Multiple activation treatment refers to processes such as double or triple multiple activation performed on the test core blank containing catalyst powder. First, thermal static degassing activation is conducted on the core blank within a specific temperature range and at a vacuum degree of 10−3 mmHg, ensuring that the powder core blank does not oxidize or sinter. After the degassing activation is completed, a second step of activation treatment is carried out under the protection of inert gas.

Improving appearance and crystal shape: This treatment effectively removes oxygen and other impurities from the core blank to an extremely low level, making the synthesized diamond beautiful in color and highly complete in crystal shape (mainly hexahedrons and octahedrons).

Increasing the proportion of coarse grains: It can significantly increase the percentage of coarse-grained diamonds. The result of the triple multiple activation treatment is particularly outstanding: the main peak of the particle size is concentrated at 45/50 mesh (accounting for 41.98%), and the secondary peak is at 40/45 mesh, with the sum of these two values exceeding 70%.

Comprehensively enhancing mechanical properties: This process can significantly improve the static pressure strength and impact toughness of the diamond. It also improves the thermal impact toughness, resulting in a much smaller decrease in the toughness index of the diamond at high temperatures.