Brown School of Engineering Hosts NEW.Mech Workshop

The Brown University School of Engineering is hosting the 2012 New England Workshop on the Mechanics of Materials and Structures on November 3, 2012, at the Granoff Center.

The one-day workshop aims to bring together the New England Mechanics community with an interest in exploring new directions on the mechanics of materials and structures and sharing the latest advancements in the field. The workshop is free of charge, and is focused primarily around students (graduate and undergraduate) and postdocs. The previous two years have seen tremendous enthusiasm and excitement from the scientific community and Brown is excited to be this year’s host.

The workshop will consist of four plenary invited talks and a number of contributed short talks. There will also be a poster competition, and the workshop will include a new component, the “Gallery of Mechanics”. This event will include movies that display research in the New England mechanics community. There will be awards for the top three entries.

The workshop is being organized locally by Christian Franck and Shreyas Mandre, assistant professors of engineering at Brown.

For more information, please go to: http://www.brown.edu/conferences/new-england-mechanics-materials-structures/

Brown to host advanced materials conference

Brown University has organized a conference to explore the frontier of advanced materials. The all-day gathering on Thursday, March 29, 2012, features talks and discussions by leading innovators and scientists in industry, academia, and the federal government. The meeting stems from a call by President Obama for American companies to develop advanced materials at twice the speed as currently possible and at a fraction of the cost.

Cyrus Wadia
“The federal government cannot by itself ensure that America remains the leader in this important sector.” PROVIDENCE, R.I. [Brown University] — Last June, President Obama announced the Materials Genome Initiative, an ambitious effort to assist American companies to develop advanced materials at twice the speed as currently possible and at a fraction of the cost. The proposal stems in part from the startling losses in employment and technology that have beset the U.S. manufacturing sector and is intended to reposition America as a leader in producing advanced materials from safer, lighter vehicles to solar cells as cheap as paint. In a new funding request for next fiscal year, Obama seeks more than $100 million to continue the initiative.

Hoping to capitalize on the momentum, Brown University has organized a conference on March 29, 2012, to explore synergies and research opportunities in advanced materials. The all-day gathering features talks and discussions by leading innovators and scientists in industry, academia, and the federal government.

The meeting takes place on the Brown campus at the Salomon Center for Teaching, on the College Green. An agenda, list of speakers and other information is available online.

Cyrus Wadia, assistant director for clean energy and materials research and development in the White House Office of Science and Technology Policy, will give the plenary address. He will talk about how advanced materials are essential to economic security and human well-being.

“The Materials Genome Initiative will speed the discovery and development of many of those materials, and I will explain why the federal government cannot by itself ensure that America remains the leader in this important sector and why success will depend on a wide range of stakeholders and efforts, including regional efforts like those at Brown University,” Wadia said.

Other speakers and panelists will explore:

• new materials for automobiles, aerospace, energy conversion/storage, microelectronics and medical devices;
• emergent computational and experimental approaches;
• strategies for sharing, storing, and searching materials data;
• best practices for industry/university/government collaborations.

“Brown’s hosting of this meeting highlights the important role that the University can play in building strong research initiatives in this area,” said Clyde Briant, vice president for research. “The focus on the Materials Genome Initiative is an area where Brown already has great research strengths and one that should help us build partnerships with many other industries and universities.”

“Brown engineering’s unique interdisciplinary culture is ideally suited for producing new breakthroughs in advanced materials,” said Lawrence Larson, dean of engineering. “These breakthroughs often occur at the boundaries between traditional disciplines, like materials science, mechanical engineering, or electrical engineering. We look forward to developing exciting new collaboration opportunities that will result from this conference.”

The Materials Genome Initiative is connected to a larger call announced by Obama last summer to enlist industry, universities, and the federal government to invest in emerging technologies that will create manufacturing jobs and enhance U.S. competitiveness. Earlier this month, the president also asked for $1 billion to create a National Network for Manufacturing Innovation, to fund up to 15 regional hubs of manufacturing excellence.

“I’m calling for all of us to come together — private sector industry, universities, and the government — to spark a renaissance in American manufacturing and help our manufacturers develop the cutting-edge tools they need to compete with anyone in the world,” Obama said in a speech last summer. “With these key investments, we can ensure that the United States remains a nation that invents it here and manufactures it here and creates high-quality, good-paying jobs for American workers.”

The Materials Genome Initiative would direct funding to the Department of Energy, the Department of Defense, the National Science Foundation, and the National Institute of Standards and Technology. The initiative will fund computational tools, software, new methods for material characterization, and the development of open standards and databases that will make the process of discovery and development of advanced materials faster, less expensive, and more predictable.

Ancient Lamps, Earrings Yield Their Secrets Under Neutron Imaging

“Neutron imaging gives researchers new tools for exploring artifacts and ancient technology”

Brown University School of Engineering Professor Brian Sheldon is the co-principal investigator on an exciting colloborative project that also includes Brown's Joukowsky Institute for Archaeology

For the first time at Oak Ridge National Laboratory (ORNL), neutron images in three dimensions (3-D) have been taken of rare archaeological artifacts. Bronze and brass artifacts excavated at the ancient city of Petra, in present day Jordan, were recently imaged in 3-D using neutrons at the High Flux Isotope Reactor’s CG-1D neutron imaging instrument.

The neutron imaging technique gives eager archeologists and ancient historians significant, and otherwise wholly inaccessible, insight into the manufacturing and lives of cultures that once occupied settlements within the Roman Empire, Middle East, and Colonial-Period New England.  

