Continuous firing method of boron-containing SiC fiber

Abstract

The invention discloses a continuous firing method of boron-containing SiC fiber. According to the method, SiC fiber is taken as a raw material and is firstly subjected to surface activation treatment, and pretreated fiber with high reaction activity is obtained; the activated fiber is wetted in a solution of a boron-containing compound and dried, and an intermediate fiber is obtained; finally, the intermediate fiber is fired at the high temperature, and the boron-containing SiC fiber is obtained. By means of the provided method, boron can be introduced into a firing furnace in a dynamic quantitative manner, the concentration of boron-containing atmosphere in the firing furnace is kept relatively constant, the boron-containing compound and high-activity SiC fiber subjected to surface activation treatment are subjected to an in-situ reaction, introduction of boron is realized, and the method adopts a simple process and is low in cost and suitable for industrial production. The preparedboron-containing SiC fiber has excellent high-temperature resistance and has good application prospects in aerospace, aviation and high-performance weapons.

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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