SiC nanowire in-situ enhanced SiCf/SiC composite material and preparation method of SiC nanowire in-situ enhanced SiCf/SiC composite material

Abstract

The invention discloses a SiC nanowire in-situ enhanced SiCf / SiC composite material and a preparation method of the SiC nanowire in-situ enhanced SiCf / SiC composite material. The composite material is prepared from a SiC fiber prefabricated part, SiC nanowires and a SiC ceramic matrix, wherein the SiC nanowires grow on a fiber surface of the SiC fiber prefabricated part in situ; the SiC nanowires are mutually wound to form a net-shaped structure; the SiC ceramic matrix is arranged in a pore of the SiC fiber prefabricated part. The preparation method comprises the following steps: (1) carrying out surface chemical modification treatment; (2) loading a catalyst; (3) carrying out chemical vapor deposition; (4) impregnating a precursor and cracking. The SiC nanowire in-situ enhanced SiCf / SiC composite material provided by the invention has the advantages that the SiC nanowires are uniformly distributed and are combined with SiC fibers well, the toughness is good and the density is high and the like; the preparation method is simple in process, low in requirements on equipment, environmental-friendly, and good in process commonality; the introduction volume fraction of the SiC nanowires is high and is controllable.

Description

technical field [0001] The invention relates to the field of ceramic matrix composite materials, in particular to a SiC nanowire in-situ reinforced SiC f / SiC composite material and its preparation method. Background technique [0002] Continuous SiC fiber reinforced SiC matrix (SiC f / SiC) composites have excellent properties such as low density, high specific strength, high specific modulus, and low chemical activity. In addition, they also have high resistivity and low neutron radiation-induced activity. They are widely used in aerospace, nuclear fusion reactors, and high temperature applications. Structural absorbing materials and other fields have broad application prospects. [0003] However, SiC f / SiC composites are used in high-temperature structural components, and their mechanical properties need to be further improved. Especially in its fracture toughness, there is still a big gap compared with materials such as superalloys. SiC f The low fracture toughness...

AI Technical Summary

Problems solved by technology

However, there is a strong van der Waals force between nanomaterials, coupled with the huge specific surface area and high aspect ratio of one-dimensional nanomaterials, it is easy to form entanglement or agglomeration, greatly reducing its reinforcement effect, and it is also difficult in the Introducing a high volume fraction of one-dimensional nanomaterial reinforcements into composites

Therefore, the properties of composites prepared by directly adding nano-reinforcement are still not satisfactory

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