Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Aging in irradiated materials: First predictive model of the microstructure of irradiated iron

19.01.2005


Researchers from the CEA’s Nuclear Energy Division have, for the first time, been able to make a quantitative prediction of the evolution of radiation-induced defects in a structural material. The results obtained for iron, using multi-scale simulation techniques based on the atomic scale, will help provide greater insight into material aging phenomena in existing nuclear power plants and may be applied to nuclear systems of the future. They are to be published in the "Nature Materials" journal on January 4, 2005.



The evolution kinetics of radiation-induced defects in a material has a direct impact on changes in its microstructure and consequently on its mechanical properties. This makes the quantitative prediction of this kinetics and the phenomena governing it a major challenge for the nuclear industry.

This challenge can now be taken up by intercoupling computer simulation techniques operating on different scales. This is what is meant by multi-scale simulation; the numerical results obtained on one time and space scale were taken and used as input data for modeling on the next higher scale:


- first of all, ab initio computer simulations rooted in quantum mechanics described the structure and migration of defects and defect clusters. These simulations, which call for considerable computing resources, were performed by drawing intensively on the capabilities of the CCRT (research and technology computing center) set up on the CEA’s Bruyères-le-Châtel site.

- the second stage consisted in taking these elementary properties and reconstructing, on the basis of a kinetic model , the evolution of defects and their effects on the macroscopic properties of an irradiated iron sample one micron (a thousandth of a millimeter) in size, over a period of about one hour.

The simulations were compared with indirect experimental measurements . The excellent agreement obtained demonstrates the realism of this multi-scale model, which highlights the role played by the hitherto unsuspected migration of small interstitial and vacancy clusters. They challenge the interpretation of several earlier experiments and simulations and open the way for the quantitative simulation of more complex irradiated materials such as industrial steels. They will be used in interpreting the mechanical behavior of the ferritic steels used as structural materials in existing nuclear fission plants, as well as those proposed for future fusion plants.

Anne-Gabrielle Dauba-Pantanacce | alfa
Further information:
http://www.cea.fr

More articles from Physics and Astronomy:

nachricht Artificial agent designs quantum experiments
19.01.2018 | Universität Innsbruck

nachricht Only an atom thick: Physicists succeed in measuring mechanical properties of 2D monolayer materials
17.01.2018 | Universität des Saarlandes

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

More genes are active in high-performance maize

19.01.2018 | Life Sciences

How plants see light

19.01.2018 | Life Sciences

Artificial agent designs quantum experiments

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>