Method for preparing carbon pottery aircraft brake disc

Abstract

The invention discloses a method for preparing a carbon pottery aircraft brake disc. The method comprises the following steps: by taking a C / C composite material of which the density is 1.0-1.5g / cm<3>as a blank, performing PIP (precursor infiltration and pyrolysis) treatment, high temperature treatment and RMI (reaction siliconing process) on the blank in sequence so as to obtain a carbon potterycomposite material of which the density is 2.0-2.2g / cm<3>; and soaking the carbon pottery composite material into silica sol for multiple times in vacuum, performing drying till the weight gain rateof the carbon pottery composite material is 1-4%, and performing thermal treatment, so as to obtain the carbon pottery aircraft brake disc, wherein the RMI treatment comprises the following steps: putting the blank after high temperature treatment into a graphite mold with silicon powder and amorphous silicon carbide powder, and performing a siliconing reaction under a vacuum condition, wherein the amorphous silicon carbide powder is obtained by sintering a silicon carbide ceramic precursor at 800-1000 DEG C. The brake disc has stable friction performance, has adjustable friction coefficients,has a small friction amount, has no conspicuous vibration in the brake process, has a brake curve which is rectangular, stable without wash back, and is applicable to aircraft brake discs expected bybrake of high / low movement loading systems such as an airplane and a helicopter.

Description

technical field [0001] The invention belongs to the field of brake material development, and in particular relates to a preparation method of a carbon-ceramic aircraft brake disc. Background technique [0002] As a recognized high-performance braking material, carbon-ceramic composite materials have the advantages of high and stable friction coefficient in dry and wet conditions, excellent running-in and thermal conductivity, high service load, and strong environmental adaptability. [0003] At present, the preparation methods of carbon-ceramic friction materials mainly include precursor impregnation pyrolysis (PIP) and reactive silicon infiltration (RMI). The basis of these two preparation methods is the carbon-carbon composite material, and the distribution uniformity of the pyrolytic carbon matrix of the carbon-carbon composite material is difficult to control during the preparation process, and the higher the density, the larger the inhomogeneity gradient. The PIP proce...

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Problems solved by technology

The PIP process can well eliminate the inhomogeneity caused by the carbon-carbon material during the preparation process. The bonding ability of the silicon carbide generated by the cracking of the precursor to the carbon-carbon body or itself is weaker than that of reactive silicon infiltration, and will not damage the strength of the material. , and the braking performance is stable without vibration, but the silicon carbide prepared by the precursor impregnation and cracking process is nano-scale, and the final material cannot be dense in surface, its friction coefficient is low, and the wet state attenuation is large, so it is not suitable for high energy load. brake

[0004] At present, the reactive siliconizing process is mainly used for aircraft brakes. However, in the reactive siliconizing process, due to the consumption of some carbon, the density of the carbon-carbon green body is required to be high, and a large amount of liquid silicon is filled in the large pores in the green body. It cannot fully react with carbon, resulting in a high residual amount of silicon. The prepared carbon-ceramic friction material has a large difference in microstructure and composition between the inside and the surface. Stable, wet state attenuation is too large

And in the process of infiltration, liquid silicon and pyrolytic carbon or some carbon fibers form an excessively strong interface, resulting in damage to the strength of the material

In a word, there are still defects in the use of reactive siliconized brake discs in the braking field, such as high friction coefficient, easy to lock, large vibration, great damage to other parts of the brake system, and high price. At present, Only used on some military aircraft

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