College of Engineering News • Iowa State University

New DOD projects support new instruments, with eye on new materials

Two Iowa State University engineering faculty members have received awards from the Department of Defense under the Defense University Research Instrumentation Program (DURIP).

The Army Research Office, an element of the U.S. Army Combat Capabilities Development Command’s Army Research Laboratory, represents the Army’s portion of the DURIP program.

These highly-competitive awards support the development of cutting-edge equipment and instrumentation, accelerating basic research that drives military capabilities and helps train the future STEM workforce.

Both instruments funded through the Army Research Office will be the only ones of their type in the United States and offer unique materials characterization capabilities needed to answer key materials engineering questions.

Novel DAC and RDAC

Valery Levitas, Anson Marston Distinguished Professor of Engineering, Vance Coffman Faculty Chair Professor in aerospace engineering, and faculty scientist at the U.S. Department of Energy’s Ames Laboratory, is designing and constructing a new type of dynamic panoramic diamond anvil cell (DAC) and dynamic rotational diamond anvil cell (RDAC) to examine materials at high-strain rates under high pressure and large deformations.

Levitas’ team will use the novel dynamic DAC and RDAC to advance experimental work on the behavior of materials important to the Department of Defense (as well as for two Levitas’ current NSF grants) – including strong ceramics and metals. The new technique will introduce strain rate as an additional parameter for studying phase transformations and viscoplastic properties. Levitas’ RDAC laboratory at Iowa State, developed with the support of another DURIP grant in 2017, is the only one in the USA.

“Gaining this new fundamental understanding of occurring processes – coupled with computational modeling – will speed the search for new materials and the understanding phenomena under high pressure, strain rates and large deformations,” said Levitas.

Micro-scale testing under extremes of temperature and strain rate

Sid Pathak, assistant professor of materials science and engineering, will expand the capabilities of the Alemnis in-situ micro-mechanical system to measure mechanical properties under extreme temperatures and high strain rates. The updated system, which operates in-situ inside a scanning electron microscope, will be capable of testing at up to 104/s strain rate, mimicking ballistic tests at the micron scale. Additionally, it can operate under cryogenic (-150 C) to elevated (1000 C) temperatures.

“Using this expanded system, we will be able to evaluate local material response over wide extremes of temperature, strain rates and loading conditions, not possible with any other existing instrumentation,” said Pathak.

Measuring at extreme conditions will open the doors to creating materials with superior performance in extreme conditions, including strong and tough nanocomposites, shape memory alloys that can morph for damage mitigation, high-performance materials for cryogenic use and more. Read more information about Pathak’s research here.

Strengthening the future

Both new instruments and techniques will be a unique hands-on educational opportunity for undergraduate and graduate student researchers and post-doctoral research associates.

“When tomorrow’s engineers train on one-of-a-kind techniques in Sid and Valery’s research groups, they gain one-of-a-kind expertise to find innovative solutions to pressing engineering challenges – at Iowa State and beyond,” said Arun Somani, associate dean for research, Anson Marston Distinguished Professor in Engineering, and Philip and Virginia Sproul Professor in Electrical and Computer Engineering.