A distinguished research professor of engineering physics, Sridharan and colleagues Yong Yang, Lizhen Tan and Kjetil Hildal spent summer 2008 preparing 500 smaller-than-a-sesame-seed samples for a unique study of how several traditional and cutting-edge materials fare in the harsh environment of a nuclear reactor.
“In terms of the number and diversity of samples being tested, this is one of the largest university-driven projects for studying the effects of radiation on materials in a national laboratory,” says Sridharan. “And, the samples are being irradiated in real-life conditions, as though they’d be in a nuclear reactor, which is a very unique opportunity for a university.”
The study, which includes about 20 different materials, could help researchers choose materials for the ultra-efficient nuclear reactors now under development. Unlike current reactors, these advanced reactors will operate at higher temperatures, pressures and radiation ranges, creating conditions today’s reactor materials can’t withstand.
“We’re trying to generate data that can be useful such that 10, 15, 20 years from now, the stage is set for somebody to build one of these advanced reactors,” says Todd Allen, a UW-Madison assistant professor of engineering physics.
Led by Sridharan and Heather MacLean, an Idaho National Laboratory (INL) engineer, the project is the first university-laboratory partnership at the recently created INL Advanced Test Reactor National Scientific User Facility.
In April 2007, the U.S. Department of Energy, which owns the test reactor, designated it as a national scientific user facility to support university, industry and national laboratory research of nuclear fuels and materials. In March 2008, UW-Madison’s Allen, a materials expert, also began serving as scientific director of the user facility.
The UW-Madison samples entered the INL test reactor in September 2008. Of the 500 samples, about half will be irradiated for one year, while the other half will remain in the test reactor until September 2010. Among the samples are steel, ceramics, amorphous alloys, and materials with a reinforced nanostructure for strength at high temperatures.
Depending on the material, each sample is receiving radiation at a constant temperature (ranging from 300 to 700 degrees Celsius). Many of the samples are under study at more than one temperature. INL engineers carefully arranged them in specially fabricated cylindrical capsules to ensure they receive even heat and radiation.
The samples are intentionally tiny; their small size enables researchers to analyze the effects of radiation via a technique called transmission electron microscopy. However, says Sridharan, the structural changes they will observe in the tiny disks are the same as those that would have occurred in “bulk” materials. “We are looking at the radiation response of a given material, which will be dictated by the material’s composition and structure, and not its size,” he says. “The project also includes tensile samples, which enable us to correlate these nanoscale structural changes to changes in bulk mechanical properties.”
Because the UW-Madison project is the first university project at the new INL user facility, Sridharan began planning with INL staff nine months earlier. “There are a lot of hurdles to be overcome before an experiment gets started,” he says.
For nearly six months, he and his colleagues participated in weekly teleconferences with INL staff. Not only did they prepare most of the samples, they also labeled each one and, among other data, provided INL staff the exact dimensions and composition of each sample. “Just telling them on the phone—or by e-mail—would not do it,” he says. “We had to actually reanalyze them and get them certified.”
The researchers’ experiences have laid the groundwork for the way in which other universities interact with INL. Since the UW-Madison experiment began, INL staff added three more university experiments to the reactor, and Sridharan has given lectures about how best to work with INL staff and prepare a research project for the user facility.
Now Sridharan and several research scientists and graduate students involved in the UW-Madison project are planning post-irradiation experiments for when the first batch of samples comes out of the reactor in September 2009. The project supplements the students’ on-campus research, which centers around using an ion beam to damage candidate reactor materials. “It gives them the chance to compare that with what happens in a real nuclear system,” says Allen, who splits his time between UW-Madison and INL and co-advises the students.
With INL staff, UW-Madison researchers will analyze their samples in Idaho—though Sridharan and colleagues at UW-Madison are developing analysis capabilities and hope to become a partner institution with the Advanced Test Reactor user facility. “We’re trying to establish this lab such that if INL has choke points—too many samples to analyze—they could send some of them here,” says Allen.
Because they lack the facilities and analysis capabilities, most universities can’t attempt research like as the UW-Madison project on their own. Ultimately, says Allen, the new partnerships enable universities to participate more fully in research with national laboratories, and in particular, the INL user facility. “Universities have not been able to define and lead major irradiation test programs as long as I have been involved in this field,” he says. “The UW experiment is the first in a number of projects where universities take the intellectual lead on a national level project.”
Collaborators on the UW-Madison project also include the University of Michigan, Penn State University, University of California, Oak Ridge National Laboratory, Los Alamos National Laboratory, Westinghouse, Gamma Engineering, and the Japan Atomic Energy Agency.
CONTACT: Kumar Sridharan, (608) 263-4789, firstname.lastname@example.org or Todd Allen, (608) 265-4083, email@example.com
Renee Meiller | Newswise Science News
Researchers printed graphene-like materials with inkjet
18.08.2017 | Aalto University
Superconductivity research reveals potential new state of matter
17.08.2017 | DOE/Los Alamos National Laboratory
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
18.08.2017 | Life Sciences
18.08.2017 | Physics and Astronomy
18.08.2017 | Materials Sciences