Here at AETC, we are very proud to have designed, in close collaboration with our industry partners, a High Pressure High Temperature (HPHT) cultured diamond press and are currently in the process of installing it within our facilities. With this press, we now have the capability to apply both heat and pressure simultaneously to produce our own synthetic diamonds.
Our press, which includes a highly specialized mold for the high-pressure synthesis of diamonds, supplies an electrical current as well as resistive heat emanated from graphite elements into a particle bed composed of both graphite and a catalyst. The heat and electricity work in conjunction to create a pressure and temperature environment allowing for the formation of the diamonds. Our use of phase diagrams helps us bring the temperature and pressure to the exact level needed in the eutectic to turn our graphite into synthetic diamonds.
How it works
While in the press, the graphite transforms into a liquid form, and, after sixty seconds, the press is turned off, discontinuing the flow of electrical current and allowing the liquified graphite to cool. During this cooling process, the graphite begins to crystallize, forming the synthetic diamonds. This technology is favored as graphite does not cost a great deal, and diamonds are priced per carat; therefore, the synthetic graphite can create a value added applications upwards of thousands of dollars per pound.
While synthetic diamonds are already in use within the industry for drills and cutting bits, at AETC, we are looking for new ways in which to utilize the synthetic diamond. One of the methods includes using it as a high temperature semiconductor. Diamonds are known to have the highest thermal conductivity and are particularly essential when silicon-based semiconductors cannot withstand the temperatures often necessary to operate machinery and systems.
Many systems operate at elevated temperature levels and often lose efficiency when they reach the threshold of temperatures larger than 100 degrees Celsius. These systems cannot operate without an efficient thermal conductor, and we are creating efficient thermal conductors using our synthetic diamonds.
Graphite and Coal
With our extensive experience in graphite and coal, we are able to test many varieties of graphite and establish which produce the best synthetic diamonds. Certain graphites may cause explosions within the press, some create large diamonds, and others small diamond dust. With our knowledge, we can reduce the margin of error and find the best graphite(s), coal and carbon precursors to craft synthetic diamonds for value-added use. For instance, we have recently determined that graphitized coal from the Navajo tribe in Arizona successfully creates synthetic diamonds, and our research from 2017 shows that coal works quite well with our press. AETC is the first to talk to the Navajo tribe about turning their coal into diamonds; we are also speaking with several other tribe nations and showing them how to add value back into their suffering coal industries.