Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Computer program reveals optimum microstructure for new materials

07.01.2003


These images show shapes that a computer program found as the optimum structure for a composite material that conducts both heat and electricity.



Technique could help bring efficiency of biology to man-made materials

A Princeton chemist has developed a general mathematical system for designing materials that perform two functions at once, even when the desired properties sometimes conflict with each other.

Salvatore Torquato and colleagues used computers to calculate the optimum structure for any material that is a composite of two substances with differing properties. The achievement is the first simple example of a mathematically rigorous method for optimizing the design of multifunctional composites, which are an increasingly common kind of material.



The approach could help bring to man-made materials the efficiency of design that characterizes so many biological materials. "Biological materials are inherently multifunctional," said Torquato. "They have evolved over millions of years to cope with a wide range of situations, so they perform a variety of functions well."

A tree, for example, has to support its weight and resist winds while transporting liquids up and down its length, said Torquato, who is a professor in the Princeton Materials Institute as well as the Department of Chemistry. "Until our work, however, there has been no clear and simple example that rigorously demonstrates the effect of competing property demands on composite microstructures."

In addition to its possible applications in materials science, the method may help biologists study natural materials, such as the walls of a cell, to understand why they are built as they are. "Using rigorous optimization techniques, we are now in a position to test some of the basic tenets of biology," Torquato said. "Are there elements of biology -- perhaps subsystems within an organism or cell -- that are optimized in any sense?"

Torquato and co-authors Sangil Hyun, a postdoctoral fellow, and Aleksandar Donev, a graduate student, described their findings in a paper published in the Dec. 23 edition of Physical Review Letters.

In their paper, the scientists demonstrated their approach by finding the ideal structure for a composite that is good at conducting both electricity and heat. Many materials already are good at both those tasks, but Torquato chose ones that are good at only one or the other. Running the scientists’ program, the computer arrived at surprisingly complex shapes as the optimum way in which the two materials should mix with each other at a microscopic scale.

The technique is general and could be used to optimize many properties, Torquato said. The technology already exists to make materials assemble themselves into finely tuned micro-scale patterns like the ones the scientists generated in their demonstration, Torquato said.

"I think it’s phenomenal work and it’s something that is very needed and timely," said Jeff Brinker, a senior scientist at Sandia National Laboratory and professor of chemical and nuclear engineering at the University of New Mexico. Brinker is preparing to collaborate with Torquato to test the idea in actual materials.

As fabrication techniques improve, materials scientists increasingly need such theoretical work to guide them, Brinker said. "How should we direct the self assembly? Sometimes it’s not very intuitive what the optimum structure should be."

The shapes produced by the computer are interesting in themselves, said Torquato. The best structure for simultaneous heat and electricity flow turned out to be a complex shape called a "bicontinuous triply periodic minimal surface," which Torquato recognized from other situations. A minimal surface is one that takes up the least amount of area for a given volume. A soap bubble is a common example of a minimal surface. Usually, this shape arises from a need to minimize surface tension. The researchers were surprised to see a minimal surface in their ideal conductor because neither of their stipulated properties have anything to do with surface tension.

Studying these non-intuitive shapes may offer insights into the relation between structure and function in both biological and man-made materials, Torquato said. "These results and the shapes we found suggest to me that there are incredibly rich opportunities that have not even been tapped into," he said.

Steven Schultz | EurekAlert!
Further information:
http://www.princeton.edu/

More articles from Materials Sciences:

nachricht Scientists develop low-cost energy-efficient materials
24.04.2019 | National University of Science and Technology MISIS

nachricht Modified 'white graphene' for eco-friendly energy
23.04.2019 | Tomsk Polytechnic University

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Energy-saving new LED phosphor

The human eye is particularly sensitive to green, but less sensitive to blue and red. Chemists led by Hubert Huppertz at the University of Innsbruck have now developed a new red phosphor whose light is well perceived by the eye. This increases the light yield of white LEDs by around one sixth, which can significantly improve the energy efficiency of lighting systems.

Light emitting diodes or LEDs are only able to produce light of a certain colour. However, white light can be created using different colour mixing processes.

Im Focus: Quantum gas turns supersolid

Researchers led by Francesca Ferlaino from the University of Innsbruck and the Austrian Academy of Sciences report in Physical Review X on the observation of supersolid behavior in dipolar quantum gases of erbium and dysprosium. In the dysprosium gas these properties are unprecedentedly long-lived. This sets the stage for future investigations into the nature of this exotic phase of matter.

Supersolidity is a paradoxical state where the matter is both crystallized and superfluid. Predicted 50 years ago, such a counter-intuitive phase, featuring...

Im Focus: Explosion on Jupiter-sized star 10 times more powerful than ever seen on our sun

A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter

  • Coolest and smallest star to produce a superflare found
  • Star is a tenth of the radius of our Sun
  • Researchers led by University of Warwick could only see...

Im Focus: Quantum simulation more stable than expected

A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.

Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...

Im Focus: Largest, fastest array of microscopic 'traffic cops' for optical communications

The technology could revolutionize how information travels through data centers and artificial intelligence networks

Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

First dust conference in the Central Asian part of the earth’s dust belt

15.04.2019 | Event News

Fraunhofer FHR at the IEEE Radar Conference 2019 in Boston, USA

09.04.2019 | Event News

 
Latest News

Proteins stand up to nerve cell regression

24.04.2019 | Life Sciences

New sensor detects rare metals used in smartphones

24.04.2019 | Life Sciences

Controlling instabilities gives closer look at chemistry from hypersonic vehicles

24.04.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>