Made-To-Order Materials: Engineers Focus On the Nano to Create Strong, Lightweight Materials
2013 09 06
The lightweight skeletons of organisms such as sea sponges display a strength that far exceeds that of humanmade products constructed from similar materials.
Scientists have long suspected that the difference has to do with the hierarchical architecture of the biological materials -- the way the silica-based skeletons are built up from different structural elements, some of which are measured on the scale of billionths of meters, or nanometers. Now engineers at the California Institute of Technology (Caltech) have mimicked such a structure by creating nanostructured, hollow ceramic scaffolds, and have found that the small building blocks, or unit cells, do indeed display remarkable strength and resistance to failure despite being more than 85 percent air.
Three-dimensional, hollow titanium nitride nanotruss with tessellated octahedral geometry. Each unit cell is on the order of 10 microns, each strut length within the unit cell is about three to five microns, the diameter of each strut is less than one micron, and the thickness of titanium nitride is roughly 75 nanometers.
"Inspired, in part, by hard biological materials and by earlier work by Toby Schaedler and a team from HRL Laboratories, Caltech, and UC Irvine on the fabrication of extremely lightweight microtrusses, we designed architectures with building blocks that are less than five microns long, meaning that they are not resolvable by the human eye," says Julia R. Greer, professor of materials science and mechanics at Caltech. "Constructing these architectures out of materials with nanometer dimensions has enabled us to decouple the materials’ strength from their density and to fabricate so-called structural metamaterials which are very stiff yet extremely lightweight."
At the nanometer scale, solids have been shown to exhibit mechanical properties that differ substantially from those displayed by the same materials at larger scales. For example, Greer’s group has shown previously that at the nanoscale, some metals are about 50 times stronger than usual, and some amorphous materials become ductile rather than brittle. "We are capitalizing on these size effects and using them to make real, three-dimensional structures," Greer says.
Read the full article at: sciencedaily.com
Water Nanofilter ‘Could Cut Diarrhea-Related Deaths’
Researchers watch nanoparticles self-assemble for the very first time
Nano-Suit Protects Bugs From Space-Like Vacuums
Nanoparticles Are in Our Food, Clothing and Medicine -- And No One Knows for Sure How Dangerous They Might Be
Nanomaterial Can Stop a Speeding Bullet, Strengthen Soldiers’ Body Armor
Nanotechnology condoms could provide greater protection against HIV and Herpes
Britain: Nanoscale Energy Storage Material Under Development
Upsalite: Scientists make ’impossible material’... by accident
Quantum Computers Coming Soon? Metamaterials Used to Observe Photonic Spin
Supertough, Strong Nanofibers Developed
Latest News from our Front Page
Sand Pirates: ISIS Are America’s 21st Century Terrorist Privateers
2014 11 01
What is ISIS? If you believe govt and corporate propaganda, you still think that ISIS is a grassroots Islamic ideological movement ¨C and with no connection to intelligence agencies like America¡¯s CIA, Britain¡¯s MI6, Turkish (NATO) intelligence, Saudi intelligence, Israeli intelligence, or Pakistan¡¯s ISI.
The reality of ISIS is something altogether different¡
On closer inspection, these marauding paramilitary ISIS gangs are nothing ...
Ancient Stone Circles in Mideast Baffle Archaeologists
2014 11 01
Huge stone circles in the Middle East have been imaged from above, revealing details of structures that have been shrouded in mystery for decades.
The Big Circle called J1 is about 390 meters (1,280 feet) in diameter, with an open area created by bulldozing in its interior.
Credit: David L. Kennedy, copyright is retained by the Aerial Photographic Archive for Archaeology ...
Sweden Recognizes Palestinian State; Israel Upset
2014 10 31
Sweden on Thursday became the biggest Western European country to recognize a Palestinian state, prompting a strong protest from Israel, which swiftly withdrew its ambassador from Stockholm.
The move by Sweden’s new left-leaning government reflects growing international impatience with Israel’s nearly half-century control of the West Bank, east Jerusalem and its blockade of the Gaza Strip. It also comes during increased ...
Fed-Backed Study: How to Brainwash Public into Fearing “Climate Change” Like Ebola
2014 10 31
$84K study seeks ways to make public fear "climate change and overpopulation"
The National Science Foundation is funding a study to determine how to brainwash the public into fearing “climate change and overpopulation” as if they were Ebola.
The NSF awarded an $84,000 grant to researchers at the State University of New York at Buffalo yesterday to figure out how to make ...
Brain decoder can eavesdrop on your inner voice
2014 10 31
As you read this, your neurons are firing – that brain activity can now be decoded to reveal the silent words in your head
TALKING to yourself used to be a strictly private pastime. That’s no longer the case – researchers have eavesdropped on our internal monologue for the first time. The achievement is a step towards helping people who cannot ...
|More News » |