Fastener using carbon/carbon/silicon carbide composite material and preparation method of fastener

Abstract

The invention discloses a fastener using carbon / carbon / silicon carbide composite material, with a simple production process and resistance to erosion of silicon vapor, and a preparation method of the fastener. The preparation method of the fastener is characterized by comprising the steps of carrying out the chemical vapor infiltration on the carbon fibre preform of the fastener to to densify pyrolytic carbon and silicon carbide alternatively or perform caballing to the pyrolytic carbon and the silicon carbide, mechanically machining, and purifying to obtain the product. The density of the fastener is between 1.3g / cm<3> and 2.5g / cm<3>; the flexural strength of the fastener is more than or equal to 300MPa; and the fracture toughness of the fastener is more than or equal to 15MPa.m<l / 2>. According to the fastener and the preparation method provided by the invention, the erosion of the silicon vapor on the core carbon fibre of the carbon / carbon / silicon carbide composite material can be effectively inhibited. The flexural strength of the prepared carbon / carbon / silicon carbide composite material is more than 300MPa and is 2-5 times of that of the carbon / carbon composite material; the fracture toughness of the carbon / carbon / silicon carbide composite material is more than or equal to 15MPa.m<l / 2>; the resistance of the carbon / carbon / silicon carbide composite material to the erosion of the silicon vapour is increased by 5-10 times compared with that of the carbon / carbon composite material; the service life of the fastener is greatly prolonged; and meanwhile, the higher strength of the fastener is beneficial to the improvement of the safety of the thermal field.

Description

technical field [0001] The invention relates to a hot field part for a high-temperature furnace and a preparation method, in particular to a carbon / carbon / silicon carbide composite fastener and a preparation method. Background technique [0002] Carbon / carbon composite material is one of the advanced composite materials widely used at present. It is a composite material formed by carbon fiber or various carbon fabrics to reinforce the carbon matrix. It has low density, high specific strength, wear resistance, high temperature resistance, and thermal expansion. Excellent performance such as small coefficient. The material is usually made of carbon fiber mesh tire and mesh tire, or carbon cloth and carbon cloth, or mesh tire and carbon cloth are composited into a carbon fiber prefabricated body by alternately stacking needle punching, and then the prefabricated body is put into a chemical gas phase reaction furnace. In the process, the preform is densified by chemical vapor p...

AI Technical Summary

Problems solved by technology

The literature points out that it is difficult to prepare high-density C / SiC or C / C-SiC composite materials by using a single CVI method, but it is possible to prepare high-density C / SiC or C / C-SiC composite materials by using a single PIP method or CVI+PIP method. For C-SiC composite materials, however, a certain amount of Si will remain in the PIP process, and the free Si will inevitably react with the carbon fibers, causing damage to the carbon fibers in the reinforcing phase, resulting in a decrease in the toughening and reinforcing effect of the carbon fibers, thereby improving the overall performance of the material. Decrease, especially the substantial reduction in mechanical strength, leading to catastrophic fracture of the material

At the same time, its process is complex and requires repeated dipping

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