Nav: Home

Computer model predicts how fracturing metallic glass releases energy at the atomic level

July 19, 2018

WASHINGTON, D.C., July 19, 2018 -- Metallic glasses -- alloys lacking the crystalline structure normally found in metals -- are an exciting research target for tantalizing applications, including artificial joints and other medical implant devices. However, the difficulties associated with predicting how much energy these materials release when they fracture is slowing down development of metallic glass-based products.

Recently, a pair of researchers from Rensselaer Polytechnic Institute in Troy, New York, developed a new way of simulating to the atomic level how metallic glasses behave as they fracture. This new modeling technique could improve computer-aided materials design and help researchers determine the properties of metallic glasses. The duo reports their findings in the Journal of Applied Physics, from AIP Publishing.

"Until now, however, there has been no viable way of measuring a quality known as 'fracture energy,' one of the most important fracture properties of materials, in atomic-level simulations," said Yunfeng Shi, an author on the paper.

Fracture energy is a fundamental property of any material. It describes the total energy released -- per unit area -- of newly created fracture surfaces in a solid. "Knowing this value is important for understanding how a material will behave in extreme conditions and can better predict how any material will fail," said Binghui Deng, another author on the paper.

In principle, any alloy can be made into a metallic glass by controlling manufacturing conditions like the rate of cooling. To select the appropriate material for a particular application, researchers need to know how each alloy will perform under stress.

To understand how different alloys behave under different conditions, the researchers utilized a computational tool called molecular dynamics. This computer modeling method accounts for the force, position and velocity of every atom in a virtual system.

In addition, the calculations for the model are constantly updated with information about how the fractures spread throughout a sample. This type of heuristic computer learning can best approximate real-world conditions by accounting for random changes like fractures in a material.

Their model accounts for the complex interplay between the loss of stored elastic energy from an erupting fracture, and how much the newly created surface area of the crack compensates for that energy loss.

"Computer-aided materials design has played a significant role in manufacturing and it is destined to play far greater roles in the future," Shi said.
-end-
The article, "On measuring the fracture energy of model metallic glasses," is authored by Binghui Deng and Yunfeng Shi. The article appeared in the Journal of Applied Physics July 17, 2018, (DOI: 10.1063/1.5037352) and can be accessed at http://aip.scitation.org/doi/full/10.1063/1.5037352.

ABOUT THE JOURNAL

Journal of Applied Physics is an influential international journal publishing significant new experimental and theoretical results of applied physics research. See http://jap.aip.org.

American Institute of Physics

Related Metallic Glass Articles:

Nature: 3-D-printing of glass now possible
3-D-printing allows extremely small and complex structures to be made even in small series.
Atomic 're-packing' behind metallic glass mystery
A new method uncovers a four-decade mystery about metallic glass that could allow researchers to fine-tune its properties to develop new materials.
Argon is not the 'dope' for metallic hydrogen
Hydrogen is both the simplest and the most-abundant element in the universe, so studying it can teach scientists about the essence of matter.
Machine learning method accurately predicts metallic defects
For the first time, Berkeley Lab researchers have built and trained machine learning algorithms to predict defect behavior in certain intermetallic compounds with high accuracy.
Metallic hydrogen, once theory, becomes reality
Nearly a century after it was theorized, Harvard scientists have succeeded in creating metallic hydrogen.
From theory to reality: The creation of metallic hydrogen
For more than 80 years, it has been predicted that hydrogen will adopt metallic properties under certain conditions, and now researchers have successfully demonstrated this phenomenon.
Glass's off-kilter harmonies
The transport of heat in amorphous materials is largely determined by the behavior of phonons -- quasiparticles associated with the collective vibrations of atoms.  Researchers from Georgia Tech developed a new way to calculate the heat contribution of phonons using computer simulations.
Biggest and best diamonds formed in deep mantle metallic liquid
New findings explain how the world's biggest and most-valuable diamonds formed -- from metallic liquid deep inside Earth's mantle.
Towards better metallic glasses
Researchers from the University of Bristol have used state-of-the-art computer simulation to test a theory from the 1950s that when atoms organize themselves into 3-D pentagons they suppress crystallization.
Smashing metallic cubes toughens them up
Rice University scientists smash silver micro-cubes at near supersonic speeds to see how deforming their crystalline structures can make them both stronger and tougher.

Related Metallic Glass Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Setbacks
Failure can feel lonely and final. But can we learn from failure, even reframe it, to feel more like a temporary setback? This hour, TED speakers on changing a crushing defeat into a stepping stone. Guests include entrepreneur Leticia Gasca, psychology professor Alison Ledgerwood, astronomer Phil Plait, former professional athlete Charly Haversat, and UPS training manager Jon Bowers.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".