Maria Okuniewski Research

Research Interest

The over-arching goals of Dr. Okuniewski's research focus on understanding the connections between the microstructure of nuclear materials and fuels and their mechanical properties. The microstructural evolution is studied as a function of radiation damage and/or fabrication and processing of the nuclear systems. This research aims to connect phenomena that span multiple spatial (atomistic to mesoscale) and temporal (picoseconds to seconds) scales. Her research utilizes both experimental and modeling techniques in a complementary fashion. She has also been instrumental in developing new techniques and expanding the capabilities of existing techniques to apply to nuclear fuels and materials such as positron annihilation spectroscopy, nanoindentation, synchrotron X-ray diffraction and tomography, neutron diffraction, and focused ion beam/scanning electron microscopy applications.

Selected Publication

  1. A. Moore, C. Deo, M. I. Baskes, M. A. Okuniewski, Atomistic Mechanisms of Morphological Evolution and Segregation in U-Zr Alloys, submitted to Acta Materialia on December 17, 2015.
  2. W.-Y. Chen, Y. Miao, J.  Gan, M. A. Okuniewski, S. A. Maloy, J. F. Stubbins, Neutron Irradiation Effects in Fe and Fe-Cr at 300°C, Acta Materialia in press April 6, 2016.
  3. D. W. Brown, M. A. Okuniewski, B. Clausen, G. A. Moore, T. A. Sisneros, Neutron Diffraction Measurement of Residual Stresses in Al-clad U-10Mo Fuel Plates, Journal of Nuclear Materials, vol. 474 (2016) p. 8.
  4. A. E. Craft, D. M. Wachs, M. A. Okuniewski, D. L. Chichester, W. J. Williams, G. C. Papaioannou, A. T. Smolinski, Neutron Radiography of Irradiated Nuclear Fuel at Idaho National Laboratory, Proceedings from 10th World Conference on Neutron Radiography, October 5-10, 2014, Grindelwald, Switzerland, Physics Procedia v. 69 (2015) pp. 483-490.
  5. A. Moore, B. Beeler, C. Deo, M. I. Baskes, M. A. Okuniewski, Atomistic Modeling of High Temperature Uranium-Zirconium Alloys Structure and Thermodynamics, Journal of Nuclear Materials, vol. 467 (2015) p. 802.
  6. W.-Y. Chen, Y. Miao, Y. Wu, C. A. Tomchik, K. Mo, J.  Gan, M. A. Okuniewski, S. A. Maloy, J. F. Stubbins, Corrigendum to “Atom Probe Study of Irradiation Enhanced α′ Precipitation in Neutron-Irradiated Fe-Cr Model Alloys,” Journal of Nuclear Materials, vol. 467 (2015) p.392.
  7. K. R. Lund, K. G. Lynn, M. H. Weber, C. Macchi, A. Somoza, A. Juan, M. A. Okuniewski, Impurity Migration and Effects on Vacancy Formation Enthalpy in Polycrystalline Depleted Uranium,  Journal of Nuclear Materials, vol. 466 (2015) p. 343.
  8. W.-Y. Chen, Y. Miao, Y. Wu, C. A. Tomchik, K. Mo, J.  Gan, M. A. Okuniewski, S. A. Maloy, J. F. Stubbins, Atom Probe Study of Irradiation Enhanced α′ Precipitation in Neutron-Irradiated Fe-Cr Model Alloys, Journal of Nuclear Materials, vol. 462 (2015) p. 242.
  9. J. Hunter, D. Brown, M. Okuniewski, Evaluation of Computed Tomography of Mock Uranium Fuel Rods at the Advanced Photon Source, Canadian Institute for Non-Destructive Evaluation Journal, vol. 36 (2015).
  10. Y. Miao, B. Beeler, C. Deo, M. Baskes, M. A. Okuniewski, J. F. Stubbins, Defect Structures Induced by High-Energy Displacement Cascades in g Uranium, Journal of Nuclear Materials, vol. 456 (2015)  p. 1.
