Researchers at MIT have discovered that metals retain subtle atomic patterns even after standard manufacturing processes, challenging long-held assumptions. These patterns, driven by microscopic dislocations, could enable engineers to customize material properties for demanding applications. The finding, published in Nature Communications, reveals a new physical principle in metallurgy.
For years, scientists believed that atomic patterns in metal alloys vanished during manufacturing, leaving atoms in a random state. However, MIT researchers have shown that these subtle chemical arrangements persist, influencing key properties like strength, durability, heat resistance, and radiation tolerance.
The team, led by Rodrigo Freitas, the TDK Assistant Professor in MIT's Department of Materials Science and Engineering, used advanced machine-learning simulations to model atomic behavior during metal processing. They simulated deformation and heating—common steps in manufacturing—and tracked how atoms rearranged. Surprisingly, the metals never reached complete randomness.
"The conclusion is: You can never completely randomize the atoms in a metal. It doesn't matter how you process it," Freitas explains. "This is the first paper showing these non-equilibrium states that are retained in the metal."
The study identified that these patterns stem from dislocations, irregular distortions in the atomic lattice. During deformation, dislocations guide atoms into preferred positions by favoring low-energy pathways, creating stable 'far-from-equilibrium states.' Co-first authors Mahmudul Islam, Yifan Cao, and Killian Sheriff contributed to the high-precision models and large-scale simulations.
Published in Nature Communications (2025; 16(1), DOI: 10.1038/s41467-025-64733-z), the work was supported by the U.S. Air Force Office of Scientific Research's Young Investigator Program, MathWorks, and the MIT-Portugal Program. Freitas notes potential impacts on catalysis, electrochemistry, and radiation damage in nuclear reactors.
"Researchers have been looking at the ways these atomic arrangements change metallic properties—a big one is catalysis," Freitas says. Applications could extend to aerospace alloys, where understanding atomic shuffling is key to balancing strength and low density.