Pyrophyllite for synthetizing diamonds

Abstract

The invention discloses pyrophyllite for synthetizing diamonds which is prepared from the following components in percentage by weight: 80% of pyrophyllite powder, 3 to 5% of bauxite powder, 2 to 3% of mica powder, 2 to 3% of wollastonite powder, 3 to 5% of diabase powder, and 7 to 7.5% of sodium silicate. In the aspect of the granularity of the pyrophyllite powder, 12 to 18 mesh coarse powder accounts for 30% of the total weight of the pyrophyllite powder, 18 to 60 mesh plain powder accounts for 30% of the total weight of the pyrophyllite powder; and fine powder with the granularity below 100 meshes accounts for 40% of the total weight of the pyrophyllite powder. The preparation method comprises the following steps of: 1. preparing the raw materials according to the weight percentages for standby; 2. putting the pyrophyllite powder in a blender mixer, adding the raw materials and evenly mixing; 3. adding the sodium silicate, and keeping mixing till the mixture is even; 4. adding finepowder in the pyrophyllite powder in the mixed materials obtained in the step 3 for standby; 5. weighing pyrophyllite mixed materials needed for making pyrophyllite hollow blocks; 6. putting the weight mixed materials in a pyrophyllite block mould to make the pyrophyllite hollow blocks; and 7. and calcinating the made pyrophyllite hollow blocks in a furnace. Since pyrophyllite powder is used for making synthetized pyrophyllite, the obtained pyrophyllite has good effect of sealing, transmitting pressure, heat insulation and insulation in the process of synthetizing diamonds.

Description

technical field [0001] The invention relates to a pressure transmission material used in a diamond synthesis process, which is pyrophyllite for diamond synthesis. Background technique [0002] At present, pyrophyllite is the sealing pressure transmission material used in the diamond synthesis process. The role of pyrophyllite is to seal, transmit pressure, heat and insulate the synthetic cavity under the high temperature and high pressure of synthetic diamond. Due to the continuous improvement of diamond synthesis technology, the temperature and pressure in the diamond synthesis chamber are relatively high, so that after the pyrophyllite block is subjected to high temperature and pressure, the inner layer with a higher temperature is prone to phase change, and a phase change layer is formed in the chamber. The volume shrinkage associated with layer change is likely to cause a large pressure loss and a decrease in thermal insulation performance. For this reason, pyrophyllit...

AI Technical Summary

Problems solved by technology

However, the shortcomings of this composite technology are: poor stability, prone to cracks, complicated manufacturing process, etc.