The samples imaged in 3D in August came from the collections of the Joukowsky Institute for Archaeology and the Ancient World at Brown University. They include an elaborate hanging bronze oil lamp, a large Roman coin, and—most charmingly—a standing dog figure, which might have been either a religious dedication or perhaps a toy. Although their original provenance is unknown, they are all excellent examples of common metal finds from antiquity.

Principal investigator (PI) Krysta Ryzewski, an assistant professor of anthropology at Wayne State University, and her co-PI Brian W. Sheldon, professor of engineering at Brown University, were loaned the artifacts for study from professor Susan E. Alcock, director of Brown’s Joukowsky Institute. 

In earlier work, the team conducted two-dimensional imaging of copper alloy (bronze and brass) artifacts both from Petra and from Greene Farm, a colonial-period plantation in Rhode Island. The samples include artifacts from daily life: a clothing buckle, a knife, and some building hardware.

Top: photo of ancient Greek lamp. Bottom: neutron radiograph of the same lamp.

One circular object from Petra was so corroded that it was unidentifiable. But when it was imaged with neutrons, underneath was a piece of jewelry, probably an earring. Petra is most famous as a trading center in ancient times, connecting the Mediterranean world with places as far away as India and China. It was the capital of an independent kingdom of the Nabataeans, until the emperor Trajan incorporated it into the Roman Empire in the early second century A.D.

The earlier imaging and analysis resolved some questions of object identity and raised many new ones about the techniques and materials that crafts people in the past used to make these objects. “We can also examine certain objects (such as the knife or the bronze lamp) to look for trace residues of the oil once burned in the lamp or what the knife was used to cut,” says Ryzewski.

“I first learned of the developing neutron imaging instruments at Oak Ridge in my conversations with Hassina Bilheux (lead instrument scientist for CG-1D). At the time I was a postdoctoral fellow in archaeology and engineering at Brown. I attended a neutron imaging workshop at SNS in November 2008, and became the only archaeologist to be part of the VENUS instrument development team. Brian Sheldon at Brown also joined then. We have been collaborating on all of the experiments with Hassina at SNS and HFIR,” she says.

The neutron imaging beam line is a huge step forward for these scholars. “Archaeologists and scientists can obtain relatively little information about the manufacture of archaeomaterials, ancient objects, and the materials from which they are constructed from external surfaces alone,” says Ryzewski. “Very few historical accounts describe the construction of such objects and archaeomaterials, ancient bronzes, or ceramic vessels. The only source of information about how these objects were constructed comes from their material properties and composition.”

Archaeological objects are reviewed as unique cultural resources. Earlier analysis often entailed extracting a sample from such an object, which meant damage and sometimes even wholesale destruction of an artifact so it could be mounted effectively for analysis. Analysts’ necessarily conservative treatment of archaeomaterials left many questions unanswered.

Imaging archaeological objects comprehensively and systematically with neutrons only became possible with the development of the CG-1D prototype beam line. Neutron activation analysis and neutron imaging at Oak Ridge means scholars can now conduct detailed, nondestructive analysis of samples. “There currently exist a vast array of archaeological objects and research questions about ancient and historical technological development that can now be posed,” says Ryzewski. “The CG-1D beam line has offered us an invaluable alternative for performing nondestructive, noninvasive analysis.”

CG-1D data can reveal the raw materials used, the manufacturing techniques, the historical development of alloys and composite materials and the geological origins of ores and clay. On the cultural side, researchers can learn about the activities of ancient people’s daily lives that such objects served.

“Archaeologists can now begin to precisely reconstruct past networks and patterns of resource extraction, trade and exchange, environmental impacts of industrial activities on ancient landscapes, and the transmission of craft production traditions over time,” Ryzewski says. “These are some of the sorts of questions that our current research and experiments are designed to address.“

The 3-D neutron imaging and quantitative analysis occurs at an instrument that is a time-of-flight beam line, with a chopper for producing pulses of neutrons to take noninvasive images. Neutrons, rather than x-rays, do the work.

“Part of our early work was to test the parameters of the instrument and how we might need to adjust the instrumentation to suit the artifacts, which tend to vary in composition, size, and density,” Ryzewski says. 

“We anticipated that we would be able to see beneath the surface and find evidence of manufacturing steps (mold seams), impurities or other organic inclusions in the metals, residue from the objects’ use, and microstructural or compositional elements,” she says.

Their data are still being processed, but preliminary results from the bronze lamp suggest that they will be able to see and examine aspects of all of these areas of interest once the 3-D data are compiled. 

“Our work is still in its early stages. We hope to reexamine these objects in further rounds of testing in 2012. We will expand our sample base to other types of metal artifacts, perhaps some excavated from shipwrecks. We hope to examine ceramic artifacts as well, Ryzewski says.

More broadly, the scholars may be in a position to offer information to scientists who specialize in the conservation and stabilization of museum collections. Other findings may provide insights into materials behavior of interest to materials science. “Each round of experiments raises many more questions about the materials in the object and about the instrumentation itself,” Ryzewski says.

This fall the researchers will return to HFIR to image some of the bronze objects for Bragg-edge peaks in the materials. Collaborating with Ryzewski and Sheldon are Bilheux and Lakeisha Walker of SNS and Susan Herringer, a doctoral student in materials science engineering at Brown and the Joukowsky Institute.

The group will publish their results in both archaeological and neutron sciences academic publications. In addition, they will present their initial findings at the annual Society for American Archaeology meetings in Memphis in April 2012.

Courtesy of Oak Ridge National Laboratory/Written by Agatha Bardoel