Method of carbon nanotube for modifying polyacrylonitrile-based carbon fiber interface produced in China

Abstract

The invention provides a method of a carbon nanotube for modifying a polyacrylonitrile-based carbon fiber interface produced in China. The technology includes four parts: (1) surface treatment of thedomestic polyacrylonitrile-based carbon fiber: firstly treating and removing colloid on the surface of carbon fiber at the temperature of 600-800 DEG C and then using the mixed acid of nitric acid andsulfuric acid to remove the impurities on the surface of fiber; (2) preparation of domestic carbon fiber preform where the carbon nanotube grows in situ: firstly putting treated carbon fiber needle preform in the organic solution of catalyst precursor and then growing the carbon nanotube in situ in a chemical vapor deposition furnace; (3) densification of preform: adopting chemical vapor infiltration process to densify the preform and depositing the preform for 200-350h so that the density of the preform reaches 1.70-1.75g / cm<3>; and (4) high-temperature heat treatment: putting the material in a vacuum carbonization furnace, heating to the temperature of 2, 000-2, 300 DEG C at the heating rate of 30-50 DEG C / h under the protection of nitrogen, argon and other gases and preserving the heatfor 3-5h, and finally, the finished product is obtained.

Description

Technical field: [0001] The invention provides a method for modifying the interface of polyacrylonitrile-based carbon fibers produced in China by carbon nanotubes, and belongs to the technical field of carbon / carbon composite materials. Background technique: [0002] Carbon / carbon (C / C) composite materials have been successfully used in missile nose cones and rocket engine nozzles for strategic nuclear weapons due to their good ablation resistance, thermophysical properties, friction and wear properties and high temperature mechanical properties. Throat lining and aircraft brake discs and other aerospace fields. C / C composite materials are used as structural materials for high temperature and long-term use to manufacture hot-end parts of aero-engines. It is the current research and development direction of advanced countries in the world. There is no developed country in the world to study a new generation of high-power aeroengines. The C / C composite material is not considered a...

AI Technical Summary

Problems solved by technology

In order to improve its mechanical properties, on the one hand, high-performance carbon fibers are used, but in terms of performance, domestic polyacrylonitrile-based carbon fibers have low strength, poor uniformity and stability, and many hairs (the breakage rate is 6 times that of foreign products. ), with a single variety and high production costs, it can only be used on ablation-resistant functional composite materials (low requirements for strength) and some civilian products, which is far from meeting the needs of my country's development of national defense high-tech weapons, greatly limiting On the other hand, it is necessary to adopt optimized weaving technology and good composite technology. Even so, this requirement is still difficult to meet.

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