Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > MIT: A new approach to engineering for extreme environments --Scientist creates model to design radiation-resistant materials

Abstract:
Composite materials such as fiberglass, which take on a mix of properties of their constituent compounds, have been around for decades. Now, an MIT materials scientist is taking composites to the nanoscale, where entirely new properties, not found in any of the original compounds, can emerge.

MIT: A new approach to engineering for extreme environments --Scientist creates model to design radiation-resistant materials

Cambridge, MA | Posted on June 24th, 2009

Michael Demkowicz, an assistant professor in MIT's Department of Materials Science and Engineering, is part of a team based at Los Alamos National Laboratory that recently received a federal Energy Frontier Research Centers grant to develop nanocomposite materials that can endure high temperatures, radiation and extreme mechanical loading. The ultimate goal is to use these materials in energy applications including nuclear power, fuel cells, solar energy and carbon sequestration.

"All sectors of energy production need materials that can withstand extreme conditions," says Demkowicz, whose model offers a new approach to designing nanocomposites with desirable traits.

There are many models that can take a proposed material structure and predict how it will behave. However, such trial-and-error approaches still require repeated cycles of manufacture and testing and are "an extremely costly and time-consuming way to come up with a new material," says Demkowicz.

His model tackles what materials scientists call "the inverse problem" — specifying a desired set of properties and then predicting which structures will deliver them — and could dramatically speed up the design process.

Radiation resistance

Demkowicz' first target is radiation-resistant materials, which could improve the efficiency and safety of nuclear power plants.

Normally, when metals are exposed to radiation, high-energy particles such as neutrons bump into individual atoms and knock them out of their crystal lattice. Like billiard balls, the displaced atoms bump into neighboring atoms, spreading damage in the form of "vacancies" (holes where an atom is missing), and "interstitials" (an extra atom squeezed in where it shouldn't be). Clusters of these defects can make the material brittle and weak.

The key to making nanocomposite materials resistant to radiation damage lies in the interfaces between layers of different materials. As the layers become thinner, the interfaces play a more dominant role in the material properties because the ratio of interface area to the material's total volume becomes larger. These interfaces give rise to novel properties not found in the original materials.

In some nanocomposites, vacancies and interstitials can get trapped at interfaces, where they have a higher likelihood of meeting. When that happens, the extra atom fills in the hole and the crystal structure is restored. Under some conditions it can appear as if there was no radiation damage remaining at all, says Demkowicz.

Materials resistant to radiation damage could eventually be used to line nuclear reactors, a function now performed by stainless steel. That could extend the lifetime of nuclear reactors and allow them to operate under higher radiation doses. Whereas current reactors consume only about one percent of their fuel, these improved reactors could burn a higher percentage of nuclear fuel and leave behind less waste.

Demkowicz has used his model, which is based on reproducing the mechanical interactions of groups of atoms, to design a nanocomposite with interfaces that resist radiation. The material, described in Physical Review Letters last year, is a mix of copper and the metal niobium and could not be used in a nuclear reactor because it absorbs neutrons and becomes radioactive. However, now that he knows copper-niobium is resistant to radiation damage, Demkowicz can use his modeling techniques to look for other materials that share that property.

Once a promising candidate is identified, it takes several years of testing before a new material can be approved for use in a nuclear reactor, so it will likely be at least a decade before any of his potential new materials can be used, says Demkowicz.

In addition to Demkowicz, several other MIT researchers are involved in the new Energy Frontier Research Centers. MIT will host two of the centers — the Center for Excitonics, led by Associate Professor Marc Baldo, and the Solid-State Solar-thermal Energy Conversion Center, led by Professor Gang Chen.

Written by Anne Trafton, MIT News Office

####

For more information, please click here

Contacts:
Elizabeth A. Thomson
MIT News Office
E:
T: 617-258-5402

Copyright © MIT

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Harris & Harris Group Portfolio Company, AgBiome, Announces Partnership to Accelerate the Discovery of Next Generation Insect-Resistant Crops July 1st, 2015

Bruker Introduces Second-Generation Inspire Nanochemical Imaging Solution: Featuring Unique PeakForce IR and IR EasyAlign Technology July 1st, 2015

GLOBALFOUNDRIES Completes Acquisition of IBM Microelectronics Business: Transaction adds differentiating technologies, world-class technologists, and intellectual property July 1st, 2015

Samsung's New Graphene Technology Will Double Life Of Your Lithium-Ion Battery July 1st, 2015

Govt.-Legislation/Regulation/Funding/Policy

Proposed TSCA Nanomaterial Rule ‘Premature’, Says Former EPA Toxicologist July 1st, 2015

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Graphene flexes its electronic muscles: Rice-led researchers calculate electrical properties of carbon cones, other shapes June 30th, 2015

X-rays and electrons join forces to map catalytic reactions in real-time: New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions June 29th, 2015

Discoveries

Emergence of a 'devil's staircase' in a spin-valve system July 1st, 2015

Measurement of Tiny Amounts of Heavy Metals in Baby Food Samples July 1st, 2015

Chitosan coated, chemotherapy packed nanoparticles may target cancer stem cells June 30th, 2015

Graphene flexes its electronic muscles: Rice-led researchers calculate electrical properties of carbon cones, other shapes June 30th, 2015

Materials/Metamaterials

Proposed TSCA Nanomaterial Rule ‘Premature’, Says Former EPA Toxicologist July 1st, 2015

NEI Announces the Issuance of Multiple Patents on Self-Healing & Superhydrophobic Coatings June 30th, 2015

BASF and Fraunhofer IPMS-CNT jointly develop electronic materials June 30th, 2015

Green Chemistry Methods Used in Iran to Produce Zinc Oxide Nanoparticles June 27th, 2015

Announcements

Leti Announces Launch of First European Nanomedicine Characterisation Laboratory: Project Combines Expertise of 9 Partners in 8 Countries to Foster Nanomedicine Innovation and Facilitate Regulatory Approval July 1st, 2015

Bruker Introduces Second-Generation Inspire Nanochemical Imaging Solution: Featuring Unique PeakForce IR and IR EasyAlign Technology July 1st, 2015

GLOBALFOUNDRIES Completes Acquisition of IBM Microelectronics Business: Transaction adds differentiating technologies, world-class technologists, and intellectual property July 1st, 2015

Samsung's New Graphene Technology Will Double Life Of Your Lithium-Ion Battery July 1st, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project