Reagent for restraining nucleation in synthesizing diamond

Abstract

This invention discloses a catalyst for artificially synthesizing diamond. The catalyst is composed of one ore more of Zn, Pb, Bi, La, Cu, Ca, Sn, Li, B, P and S. The method for synthesizing diamond uses graphite as the raw material, and a Fe / Ni alloy (Fe:Ni is 70:30) as the catalyst. The content of the nucleation inhibitor is 0.1-5 wt. % of graphite, and that of the catalyst is 25-40 wt.% of graphite. The method comprises: (1) ball-milling the catalyst, the nucleation inhibitor and graphite for uniform mixing; (2) compacting by isopressing; (3) pulverizing, granulating, molding and sintering to obtain graphite rods that can be used to synthesize diamond. The method can reduce nucleus number, improve nucleus distribution uniformity, and reduce or avoid glomerocryst formation.

Description

technical field [0001] The invention belongs to the technical field of catalyst materials for artificially synthesized diamond, in particular to a synthesis of one or more elements containing zinc, lead, bismuth, lanthanum, copper, calcium, tin, lithium, boron, phosphorus, sulfur and other elements Diamond nucleation inhibitor. Background technique [0002] In the industrial production of artificial diamond, graphite is generally used as raw material, and alloy catalysts (such as alloys formed by Fe, Ni, Mn, Co, etc.) are added to convert graphite into diamond at high temperature and high pressure. Zheng Risheng et al. "Study on the Nucleation Conditions of Synthetic Diamond", Mining and Metallurgy Engineering, 1994 (04), the growth of synthetic diamond includes two processes: one is the formation of crystal nuclei, and carbon atoms form lattices due to the participation of metals under high temperature and high pressure conditions. change, resulting in diamond nucleation; ...