Details
MAE Seminar: ML-Enabled High-Throughput Multidimensional Diffraction to Unravel Oxygen-Driven Metastability and Strengthening in BCC Refractory Alloys
Date: September 29, 2026
Time: 12:50 PM Location: MAE-A 303
Dr. Ravit Silverstein
Assistant Professor
Department of Material Science and Engineering
University of Florida
Abstract
The mechanical performance of body-centered cubic (BCC) multi-principal element alloys (MPEAs) is closely linked to short-range order, subtle lattice changes, and strain heterogeneity, all of which can be thermodynamically modulated by interstitial alloying. Understanding their role in strengthening and plasticity requires approaches capable of resolving structural, chemical, and mechanical information across
multiple length scales, with structural sensitivity down to the sub-angstrom scale. Recent advances in multidimensional diffraction, including 4D-scanning transmission electron microscopy (4D-STEM),
provide unprecedented experimental access to this complexity. By integrating 4D-STEM and spectroscopy with ML and generative libraries of metastable structures, we can identify early-stage transformation
pathways that are difficult to capture using conventional characterization approaches. In this talk, I will use Nb-rich Ti–Nb alloys containing dilute (~1 at.%) oxygen additions as a model system. The results reveal
that controlled oxygen additions can reshape the BCC thermodynamic energy landscape, inducing competing decomposition modes involving Burgers-related transient structures toward the hexagonal close-packed (α-HCP) phase. By quantifying compositional undulations and strain heterogeneity with small-scale mechanical testing, we establish direct links between phase decomposition and mechanical performance. This framework provides a foundation for future autonomous characterization and navigation of interstitial-mediated transformations toward the design of stronger, more ductile refractory alloys.
Biography
Silverstein is an assistant professor in MSE at UF. Prior to joining UF, she was a Research Scientist in the Materials Department at UCSB, where she managed the Microscopy suite and led interdisciplinary
research combining advanced electron microscopy and materials design. Silverstein earned her doctorate in Materials Engineering from Ben-Gurion University, studying hydrogen embrittlement mechanisms
under high-strain-rate loading using flyer-plate impact experiments, while holding a Research Associate position in the Applied Physics Division at Soreq Research Center. Silverstein subsequently completed two
postdoctoral fellowships at UCSB focused on refractory alloy design and ceramic matrix composite processing. Her current research focuses on designing and processing stronger and tougher materials
operating in extreme environments. Silverstein uses time-resolved multimodal 4D-STEM coupled with X-ray energy-dispersive and electron energy-loss spectroscopy (XEDS and EELS) to track changes in
chemistry, structure, and strain during in situ heating and mechanical loading, revealing mechanisms governing phase transformations, deformation, and performance.
Faculty Host: Dr. Douglas Spearot