Maintaining our present nuclear reactors and developing next generation systems relies critically on understanding materials performance under extreme conditions of high-temperature, corrosion, and irradiation. Atomistic modeling can provide powerful insight into irradiation effects, and we have pioneered the use of molecular based transport modeling to understand such phenonmena as thermal and radiation induced segregation[9-11] and precipitation[12] in nuclear steels. We have also studied a wide range of phenomena in SiC, both irradiation effects and fission product transport, and this work has been lead by Prof. Izabela Szlufarska, a leading expert in this material (see materials for nuclear reactors). Other aspects of nuclear materials, including fission product sorption in carbons and molten salts for heat transfer and pyroprocessing, are also areas of study in our group.
[9] J. D. Tucker, R. Najafabadi, T. R. Allen, and D. Morgan, Ab initio-based diffusion theory and tracer diffusion in Ni-Cr and Ni-Fe alloys, Journal of Nuclear Materials 405, p. 216-234 (2010).
[10] S. Choudhury, L. Barnard, J. D. Tucker, T. R. Allen, B. D. Wirth, M. Asta, and D. Morgan, Ab-initio based modeling of diffusion in dilute bcc Fe-Ni and Fe-Cr alloys and implications for radiation induced segregation, Journal of Nuclear Materials 411, p. 1-14 (2011).
[11] K. G. Field, L. M. Barnard, C. M. Parish, J. T. Busby, D. Morgan, and T. R. Allen, Dependence on grain boundary structure of radiation induced segregation in a 9wt.% Cr model ferritic/martensitic steel, Journal of Nuclear Materials 435, p. 172-180 (2013)
[12] L. Barnard, N. Cunningham, G. R. Odette, I. Szlufarska, and D. Morgan, Thermodynamic and kinetic modeling of oxide precipitation in nanostructured ferritic alloys, In preparation (2013).
(a) Model predictions of Cr radiation induced segregation in Fe-Cr model alloy compared to experimental values for a range of grain boundary types. (b) Specific concentration profile of Cr around a grain boundary after irradiation as predicted by oiur models and measured experimentally. Data from Ref. [11]).