  11. J.  L. McDuffee, G. L. Bell, R. J. Ellis, R. W. Hobbs, M. A. Okuniewski, L. L. Snead, Design, Fabrication, and Testing of Gadolinium-Shielded Metal Fuel Samples in the Hydraulic Tube of the High Flux Isotope Reactor, Proceedings from 2014 Water Reactor Fuel Performance Meeting/Top Fuel/LWR Fuel Performance Meeting, Sendai, Japan, Sept. 14-17, 2014, Paper 100084.
  12. J. Hunter, D. Brown, M. Okuniewski, Evaluation of Computed Tomography of Mock Uranium Fuel Rods at the Advanced Photon Source, Proceedings of iCT, 5th Conference on Industrial Computed Tomography, Wels, Austria, Feb. 25-28, 2014, pp. 361-362.
  13. D. W. Brown, D. J. Alexander, K. D. Clarke, B. Clausen, M. A. Okuniewski, T. A. Sisneros, Elastic Properties of Rolled Uranium-10 wt.% Molybdenum Nuclear Fuel Foils, Scripta Materialia, vol. 69 (2013)  p. 666.
  14. P. Hosemann, J. N. Martos, D. Frazer, G. Vasudevamurthy, T.S. Byun,  J. D. Hunn,  B. C. Jolly, K. Terrani, M. A. Okuniewski, Mechanical Characteristics of SiC Coating Layer in TRISO Fuel Particles, Journal of Nuclear Materials, vol. 442 (2013) p. 133.
  15. K. R. Lund, K. G. Lynn, M. H. Weber, M. A. Okuniewski, Vacancy Formation Enthalpy in Polycrystalline Depleted Uranium, Journal of Physics: Conference Series, 16th International Conference on Positron Annihilation, vol. 443 (1), June 2013, pp. 1-4.
  16. D. W. Brown, M. A. Okuniewski, J. D. Almer, L. Balogh,  B. Clausen, J. S. Okasinski, B.H. Rabin, High Energy X-ray Diffraction Measurement of Residual Stresses in a Monolithic Aluminum Clad Uranium-10 wt% Molybdenum Fuel Plate Assembly, Journal of Nuclear Materials, vol. 441 (2013)  p. 252.
  17. B. Beeler, C. Deo, M. Baskes, M. Okuniewski, First Principles Calculations of the Structure and Elastic Constants of α, β, and γ Uranium, Journal of Nuclear Materials, vol. 433 (2013) p. 143.
  18. A. P. Moore, B. Beeler, M. Baskes, M. Okuniewski, C. S. Deo, Atomistic Ordering in Body Centered Cubic Uranium-Zirconium Alloy, MRS Proceedings, Symposium HH: Advances for Materials in Nuclear Energy, vol. 1514, January 2013,  pp. 27-35.
  19. B. Beeler, C. Deo, S. Rashkeev, M.  Baskes, M.  Okuniewski, Atomistic Investigations of Intrinsic and Extrinsic Point Defects in BCC Uranium,  ASTM Special Technical Publication, Effects of Radiation on Nuclear Materials: 25th Volume, vol. 1547 STP, January 2013, pp. 231-247.
  20. B. Beeler, C. Deo, M. Baskes, M. Okuniewski, Atomistic Properties of Gamma Uranium, Journal of Physics: Condensed Matter, vol. 24 (2012) p. 075401.
  21. B. Beeler, B. Good, S. Rashkeev, C. Deo, M. Baskes, and M. Okuniewski, First Principles Calculations of the Stability and Incorporation of Helium, Xenon, and Krypton in Uranium, Journal of Nuclear Materials, vol. 425 (2012), p. 2.
  22. R. R. Mohanty, J. Bush, M. A. Okuniewski, Y. H. Sohn, Thermotransport in γ(BCC) U-Zr alloys: A Phase-Field Model Study, Journal of Nuclear Materials, vol. 414 (2011), p. 211.
