Powdered catalyst for synthesizing octahedral diamond

Abstract

The invention discloses a powdered catalyst for synthesizing octahedral diamond. The powdered catalyst comprises the following alloy components by weight percentage: 3 to 7% of Nb, 3 to 5% of Mn, 2 to 2.5% of Co, 0.1 to 1% of Si, 0.5 to 1% of B4C, 0.02% of V and the balance of Fe. The preparation method of the powdered catalyst comprises the following steps of: firstly, preparing the alloy components according to the weight percentage, melting the materials and preparing the prefabricate alloy ingots in the protection of inert gases; secondly, re-melting the prefabricate alloy ingots; and finally, grinding and atomizing the metal fluid into the metal powder at the high pressure gas of 3 to 4.5 MPa, granulating the powder into spherical particles and sieving the prepared powder catalyst. Compared with the prior art, the catalyst for synthesizing the octahedral diamond improves the yielding by about 40 percent and improves the crystal form regularity of the diamond by about 35%. The content of the synthesized octahedron reaches 80 to 87%. The powdered catalyst of the invention has the oxygen content of not more than 100 PPm with uniform chemical ingredients; the particle has good spherical degree and the granularity is negative 200 / positive 500; and the percentage of the granularity scale is 75 to 95%.

Description

technical field

[0001] The invention relates to a powder catalyst used for synthesizing diamond products, which is a powder catalyst for synthesizing octahedral diamond. Background technique

[0002] Catalyst is an essential raw material in the synthesis process of diamond, and different catalysts are used when synthesizing diamond to obtain different crystal forms. At present, the powder catalyst used in the process of synthesizing octahedral diamond generally uses 65-70% iron and 30-35% nickel as the main raw materials. Although this catalyst has certain advantages in the synthesis of other crystal diamonds, however, When synthesizing octahedral diamond, many problems are prone to occur: poor synthesis stability, low yield, poor crystal form, insufficient octahedron content, etc.; due to the above shortcomings, the synthesis cost of octahedral diamond is relatively high and cannot be scaled up. Production. Because octahedral diamond has the advantages of high sharpness, ...