Scientists have developed a new, highly accurate method that analyzes metabolic biomarkers to assess whether a child is on the autism spectrum. Autism spectrum disorder affects about 1.5 percent of all children, but its exact cause remains unknown, and diagnosis requires a multidisciplinary ... more
Modelling how fracturing metallic glass releases energy at the atomic level
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.
"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.
- metallic glasses
- Rensselaer Polytech…
- molecular dynamics
- computational methods
A new study from Rensselaer Polytechnic Institute demonstrates how graphene foam can outperform leading commercial gas sensors in detecting potentially dangerous and explosive chemicals. The discovery opens the door for a new generation of gas sensors to be used by bomb squads, law enforcem ... more
A major breakthrough in remote wave sensing by a team of Rensselaer Polytechnic Institute researchers opens the way for detecting hidden explosives, chemical, biological agents and illegal drugs from a distance of 20 meters. The new, all-optical system, using terahertz (THz) wave technolog ... more
Many industrial buildings, including nuclear power plants and chemical plants, rely on ultrasound instruments that continually monitor the structural integrity of their systems without damaging or altering their features. One new technique draws on laser technology and candle soot to genera ... more
Monitoring and tracking biological threats or epidemics require the ability to carry out medical and laboratory tests in the field during a disaster or other austere situations. Expensive laboratory equipment is often unavailable in these settings, so inexpensive point-of-care technology is ... more
As a solution evaporates, the dissolved chemicals concentrate until they begin forming a crystal through a process called nucleation. Industries that use small crystals in pharmaceuticals, food and microelectronics are seeking to understanding this nucleation event. Scientists studying nucl ... more
- 1analytica 2020: New instruments for battery research
- 2Trends in analysis
- 3Finding the source of chemical reactions
- 4Gene scissors against incurable muscular disease
- 5Scientists learn more about the first hours of a lithium-ion battery's life
- 6First view of hydrogen at the metal-to-metal hydride interface
- 7Applied Photophysics board appoints Tim Flanagan as CEO
- 8Chemicals in the environment: A focus on mixtures
- 9Machine learning technique speeds up crystal structure determination
- 10The shape of water: What water molecules look like on the surface of materials