  23. B. Beeler, B. Good, S. Rashkeev, C. Deo, M. Baskes, and M. Okuniewski, First Principles Calculations for Defects in U, Journal of Physics Condensed Matter, vol. 22, n. 50 (2010), 505703.
  24. D. E. Burkes, D. M. Wachs, D. D. Keiser, M. A. Okuniewski, J-F Jue, F. J. Rice, R. Prabhakaran, Update on Fresh Fuel Characterization of U-Mo Alloys, Transactions from the Thirteenth International Topical Meeting on Research Reactor Fuel Management, RRFM 2009 (Vienna, Austria, March 2009). 
  25. D. E. Burkes, D. M. Wachs, D. D. Keiser, J.-F. Jue, J. Gan,  F. J. Rice, R. Prabhakaran, B. D. Miller, M. A. Okuniewski, Fresh Fuel Characterization of U-Mo Alloys, Proceedings of the 30th International Meeting on Reduced Enrichment for Research and Test Reactors (RERTR 2008), (Washington D.C., October 2008).
  26. C. A. Tomchik, M. A. Kirk, J. F. Stubbins, M. A. Okuniewski, and S. A. Maloy, In Situ Ion Irradiation of Iron Chromium Alloys, Proceedings of the First Workshop on the Use of In Situ TEM / Ion Accelerator Techniques in the Study of Radiation Damage in Solids, June 2008,  pp. 91-98C.
  27. C. S. Deo, S. G. Srinivasan, M. I. Baskes, S. A. Maloy, M. R. James, M. A. Okuniewski, and J. F. Stubbins, Kinetics of the Migration and Clustering of Extrinsic Gas in BCC Metals, ASTM Special Technical Publication, vol. 1492 (2008), p.177.
  28. C. S. Deo, S. G. Srivilliputhur, M. Baskes, S. Maloy, M. James, M. Okuniewski, J. Stubbins,  Kinetics of the Nucleation and Growth of Helium Bubbles in BCC Iron, Materials Research Society Symposium Proceedings: Materials in Extreme Environments, vol. 929, 2006, pp. 21-26.
  29. C. S. Deo, S. G. Srivilliputhur, S. A. Maloy, M. I. Baskes, M. R. James, M. A. Okuniewski, and J. F. Stubbins, Kinetics of the Migration and Clustering of Extrinsic Gas in BCC Metals, Journal of ASTM International, vol. 4, n. 9 (2007), JAI100698.
  30. C. S. Deo, M. A. Okuniewski, S. G. Srivilliputhur, S. A. Maloy, M. I. Baskes, M. R. James, and J. F. Stubbins, The Effects of Helium on Irradiation Damage in Single Crystal Iron, Journal of Nuclear Materials, v. 367-370 (2007), p. 451.
  31. C. S. Deo, M. A. Okuniewski, S. G. Srivilliputhur, S. A. Maloy, M. I. Baskes, M. R. James, and J. F. Stubbins, Helium Bubble Nucleation in BCC Iron Studied by Kinetic Monte Carlo Simulations, Journal of Nuclear Materials, v. 361 (2007), p. 141.
  32. M. A. Okuniewski, D. P. Wells, F. A. Selim, S. A. Maloy, M. R. James, J. F. Stubbins, C. S. Deo, S. G. Srinivasan, and M. I. Baskes, Positron Annihilation Spectroscopy of Proton Irradiated Single Crystal BCC Iron, Journal of Nuclear Materials, v. 351 (2006), p.149.
  33. A. Terekhov, B. J. Heuser, M. A. Okuniewski, R. S. Averback, S. Seifert, and P. R. Jemian, Small-Angle X-ray Scattering Measurements of Helium Bubble Formation in Borosilicate Glass, Journal of Applied Crystallography, v. 39 (2006), p. 647.
  34. M. A. Okuniewski, Y. Ashkenazy, B. J. Heuser, and R. S. Averback, Molecular Dynamics Simulations of Void and Helium Bubble Stability in Amorphous Silicon During Heavy-Ion Bombardment, Journal of Applied Physics, v. 96, n. 8 (2004), p. 4181.