Preparation method of compact C/C composite material

Abstract

The invention discloses a preparation method of a compact C / C composite material. The method includes: firstly preparing a 3D or 2.5D braided carbon fiber preform; then putting the preform into a vacuum chemical vapor deposition furnace, introducing methane and hydrogen, letting pyrolytic carbon produced by methane decomposition infiltrate the preform by chemical vapor infiltration to realize compaction of carbon fiber filaments within the preform, thus turning the preform into a C / C composite material skeleton; then infiltrating the obtained C / C composite material skeleton with a thermosetting resin solution by precursor infiltration and pyrolysis method, and conducting high temperature pyrolysis in a vacuum furnace to obtain a glass carbon matrix; and finally cycling the step (3) repeatedly, and stopping the operation when the weight gain rate of the material is lower than 1%, and finally conducting pyrolysis to obtain pyrolytic glass carbon filled among fiber bundles, thus realizing compaction of fiber bundles, and obtaining the compact C / C composite material. The material has the advantages of high density, low porosity, high specific strength, specific modulus, and good toughness, high compactness, wear resistance and long service life.

Description

technical field [0001] The invention relates to C / C composite materials, in particular to a method for preparing dense C / C composite materials, and belongs to the field of materials. Background technique [0002] Carbon / carbon composite material is a new type of high-temperature material with unique performance developed in the 1960s. It combines the excellent mechanical properties of fiber-reinforced composite materials and the excellent high-temperature performance of carbonaceous materials, and has high specific strength and specific modulus. It has a series of excellent properties such as good toughness, excellent strength retention at high temperature, creep resistance and thermal shock resistance. It is currently known as the most ideal high-temperature structural material under an inert atmosphere. Under certain conditions, carbon / carbon composite materials can be obtained by combining pyrolytic carbon with carbon fiber, and the chemical vapor infiltration (C VI) pro...

AI Technical Summary

Problems solved by technology

If only the CVI process is used, due to the diffusion and penetration of gaseous molecules, the densification between the fiber filaments can be achieved, but the fiber bundles cannot be densified due to the "bottleneck effect"; if only the PIP process is used, due to the high viscosity of the resin solution, It is easy to penetrate into the fiber bundles to achieve denseness between the fiber bundles, but it is difficult to penetrate into the fiber filaments, so that the gaps between the fiber filaments cannot be filled

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