Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Large Diamonds Made From Gas Are Hardest Yet

26.02.2004

Producing a material that is harder than natural diamond has been a goal of materials science for decades. Now a group headed by scientists at the Carnegie Institution’s Geophysical Laboratory in Washington, D.C., has produced gemsized diamonds that are harder than any other crystals, available at a rate that is up to 100 times faster than other methods used to date. The process opens up an entirely new way of producing diamond crystals for electronics, cutting tools and other industrial applications.

"This is a great example of fundamental research that will not only give us a better tool to duplicate conditions in the core of the Earth, but will stimulate many other scientific, technical and economic advances," said geologist James Whitcomb of the National Science Foundation (NSF)’s division of earth sciences, which funded the research.

"We believe these results are major breakthroughs in our field," said Chih-shiue Yan, lead author of the study published in the Feb. 20, online Physica Status Solidi. "Not only were the diamonds so hard they broke the measuring equipment, we were able to grow gem-sized crystals in about a day."

The researchers developed a special high-growth rate chemical vapor deposition (CVD) process to grow crystals. They then subjected the crystals to high-pressure, high-temperature treatment to further harden the material. In the CVD process, hydrogen gases and methane gases are bombarded with charged particles, or plasma, in a chamber. The plasma prompts a complex chemical reaction that results in a "carbon rain" that falls on a seed crystal in the chamber. Once on the seed, the carbon atoms arrange themselves in the same crystalline structure as the seed. This method has been used to grow diamond crystals up to 10 millimeters across and up to 4.5 millimeters thick.

CVD-produced crystals produced very tough. "We noticed this when we tried to polish them into brilliant cuts," said Yan. "They were much harder to polish than conventional diamond crystals produced at high pressure and high temperature." The researchers then subjected the tough CVD crystals to high-temperature and high-pressure conditions. The diamonds were heated to 2000° C and put under pressures of 50,000 to 70,000 times atmospheric pressure for 10 minutes. This final process resulted in the ultra -hard material, which was at least 50 percent harder than conventional diamonds.

The research was also supported by the U.S. Department of Energy, the National Nuclear Security Agency, through the Carnegie/ DOE Alliances Center, and the W. M. Keck Foundation. It was conducted in collaboration with researchers at the Phoenix Crystal Corporation and Los Alamos National Laboratory.

Cheryl Dybas | NSF
Further information:
http://www.nsf.gov
http://www.ciw.edu/

More articles from Physics and Astronomy:

nachricht Study offers new theoretical approach to describing non-equilibrium phase transitions
27.04.2017 | DOE/Argonne National Laboratory

nachricht SwRI-led team discovers lull in Mars' giant impact history
26.04.2017 | Southwest Research Institute

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>