Method to reduce the oil pressure during HPHT diamond synthesis: FEM simulations and experiments

Abstract

Here, a new type of supercharged cell assembly is proposed that can effectively reduce the oil pressure during high-pressure, high-temperature (HPHT) diamond synthesis. Finite element simulations showed that the pressure at the center of the synthesis cell increased with the volume of the pressurization block, and the proportion of materials with high compressive strength in the cell determined the central pressure. The experimental results verified that, under the same conditions, the oil pressure decreased by 2.25 MPa for each 1 mm increase in the height of the pressurization block, and this was consistent with the FEM simulations. The results can be used to optimize the design of high-pressure synthesis cells to decrease the oil pressure during diamond synthesis and reduce experimental costs by prolonging the service life of WC-anvils.