Fine granule Cr3C2 preparation method

Abstract

The invention provides a method for preparing Cr3C2 powder to meet the demand of producing superfine carbide alloy with the Fisher grain size Fsss being íœ 2ª–m, which comprises the following steps: (1) heating the non-corrosive steel vessel until the temperature being 300-350 Deg C, adding ammonium dichromate powder into vessel for disintegrating, stopping adding 2-4 hours later, cooling to room temperature and getting the Cr2O3 of 20-30 nm; (2) mixing C with Cr2O3 according to proportion (by weight) of C: Cr2O3 =0.32:0.35; (3) adding the mixed Cr2O3 and C into vacuum furnace for carbonization, the vacuum degree being ú“10Pa, rising the temperature to 1150-1200 Deg C and keeping it for 11-13 hours, venting H2 for cooling to room temperature; (4) ball grinding and breaking the got Cr2O3 and getting the Cr2O3 powder of thorough carbonization and the Fsss íœ2ª–m; the invention combines the chemical disintegrating and vacuum smelting, which is characterized by low carbonization temperature, short time and low cost.

Description

technical field [0001] The present invention relates to fine particle Cr 3 C 2 The preparation method, especially involves the combination of chemical decomposition and vacuum smelting to produce fine particle Cr 3 C 2 powder. Background technique [0002] Cr 3 C 2 As a grain growth inhibitor of cemented carbide, it has been widely used. With the development of the electronic industry, the requirements for ultra-fine cemented carbide are getting higher and higher. As the main phase of ultra-fine cemented carbide, the grain size of WC is generally Below 0.8 μm, the particle size requirements for cemented carbide additives are getting higher and higher. [0003] Preparation of Cr 3 C 2 The traditional method of powder is to add common Cr 2 o 3 It is mixed with solid carbon ball mill and carbonized by carbon tube furnace for secondary carbonization. This method has a high carbonization temperature, generally 1400~1500℃, and a long carbonization time. The powder partic...

AI Technical Summary

Problems solved by technology

[0003] Preparation of Cr 3 C 2 The traditional method of powder is to add common Cr 2 o 3 It is mixed with solid carbon ball mill and carbonized by carbon tube furnace for secondary carbonization. This method has a high carbonization temperature, generally 1400~1500℃, and a long carbonization time. The powder particle size is generally about 3~5μm, which is difficult to meet the requirements of ultrafine cemented carbide. Requirements for Inhibitors

[0004] At home and abroad, the preparation of fine particle Cr 3 C 2 There are few reports, and they mainly focus on gas-phase carbonization, using the carbonized Cr decomposed by organic matter 2 o 3 Preparation of Cr 3 C 2 , these methods all have the disadvantages of high cost and difficulty in industrialization