Preparation method of silicon carbide powder

Abstract

The invention discloses a preparation method of a silicon carbide powder. The preparation method comprises the following steps: firstly, preparing reactants: according to certain proportions, preparing silicon powder, carbon powder, a nucleating agent and a catalyst, and thoroughly mixing the raw materials, wherein the silicon powder contains 10-50% of amorphous Si by mass; then, performing combustion synthesis: putting the prepared reactants into a combustion synthesis reaction device, vacuumizing the reaction device, inflating nitrogen, igniting the reactants through heating an electrified tungsten wire, and sustainably combusting the ignited reactants till complete reaction; finally, collecting and treating a product. According to the method provided by the invention, enlargement of equipment becomes possible through creative design, and synthesis of more than 100kg of nano or sub-micron silicon carbide powder in a single furnace is achieved at a relatively low temperature and a relatively low pressure; due to the preparation method, a combustion synthesis technology of silicon carbide can be indeed popularized for large-scale industrial production, and a brand-new and low-cost production technology is provided for producing high-quality ultrafine silicon carbide powder.

Description

Technical field [0001] The invention relates to the technical field of inorganic material preparation. More specifically, it relates to a method for preparing silicon carbide powder. Background technique [0002] As an important structural ceramic material, silicon carbide ceramic has excellent characteristics such as low density, high hardness, strong wear resistance, and outstanding high temperature strength. It has been widely used in bearings, mechanical seal components, rocket nozzles, etc. As the original material for the production of silicon carbide ceramic products, the commercial demand for silicon carbide powder is also increasing year by year. In particular, high-quality sub-micron and nano-level ultra-fine silicon carbide powders have the advantages of large specific surface area and high sintering activity, making them the first choice for preparing fine-grained high-strength silicon carbide ceramics. [0003] There are many methods for preparing silicon carbide pow...

AI Technical Summary

Problems solved by technology

Compared with other methods, the combustion synthesis method has the advantages of rapidity and low energy consumption. However, since combustion synthesis requires harsh reaction conditions such as high temperature and high pressure, it is difficult to enlarge the equipment for combustion synthesis, and the volume is generally small, resulting in single-furnace synthesis. The quantity is limited, generally no more than 5kg

In order to increase production, dozens or even hundreds of devices must be used. On the one hand, this results in high investment in equipment. On the other hand, it requires a large number of workers to operate, which also increases labor costs and increases safety risks. This is very unfavorable for large-scale production

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