Author: Jack Darrell

Supported by a three-year, $700,000 grant from the National Science Foundation, a team of Johns Hopkins researchers led by Tim Weihs and Michael Falk, professors in the Department of Materials Science and Engineering, is working to advance the development and manufacture of light metal alloys by delving into how the materials behave at the molecular level.

The team is investigating the causes of molecular defects in light metal alloys that happen during the manufacturing process. These imperfections, referred to as “vacancies,” occur in areas where atoms are missing from the alloy’s crystal structure, and are caused by changes in temperature and strain during production. The team successfully simulated a technique for merging these imperfections or transforming them into minuscule nano-sized bubbles, enhancing the alloy’s strength.

“This insight opens the door to new energy-efficient methods for engineering strong and durable light metal alloys—a critical step toward lightweight vehicles and other applications. We look forward to experimentally testing these findings,” said Falk.

Enabling the efficient production of new materials that provide strength without adding weight means these materials could be used in vehicles, protective equipment, and space exploration, according to Sreenivas Raguraman, a third-year PhD student involved in the project.

“Improving the manufacturing process will result in better, more consistent materials, including those with the potential to advance public welfare and defense,” he said.

Tim Weihs, professor of materials science and co-principal investigator on the project, believes that one of the great strengths of this investigation is the extensive collaboration involved. The project not only brings together researchers from the Department of Materials Science and Engineering and the Hopkins Extreme Materials Institute but also engages undergraduates from Morgan State University, a nearby historically Black university. As part of this work, Weihs and Falk will host a workshop on extreme vacancy engineering at Morgan State.

“This award involves teamwork on multiple levels, including with external partners,” said Weihs.

During the project, Raguraman will travel to the National Institute of Standards and Technology and Pacific Northwest National Laboratory to carry out Focused Ion Beam and Atom Probe studies, as well as to Washington State University to assist with positron work.

“It’s very exciting being able to work with this many talented scientists across the country,” he said.

The preliminary simulations that made the grant possible were created by Vicente Munizaga, a Hopkins graduate student in physics who noted the potential that this kind of computational work could have in the future.

“Advanced computational simulations allow for the exploration of pathways during nucleation that usually are overlooked. These simulations revealed all these interplays of molecular interactions. For me, it shed light on the fundamental mechanisms that govern nucleation, which paves the way for more precise control and manipulation at the nanoscale. In other words, opening new frontiers in material science and beyond.”