Polycrystalline diamond catalyst and thermal treatment process thereof

Abstract

The invention discloses a polycrystalline diamond catalyst and a thermal treatment process thereof. The polycrystalline diamond catalyst comprises the following chemical components in percentage by weight: 3-4 percent of cobalt, 27-34 percent of iron, 27-31 percent of manganese, 18-22 percent of nickel, 13-17 percent of silicon and 3-4 percent of carbon. The catalyst is thermally treated for certain time at certain temperature to form a novel catalyst. The polycrystalline diamond catalyst and the thermal treatment process thereof have the beneficial effects that after the catalyst is thermally treated, the surface of the catalyst is roughened by oxidization, a grain structure of the catalyst is changed, and the synthesis contact range of the catalyst is widened; the catalyst treated by using the thermal treatment process has the advantages of wide synthesis pressure range, wide synthesis temperature range, high yield per unit, short time and controllability of the synthesis process when being used for synthesizing polycrystalline diamond; the synthesized polycrystalline diamond is irregularly shaped, has the rough surface and few impurities, is dark green, and is excellent in self-sharpening capacity and high in thermal stability.

Description

Technical field [0001] The invention relates to the field of artificial diamonds, in particular to a polycrystalline diamond catalyst and its heat treatment process. Background technique [0002] Synthetic diamond is converted from graphite under ultra-high pressure and high temperature conditions with the participation of catalyst metals. High-grade synthetic diamond is synthesized. Under ultra-high-pressure and high-temperature synthesis environment, nickel-manganese or nickel-cobalt catalysts are used. The current common catalyst is Ni70-Mn25-Go5, which converts graphite into single crystal diamond. Single crystal diamond has the defects of large magnetism and low strength, which can no longer meet the market demand. Polycrystalline diamond particles are composed of multiple sub-crystals with embedded structure and have high strength, which can better meet the needs of high-end markets at home and abroad. However, the current catalysts cannot make the diamond form a polycryst...

AI Technical Summary

Problems solved by technology

Single crystal diamond has the defects of high magnetism and low strength, which can no longer meet the market demand. Polycrystalline diamond particles are composed of multiple subcrystals with embedded structures, and have high strength, which can better meet the needs of high-end markets at home and abroad.

But current catalysts do not allow diamond to form a polycrystalline structure during growth