Preparation method of three-dimensional needling carbon/carborundum composite material bolt

Abstract

A preparation method of a three-dimensional needling carbon/carborundum composite material bolt adopts a three-dimensional needling fiber prefabrication body to prepare the composite material bolt. Pyrolytic carbon is deposited on the prefabrication body, carborundum substrates are deposited through chemical vapor infiltration (CVI), and a bolt bar blank and a bolt cap blank are obtained. The carborundum substrates of the bolt bar blank and the bolt cap blank which are obtained through machining are deposited through the CVI, a carborundum anti-oxidation coating is deposited through the CVI, and a three-dimensional needling C/SiC composite material bolt end product with the shear strength being 80-100MP is obtained. Compared with the prior art, the preparation method has the advantages that the number of times for getting into a furnace is reduced by 6-10, the densifying period is shorter, and the production cost is reduced. By means of a test of a CK6180-3000 numerically controlled lathe, the preparation method is small in diamond grinding wheel abrasion, hour norm for machining 30 bolt threads is reduced by about 10 hours, and as the abrasion of a grinding wheel is less, the working accuracy is improved, and industrialized batch production is achieved.

Description

technical field [0001] The invention relates to the technical field of preparation and processing of ceramic-based composite materials, in particular to a preparation process for three-dimensional needle-punched carbon / silicon carbide composite material bolts. Background technique [0002] The flight environment of aerospace vehicles is very harsh, and the maximum temperature on the nose cone, wing leading edge and fuselage flap surface can reach 1650°C, which requires the bolts and nuts used for the connection of structural parts of the thermal protection system to have excellent thermophysical and chemical properties and mechanical properties. performance. [0003] Standard bolt and nut materials for aerospace include graphite, carbon / carbon composites, and carbon / silicon carbide composites. Graphite has a series of advantages such as high temperature resistance, low density and good wear resistance, and carbon / carbon composite materials have a series of advantages such a...

AI Technical Summary

Problems solved by technology

[0005] In order to overcome the current situation that the existing 2D C / SiC composite bolt preparation technology is difficult to industrialized mass production due to the shortcomings of long production cycle, high cost and low mechanical properties of the bolt, the present invention provides a three-dimensional needle-punched carbon / silicon carbide composite The preparation process of material bolts uses three-dimensional needle-punched felt with a price of about 800 yuan / kg as the prefabricated body, and uses the CVI process to prepare three-dimensional needle-punched carbon / silicon carbide composite material bolts at room temperature by depositing a pyrolytic carbon interface layer on the prefabricated body. The tensile breaking strength is about 180-200MP, and the shear strength is about 80-100MP. The shear strength of the bolt is improved based on the original preparation method, the preparation cost is reduced, and the industrialized mass production of C / SiC composite bolts is realized.

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