A kind of continuous firing method of boron-containing SIC fiber

Abstract

The invention discloses a method for continuous firing of boron-containing SiC fibers. In the method, SiC fibers are used as raw materials, and the raw materials are first subjected to surface activation treatment to obtain pretreated fibers with high reactivity on the surface; Soak in the solution of the compound and dry to obtain the intermediate fiber; finally, the intermediate fiber is fired at high temperature to obtain the boron-containing SiC fiber. The method provided by the invention can dynamically and quantitatively introduce boron into the sintering furnace to ensure that the concentration of the boron-containing atmosphere in the sintering furnace is relatively constant, and then react in situ with the highly active SiC fiber that has undergone surface activation treatment to realize the introduction of boron. The process is simple, the cost is low, and it is suitable for industrial production. The prepared boron-containing SiC fiber has excellent high temperature resistance, and has a good application prospect in aerospace, aviation and high-performance weaponry.

Description

technical field [0001] The invention relates to the technical field of ceramic fibers, in particular to a continuous firing method for boron-containing SiC fibers. Background technique [0002] Continuous SiC fiber has the advantages of low density, excellent mechanical properties and high temperature resistance, and good compatibility with ceramic matrix. It is a commonly used structural reinforcement for advanced composite materials and has been widely used in aerospace, aviation and high-performance weaponry. [0003] The precursor conversion method is the most successful method for preparing SiC fibers. It mainly includes the synthesis of polycarbosilane precursors, melt spinning, non-melting and high-temperature firing. The design and optimization of precursors and preparation routes can be adjusted. The composition and structure of the fiber, so as to prepare high-performance SiC fiber. The main components of SiC fibers prepared by the precursor method include SiC x ...

AI Technical Summary

Problems solved by technology

[0006] The invention provides a continuous firing method for boron-containing SiC fibers, which is used to overcome the cumbersome raw material synthesis steps in the prior art and the complex process of introducing boron without melting and the great environmental hazards; static and quantitative placement of boron oxide solids in the firing furnace will cause problems The gradient of boron oxide content in the preparation process decreases, which leads to the instability of the amount of boron introduced; the introduction of boron by vaporization has defects such as high cost, difficult maintenance and repeated use, etc., so that boron can be dynamically and quantitatively introduced into the firing furnace to ensure that the firing furnace contains The boron atmosphere concentration is relatively constant, and then reacts with the surface-treated highly active SiC fiber in situ to realize the introduction of boron. It has simple process, low cost, and is suitable for industrial production. The prepared boron-containing SiC fiber has excellent high temperature resistance. It has a good application prospect in aerospace, aviation and high-performance weaponry

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