Dr. Yuri Osetskiy
Materials Science and Technology Division
Oak Ridge National Laboratory

Atomic Scale Mechanisms Operating in Structural Materials under Deformation

ABSTRACT: Structural materials in nuclear power devices suffer a significant modification of their microstructure under the intensive flux of energetic particles. These microstructures usually consist of small, nanometer-scale, defects, however their density can be as high as 10²⁴m^-3. This leads to a significant change in mechanical properties due to specific nano-scale mechanisms not amendable for elasticity calculations. Atomic scale modeling is the only technique that is applicable in such cases. Molecular dynamics based technique was applied for studying crystal plasticity mechanisms by modeling dynamics of dislocation-obstacles interactions. Three types of obstacles were studied such as localized obstacles (voids, bubbles, secondary phase precipitates), dislocation-type (dislocation loops, stacking fault tetrahedra, etc.) and solute hardening. In this presentation specific mechanisms will be described and demonstrated. Examples of modeling in situ straining experiments and nanoindentation will be also given.

BIOGRAPHY: Yury Osetskiy is a Senior Research Staff in the Materials Theory Group, Materials Science and Technology Division. He obtained his B.S+M.S in Physics + Materials Science from Moscow Engineering Physics Institute (Moscow, Russia) from 1976 to 1982. He got Ph.D. in Physics + Mathematics from Kurchatov Atomic Energy Institute (Moscow) in 1991. 11 years worked in Russian Research Centre "Kurchatov Institute" (Moscow) as an Engineer-Investigator and Senior Scientist (1982 to 1993). From 1993 to 1997 worked as an Expert-Investigator in Nuclear Technology Institute (Madrid, Spain), visiting scientist in Paul Scherrer Institute (Switzerland) and visiting professor in the Polytechnic University of Catalunya (Barcelona, Spain). From 1997 to 2003 he worked at the University of Liverpool (UK) as a University Research Fellow. From 2003 to present, he is a Senior Staff Member in Materials Science and Technology Division (ORNL).

He published >200 articles and book chapters and in 2003 was awarded with I.V.Kurchatov Honorary Medal for research in radiation materials science. His research interests include: theory and modeling of structural defects, diffusion, phase transformations, radiation damage and mechanical properties in metals and alloys.