Silicon carbide fiber reinforced ceramic based structure wave absorption composite material and preparation method thereof

Abstract

The invention relates to a silicon carbide fiber reinforced ceramic based structure wave absorption composite material and a preparation method thereof. The silicon carbide fiber reinforced ceramic based structure wave absorption composite material is prepared from the following ingredients in percentage by volume: 30 to 40 percent of SiC fiber prefabricated bodies, 25 to 40 percent of SiC ceramicsubstrates and 20 to 45 percent of oxide ceramic substrates. Firstly, the SiC fiber prefabricated bodies are subjected to degumming treatment and drying; SiC is decomposed onto the SiC fiber prefabricated body subjected to the degumming treatment and drying; an SiCf/SiC wave absorption composite material is prepared; the obtained SiCf/SiC wave absorption composite material is soaked into silica sol, aluminum sol or zirconium sol; high-temperature treatment is performed; the silicon carbide fiber reinforced ceramic based structure wave absorption composite material is obtained. The SiCf/SiC ceramic with a certain porosity is firstly prepared; then, the materials are soaked into silica sol, aluminum sol or zirconium sol for hihg-temperature treatment; a compact double ceramic base compositematerial is obtained; the dielectric constant of the wave absorption composite material is effectively regulated and controlled; the good wave absorption effect is achieved.

Description

technical field [0001] The invention relates to the field of wave-absorbing materials, in particular to a silicon carbide fiber-reinforced ceramic matrix structure wave-absorbing composite material and a preparation method thereof. Background technique [0002] Among the high-temperature structural absorbing materials, continuous fiber reinforced ceramic matrix composites (CFRCMCs) have the most advantages. It has the advantages of high specific strength, high specific modulus, high toughness, etc. Through the design of the dielectric properties of the matrix and reinforcement, it can prepare high-temperature wave-absorbing materials with excellent performance. Continuous fiber-reinforced SiC-based composites rely on the high oxidation resistance of SiC fibers, the characteristics of adjustable electrical conductivity and excellent compatibility with SiC ceramic matrix, so SiC f / SiC composite material is the most potential high-temperature ceramic-based structure absorbing...

AI Technical Summary

Problems solved by technology

However, it is difficult for nano-absorbents to disperse uniformly in the matrix, which leads to poor controllability and uniformity of the dielectric properties of the absorbing composites, and also adversely affects the mechanical properties of the composites.

Preparation of SiC compared to PIP f / SiC composite material cycle is too long, the chemical vapor infiltration (CVI) method has a short preparation cycle, SiC f / SiC composites have strong mechanical properties, but due to the enrichment of free carbon in the prepared SiC matrix, the formed SiC f / SiC wave-absorbing composite material has a high complex dielectric constant and serious impedance mismatch, which cannot effectively absorb and lose electromagnetic waves.

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