Process for preparing nanometer WC (wolfram carbide) powder through vacuum aerogel carbonization process

Abstract

The invention relates to a process for preparing nanometer WC (wolfram carbide) powder through a vacuum aerogel carbonization process, which comprises the following steps of: after nanometer wolfram powder with an average grain size d50 being less than or equal to 30 nm is cut at a high speed through SAXS (small-angle X-ray scattering), agitating and drying with anhydrous alcohol solution of phenolic resin under the ultrasonic dispersion to prepare nanometer-coated wolfram powder with a phenolic resin jacket; carbonizing for 45-60 minutes at a low temperature of 980-1050 DEG C and under the vacuum condition of 1-10 Pa; and preparing the nanometer WC powder with an average grain size d50 being equal to 60.5 nm and a maximum grain size dmax being less than or equal to 100 nm (The BET (Brunaure, Emmet and Teller) specific surface area is more than or equal to 6.4 m<2> / g). In the nanometer WC powder, the content of combined carbon is 6.00-6.10 percent (mass fraction), and the content of free carbon is 0.01-0.50 percent (mass fraction). The process has the beneficial effects that the process achieves the level of completely practical and mass production and has wide promotion significance and practical value. As the process is brief and short and has less investment, the process is also suitable for the investment and the production of middle-sized and small-sized enterprises.

Description

technical field [0001] The invention belongs to the technical field of preparation of tungsten carbide powder for cemented carbide, and in particular provides an industrialized production technology for preparing nanometer WC powder by using a vacuum aerosol carbonization process. Background technique [0002] WC powder is the main raw material of cemented carbide. Cemented carbide has been widely used in almost all sectors of the national economy because of its excellent properties such as high hardness, high red hardness, extremely high compressive strength, high wear resistance and corrosion resistance. my country is a big producer of cemented carbide and has more than 60 years of production experience. my country's tungsten ore resources are very rich, the annual output of cemented carbide has exceeded 7600 tons, and the annual demand for WC powder is about 6000 tons. The progress of material science in recent years has revealed that when the particle size of WC powder...

AI Technical Summary

Problems solved by technology

However, when using PF in the above two patents, how many (quantitative) activated carbon elements can be provided by PF under different temperatures and different vacuum degrees, and under what atmosphere conditions and at what temperature the organic phenolic resin is softened and decomposed. , pyrolysis, carbonization, graphitization, and the characteristics and distribution of product carbon particles are not enough.

Therefore it is inevitable that the nano-WC powder contains too much free carbon or W 2 C heterophase, especially the latter patent, without using a high-speed shearing machine, it is difficult to ensure that the particle size of WC powder is less than 100nm (actually 150~280nm) due to the large number of "bridging" aggregates. See patent figure 1