To make super-durable and strong details it is necessary to use so-called diamond composites, i.e. materials (matrixes) with incorporated tiny diamonds. The matrix is to be durable, strong, wear-proof as well as monolithic by structure ensuring chemical interaction with diamonds. To avoid internal tension this matrix must have physical characteristics close to diamond ones. In other case the detail will collapse under load.
Carbide materials fit all these requirements because they are strong, wear-proof, thermostable and with high thermal conductivity. High thermal conductivity prevents the detail cracking at a temperature drop (as a glass can crack when filling with boiling water). It is impossible to make such materials by sintering diamonds with silicon carbide, because the required temperatures are so high that diamond just will turn into graphite. The sintering diamond grains with carbide at lower temperature and high pressure (about 8.5 GPa) is a rather expensive process and it can be applied only for manufacturing small details of a simple shape.
The scientists from the Saint-Petersburg-based Central Research Institute of Materials and their colleagues from the Royal Institute of Technology (Stockholm) have invented a new method. They have proposed to press half-finished details (blanks) from the powder made of micron-sized diamonds. Then they heated the details in a vacuum oven and saturated them with liquid silicon. During this procedure the diamond surface turns into graphite-like carbon which interacts with liquid silicon. As a result the finished detail represents a monolith of the required shape which consists from small diamonds soldered one with another by silicon carbide, and silicon itself.
Olga Maksimenko | Informnauka
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16.11.2017 | Karlsruher Institut für Technologie (KIT)
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
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Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
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The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...
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15.11.2017 | Event News
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17.11.2017 | Physics and Astronomy
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17.11.2017 | Studies and Analyses