen partial pressure of not less than 0.02 MPa. The bond coat layer may contain carbonitride particles or carbonitride whiskers.

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 process for manufacturing an abradable layer, includes compressing a powder composition including at least micrometric ceramic particles having a number-average form factor greater than or equal to 3, a mass content of said micrometric ceramic particles in the powder composition being greater than or equal to 85%, the form factor of a particle being defined as the ratio [largest dimension of the particle]/[largest cross-sectional dimension of the particle], and sintering the powder composition thus compressed to obtain the abradable layer, wherein a temperature imposed during sintering, the sintering time and the compression pressure applied are selected so as to obtain a volume porosity rate of the abradable layer greater than or equal to 20%.

A process for manufacturing an abradable layer, includes compressing a powder composition including at least micrometric ceramic particles having a number-average form factor greater than or equal to 3, a mass content of said micrometric ceramic particles in the powder composition being greater than or equal to 85%, the form factor of a particle being defined as the ratio [largest dimension of the particle]/[largest cross-sectional dimension of the particle], and sintering the powder composition thus compressed to obtain the abradable layer, wherein a temperature imposed during sintering, the sintering time and the compression pressure applied are selected so as to obtain a volume porosity rate of the abradable layer greater than or equal to 20%.

A method of producing a ceramic matrix composite including a protective ceramic coating thereon comprises applying a surface slurry onto an outer surface of an impregnated fiber preform. The surface slurry includes particulate ceramic solids dispersed in a flowable preceramic polymer comprising silicon, and the impregnated fiber preform comprises a framework of ceramic fibers loaded with particulate matter. The flowable preceramic polymer is cured, thereby forming on the outer surface a composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein. The cured preceramic polymer is then pyrolyzed to form a porous ceramic layer comprising silicon carbide, and the impregnated fiber preform and the porous ceramic layer are infiltrated with a molten material comprising silicon. After infiltration, the molten material is cooled to form a ceramic matrix composite body with a protective ceramic coating thereon.