Surface microporous SiC ceramic material and preparation method thereof

Abstract

The invention discloses a surface microporous SiC ceramic material, which consists of main raw materials, polycarbosilane and carboxymethyl cellulose, wherein the main raw materials consist of the following components in percentage by weight: 85 to 90 percent of silicon carbide powder and 10 to 15 percent of yttrium aluminum garnet; the polycarbosilane is 5 to 10 percent of the total weight of the main raw materials; and the carboxymethyl cellulose is 2 to 8 percent of the total weight of the main raw materials. Meanwhile, the invention discloses a method for preparing the surface microporousSiC ceramic material, which comprises the following steps of: uniformly mixing the silicon carbide powder, the yttrium aluminum garnet and the polycarbosilane, and adding aqueous solution of the carboxymethyl cellulose and performing ball-milling mixing; drying the obtained size; and molding the obtained powder and performing vacuum sintering at high temperature so as to prepare the surface microporous SiC ceramic material. The surface microporous SiC ceramic material keeps high strength, high hardness, abrasion resistance, corrosion resistance and oxidation resistance, the self-lubricating property of the material is improved, and a cross section can be prevented from being bonded. Therefore, the service life of the material is prolonged.

Description

technical field [0001] The invention relates to a surface microporous SiC ceramic material and a preparation method thereof. Background technique [0002] Ceramic materials are widely used in national defense, machinery, chemical industry, metallurgy, electronics and other fields. In recent years, industrially developed countries such as Britain, the United States, Germany, France, and Japan have widely used structural ceramics in the structural parts of aviation, aerospace and high-precision machinery, and have achieved considerable economic and social benefits. Among many engineering ceramic materials, silicon carbide (SiC) ceramics have high strength, high hardness, good wear resistance, corrosion resistance, strong oxidation resistance, high thermal conductivity, good high temperature stability, small thermal expansion coefficient, and heat resistance. It has become the most promising high-temperature structural ceramics due to its excellent properties such as strong sh...

AI Technical Summary

Problems solved by technology

Although the hardness of silicon carbide ceramics has been improved, some silicon carbide ceramic mechanical parts (such as silicon carbide seals) still have the following problems during use: 1), some silicon carbide ceramic mechanical parts (such as silicon carbide seals) When hard-to-hard seals are rubbed, the working surfaces at both ends are easily bonded, which increases the friction coefficient and shortens the service life

2) The debris generated during friction cannot be removed in time, which will accelerate the wear of mechanical parts, thus affecting the service life of seals

The above method has the following disadvantages: the cross-linked pores formed by the decomposition of the cross-linking agent at high temperature have different sizes, irregular shapes, and uneven distribution, and the product is prone to cracking during the sintering process, which affects the yield of the product