A kind of preparation method of high temperature resistant reinforced toughened alumina fiber reinforced alumina matrix composite material

Abstract

The invention discloses a method for preparing a high-temperature-resistant reinforced and toughened Ox / Ox composite material, and relates to the technical field of ceramic-based composite materials. The present invention first adopts the mixed solution of ammonium dichromate and anhydrous oxalic acid to pre-treat the alumina fiber fabric by impregnation-heat treatment to obtain the surface-coated alumina fiber, and then put it into CVI to prepare pyrolytic carbon coating or BN coating. The nanowire coating is obtained by electrophoretic deposition on the coating, and then the alumina ceramic slurry is coated on the surface of the alumina fiber fabric with the nanowire coating for hot pressing and sintering to obtain a high-performance Ox / Ox composites. The invention provides a method for preparing a high-temperature-resistant reinforced and toughened Ox / Ox composite material, which obtains a high-density matrix and a porous nano-oxide coating, so that a weak interface is formed between the alumina fiber and the alumina matrix, thereby obtaining A high-strength, high-toughness, high-temperature-resistant alumina fiber-reinforced alumina matrix composite was developed.

Description

technical field [0001] The invention belongs to the technical field of ceramic matrix composite materials, and in particular relates to a method for preparing a high-temperature-resistant reinforced and toughened Ox / Ox composite material, that is, a method for preparing a high-temperature-resistant reinforced and toughened alumina fiber-reinforced alumina matrix composite material. Background technique [0002] Ceramic matrix composites are a type of composite material that is composited with ceramics and various fibers. The ceramic matrix can be high-temperature structural ceramics such as alumina, silicon nitride, and silicon carbide. At present, alumina is the most widely used and widely used. ceramic matrix composites. Ceramic matrix composites have been used as liquid rocket engine nozzles, missile radomes, space shuttle nose cones, aircraft brake discs and high-end automobile brake discs, etc., becoming an important branch of high-tech new materials. Alumina ceramics ...

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Problems solved by technology

[0004] Chinese invention patent CN201611216535.8 discloses a preparation method of continuous alumina fiber-reinforced alumina ceramic matrix composites. The densification process of the matrix adopts a freeze-drying process, which can not only obtain a high-density matrix, but also ensure that the interface layer is maintained before high-temperature heat treatment. Without cracking, the porous oxide coating is obtained, and a weak interface is formed between the fiber of the composite material and the matrix to achieve the effect of strengthening and toughening the composite material. However, the composite material does not improve the matrix, and the matrix prepared by low-temperature sintering does not dense, the matrix is ​​not completely sintered, and the mechanical properties are poor

Chinese invention patent CN201910715241.7 discloses a method for preparing alumina fiber-reinforced alumina ceramic matrix composites. During the sintering process, the carbon-containing coating is oxidized and decomposed to generate a gap interface layer between the fiber and the matrix, avoiding The damage of high temperature to the fiber performance is eliminated, and the alumina ceramic matrix composite is strengthened, but the interface layer forms pores after sintering, so that when the material is used in a high temperature oxidizing environment, the material is first damaged at the interface, and the pores will make it The fiber and the matrix form a weak interface, and the fiber debonding and pull-out phenomenon occurs during the loading process of the composite material

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