Featured Research

from universities, journals, and other organizations

Metallic glass: A crystal at heart

Date:
June 16, 2011
Source:
DOE/SLAC National Accelerator Laboratory
Summary:
Glass, by definition, is amorphous. But when scientists squeezed tiny samples of a metallic glass under high pressure, they got a surprise: The atoms lined up in a regular pattern to form a single crystal. The discovery offers a new window into the structure and behavior of metallic glasses, which have been used for decades in products such as anti-theft tags and power transformers but are still poorly understood.

Scientists recently used a diamond anvil like this one to squeeze tiny samples of metallic glass. Under very high pressure, the samples switched from their amorphous, glassy state to form a single crystal -- the first time this behavior has been seen in a glass. The discovery. published in the June 17 issue of Science, could help scientists design better metallic glasses, which are widely used in power transformers, anti-theft tags and other products, and it may help explain why these materials are so tough.
Credit: Image courtesy Brad Plummer/SLAC.

Glass, by definition, is amorphous; its atoms lack order and are arranged every which way. But when scientists squeezed tiny samples of a metallic glass under high pressure, they got a surprise: The atoms lined up in a regular pattern to form a single crystal.

It's the first time researchers have glimpsed this hidden property in a glass. The discovery, reported June 17th in Science, offers a new window into the atomic structure and behavior of metallic glasses, which have been used for decades in products such as anti-theft tags and power transformers but are still poorly understood. The more scientists learn about the structure of these commercially important materials, the more effectively they can design new metallic glasses and tinker with old ones to improve their performance.

"Maybe a lot of glasses have this underlying structure, but we just didn't know how to look for it," said paper co-author Wendy Mao, a mineral physicist at the Department of Energy's (DOE) SLAC National Accelerator Laboratory and Stanford University.

Daniel Miracle, a metallurgist at the Air Force Research Laboratory in Ohio who was not involved in the research, called the discovery "a really, really neat, important finding." Not only will it help researchers design better metallic glasses, he said, but it may help explain why these materials can be so tough: If each piece of glass is a single crystal at heart, it doesn't have any of the weak spots at the boundaries between crystals where fractures and corrosion tend to start.

Unlike familiar window glass, metallic glasses are alloys made of metals -- in this case cerium and aluminum. They resist wear and corrosion and they have useful magnetic properties. If you took apart the plastic anti-theft tag on a DVD case, you'd find a thin piece of metallic glass that looks like aluminum foil. When you rent or buy a DVD, the checkout clerk rubs it across a pad to demagnetize the metallic glass so it won't trigger an alarm when you leave.

Scientists have been investigating metallic glasses for half a century, and in 1982 turned up the surprising discovery that these glasses do have some atomic structure, forming patterns over distances spanning just a few atoms. But no long-range patterns were apparent.

"The structure of glass is still mysterious. We know little about it, even though we use glass a lot," said Qiaoshi (Charles) Zeng of Zhejiang University in China, who led a research team of scientists from SLAC, Stanford, the Carnegie Institution of Washington, George Mason University and China's Jilin University. "And it's not easy investigating the structure of glass by traditional methods."

Zeng, Mao and their colleagues were not looking for order when they squeezed samples of the metallic glass between the tips of two diamonds at Argonne National Laboratory's Advanced Photon Source, applying 250,000 bars of pressure (250,000 times the pressure of Earth's atmosphere at sea level). They were simply doing a series of experiments on how materials behave in extreme conditions.

All the samples were taken from a centimeter-long, extremely thin ribbon of the metallic glass. Under intense pressure, all of the samples "devitrified," abruptly switching out of their glassy state to form a face-centered cubic crystal -- one whose atoms are arranged like ping-pong balls packed into a box.

What's more, all the atoms in the crystallized samples lined up in the same direction -- an indication, the researchers wrote, that this underlying structure ran throughout the whole ribbon of glass, and was put there when the glass formed.

Zeng, who will be joining Mao's group at Stanford in July, said the high-pressure technique may offer a new approach for making single-crystal materials from glasses. In addition, he said, it provides a unified understanding of the atomic structures of materials by directly linking the two most extreme examples: highly ordered single crystals and highly disorganized glass.

This work was supported in part by DOE's Office of Science through the Center for Energy Frontier Research in Extreme Environments, a DOE Energy Frontier Research Center led by the Carnegie Institute of Washington.


Story Source:

The above story is based on materials provided by DOE/SLAC National Accelerator Laboratory. Note: Materials may be edited for content and length.


Journal Reference:

  1. Qiaoshi Zeng, Hongwei Sheng, Yang Ding, Lin Wang, Wenge Yang, Jian-Zhong Jiang, Wendy L. Mao, and Ho-Kwang Mao. Long-Range Topological Order in Metallic Glass. Science, 2011; 332 (6036): 1404-1406 DOI: 10.1126/science.1200324

Cite This Page:

DOE/SLAC National Accelerator Laboratory. "Metallic glass: A crystal at heart." ScienceDaily. ScienceDaily, 16 June 2011. <www.sciencedaily.com/releases/2011/06/110616142724.htm>.
DOE/SLAC National Accelerator Laboratory. (2011, June 16). Metallic glass: A crystal at heart. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2011/06/110616142724.htm
DOE/SLAC National Accelerator Laboratory. "Metallic glass: A crystal at heart." ScienceDaily. www.sciencedaily.com/releases/2011/06/110616142724.htm (accessed July 23, 2014).

Share This




More Matter & Energy News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Government Approves East Coast Oil Exploration

Government Approves East Coast Oil Exploration

AP (July 18, 2014) The Obama administration approved the use of sonic cannons to discover deposits under the ocean floor by shooting sound waves 100 times louder than a jet engine through waters shared by endangered whales and turtles. (July 18) Video provided by AP
Powered by NewsLook.com
Sunken German U-Boat Clearly Visible For First Time

Sunken German U-Boat Clearly Visible For First Time

Newsy (July 18, 2014) The wreckage of the German submarine U-166 has become clearly visible for the first time since it was discovered in 2001. Video provided by Newsy
Powered by NewsLook.com
Obama: U.S. Must Have "smartest Airports, Best Power Grid"

Obama: U.S. Must Have "smartest Airports, Best Power Grid"

Reuters - US Online Video (July 17, 2014) President Barak Obama stopped by at a lunch counter in Delaware before making remarks about boosting the nation's infrastructure. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com
Crude Oil Prices Bounce Back After Falling Below $100 a Barrel

Crude Oil Prices Bounce Back After Falling Below $100 a Barrel

TheStreet (July 16, 2014) Oil Futures are bouncing back after tumbling below $100 a barrel for the first time since May yesterday. Jeff Grossman is the president of BRG Brokerage and trades at the NYMEX. Grossman tells TheStreet the Middle East is always a concern for oil traders. Oil prices were pushed down in recent weeks on Libya increasing its production. Supply disruptions in Iraq fading also contributed to prices falling. News from China's economic front showing a growth for the second quarter also calmed fears on its slowdown. Jeff Grossman talks to TheStreet's Susannah Lee on this and more on the Energy Department's Energy Information Administration (EIA) report. Video provided by TheStreet
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins