Using a powerful electron microscope to view atomic-level details, Johns Hopkins researchers have discovered a "twinning" phenomenon in a nanocrystalline form of aluminum that was plastically deformed during lab experiments. The finding will help scientists better predict the mechanical behavior and reliability of new types of specially fabricated metals. The research results, an important advance in the understanding of metallic nanomaterials, were published in a recent issue of the journal Science.
At the microscopic level, most metals are made up of tiny crystallites, or grains. Through careful lab processing, however, scientists in recent years have begun to produced nanocrystalline forms of metals in which the individual grains are much smaller. These nanocrystalline forms are prized because they are much stronger and harder than their commercial-grade counterparts. Although they are costly to produce in large quantities, these nanomaterials can be used to make critical components for tiny machines called microelectromechanical systems, often referred to as MEMS, or even smaller nanoelectromechanical systems, NEMS.
But before they build devices with nanomaterials, engineers need a better idea of how the metals will behave. For example, under what conditions will they bend or break? To find out what happens to these new metals under stress at the atomic level, Johns Hopkins researchers, led by Mingwei Chen, conducted experiments on a thin film of nanocrystalline aluminum. Grains in this form of aluminum are 1,000th the size of the grains in commercial aluminum.
Phil Sneiderman | EurekAlert!
New thruster design increases efficiency for future spaceflight
16.08.2017 | American Institute of Physics
Tracking a solar eruption through the solar system
16.08.2017 | American Geophysical Union
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).
The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...
16.08.2017 | Event News
04.08.2017 | Event News
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16.08.2017 | Physics and Astronomy
16.08.2017 | Materials Sciences
16.08.2017 | Interdisciplinary Research