Tiberiu Stan, Ph.D.

Postdoctoral Fellow
Northwestern University
Materials Science and Engineering
Voorhees Research Group

Office: Cook 4019
Email: tiberiu.stan@northwestern.edu

Ph.D. – Materials Science and Engineering
University of California Santa Barbara

B.S. – Physics
University of California Santa Barbara

Tiberiu Stan studies eutectic solidification and grain growth using 4D x-ray tomography. When a metal is cooled from the liquid, in nearly all cases from castings to additive manufacturing, the metal freezes via the formation of dendrites. While the aluminum industry alone creates billions of dendrites each year, the mechanisms by which these dendrites evolve remain controversial and poorly understood. We use synchrotron x-ray computer tomography (XCT) to provide direct in situ observations of dendrite nucleation, growth, and coarsening. The non-destructive nature of the method enables the study of microstructural evolution in four dimensions (space and time). Using high-performance computing along with advanced visualization and analysis techniques, the 4D XCT studies provide new insights into the fundamental physics governing dendritic solidification in metallic alloys.

Publications

  1. D.J. Sprouster, R. Weidner, S.K. Ghose, E. Dooryhee, T.J. Novakowski, T. Stan, P. Wells, N. Almirall, G.R. Odette, L.E. Ecker, “Infrastructure development for radioactive materials at the NSLS-II”, Nuclear Instruments and Methods in Physics Research Section A, (2017) doi: 10.1016/j.nima.2017.10.053
  2. T. Stan, Y. Wu, G.R. Odette, H.D. Zhou, “Epitaxial Fe thin films on {100} Y2Ti2O7: model interfaces for nano-oxide dispersion strengthened steels”, Metallurgical and Materials Transactions A, 48 (2017) 11, pp. 5658-5666. doi: 10.1007/s11661-017-4283-7
  3. T. Stan, D.J. Sprouster, G.R. Odette, L.E. Ecker, I. Charit, “X-ray absorption spectroscopy characterization of embedded and extracted nano-oxides”, Journal of Alloys and Compounds, 699 (2017) pp. 1030-1035. doi: 10.1016/j.jallcom.2016.12.350
  4. D.J. Sprouster, J. Sinsheimer, E. Dooryhee, S.K. Ghose, P. Wells, T. Stan, N. Almirall, G.R. Odette, L.E. Ecker, “Structural characterization of nanoscale intermetallic precipitates in highly neutron irradiated reactor pressure vessel steels”, Scripta Materialia, Vol. 113 (2016) pp. 18–22. doi: 10.1016/j.scriptamat.2015.10.019
  5. T. Stan, Y. Wu, G.R. Odette, K.E. Sickafus, H.A. Dabkowska, B.D. Gaulin, “Fabrication and characterization of naturally selected epitaxial Fe – {111}Y2Ti2O7 mesoscopic interfaces: some potential implications to nano-oxide dispersion strengthened steels”, Metallurgical and Materials Transactions A, 44 (2013) 10, pp. 4505–4512. doi: 10.1007/s11661-013-1827-3