Login to account Create an account  


  • 2 Vote(s) - 5 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Diamonds manufacturing without high pressures
#1
This is another thread of "super narrow" interest.  But I thought I'd share it, just in case anyone is like me in finding these kinds of developments significant.

Many people are aware of diamonds, most know that in nature it takes incredible temperatures, and physical compression to make diamond crystals grow... which is why in the past diamonds were a considerably rare thing to have.   Eventually, technologies and industry were able to reproduce the conditions (in a manner of speaking) and actually synthesize diamonds.
 

Natural diamonds form over billions of years in the Earth’s upper mantle at temperatures of between 900 and 1400 °C and pressures of 5–6 gigapascals (GPa). For the most part, the manufacturing processes used to make most synthetic diamonds mimic these conditions. In the 1950s, for example, scientists at General Electric in the US developed a way to synthesize diamonds in the laboratory using molten iron sulphide at around 7 GPa and 1600 °C. Although other researchers have since refined this technique (and developed an alternative known as chemical vapour deposition for making high-quality diamonds), diamond manufacturing largely still depends on liquid metals at high pressures and temperatures (HPHT).


But now a new process has 'accidentally' yielded diamonds at one atmosphere, but the high temperatures are still necessary...
 

A team led by Rodney Ruoff has now turned this convention on its head by making a polycrystalline diamond film using liquid metal at just 1 atmosphere of pressure and 1025 °C. When Ruoff and colleagues exposed a liquid alloy of gallium, iron, silicon and nickel to a mix of methane and hydrogen, they observed diamond growing in the subsurface of the liquid metal.


From PhysicsWorld.com: Synthetic diamonds grow in liquid metal at ambient pressure

Then there's the 'bonus' benefit that this process does not require a "seed crystal' as the current processes do.

With the potential growth of quantum computing, the ability to scale this process may make it a lot easier for the new tech to proliferate... assuming commerce doesn't strangle it to death.
Reply
#2
I found a later article from ZME Science.com: Scientists make diamonds from scratch in only 15 minutes
Subtitled: t takes over a billion years of high pressure cooking deep inside the Earth's mantle to make diamonds. But this synthetic variety took just a quarter of an hour to make.

Which highlights the speed at which the diamonds are produced.

Of course, in 15 minutes all you are ever going to get are tiny (microscopic) diamonds... so the need to scale this new process up is also highlighted.
 

There’s a catch, however. While the new method boasts incredible speed and simplicity, it comes at the cost of size. The diamonds produced are microscopic — too tiny to grace your finger or adorn a necklace. But there’s a silver lining. The low-pressure environment used in this technique has scientists optimistic about scaling up production. If they can figure out how to make these diamonds grow to a usable size, this could be a game changer for the industry.


I suppose the author was referring tot he jewelry industry.... diamonds are useful for other things (like quantum devices), you know.
Reply