General Poster Session: Nuclear Materials
Program Organizers: TMS Administration

Monday 5:30 PM
February 24, 2020
Room: Sails Pavilion
Location: San Diego Convention Ctr


Cancelled
H-67: Deformation Studies on Highly Irradiated RPV Steels Using Advanced Instrumented Technique: Mikhail Sokolov1; Maxim Gussev1; Robert Odette1; 1Oak Ridge National Laboratory
    Large number of reactor pressure vessel steels were irradiated to very high doses, approximately 1x1020 n/cm2, in ATR-2 experiment designed by UCSB. Three materials with relatively high Nickel and high and medium Copper contents were selected for current investigation. Tensile testing with digital image correlation (DIC) was used to investigate strain maps and rates in these highly radiation sensitive materials before and after irradiation, as well as after annealing at 450oC and 500oC. It is shown that irradiation significantly changes the plastic deformation behavior of irradiated steels. Annealing results in some recovery of tensile properties. However, the stain rates of annealed material are completely different from unirradiated and irradiated conditions.

H-68: Influence of Grain Size and Precipitates on Tellurium Corrosion Behaviors of GH3535 Alloy: Li Jiang1; Zhi Jun Li1; 1Shanghai Institute Of Applied Physics
     The effects of grain boundary engineering (GBE) treatment, grain size and deformation state on the tellurium (Te) corrosion behaviors of GH3535 alloy have been investigated systematically in this study. It was found that GBE-treated alloy and the fine-grained one can effectively decrease the density and depth of Te diffusion along the grain boundaries respectively, which is related to the grain boundary character distribution. Moreover, the hot-rolled GH3535 can completely suppress the Te corrosion and Te-induce cracking both in depth and density. In the hot-rolled alloy, the higher proportion of Cr3Te4 and MnTe in the corrosion product scales help to impede the inward diffusion of Te atoms, and the high-density interfaces of the primary M6C carbides trap and exclude Te atoms from the grain boundaries, which jointly contribute to the better Te corrosion and cracking resistance of the hot-rolled alloy.

H-69: Systematic Analysis on the Primary Radiation Damage in Th1-xUxO2 Fluorite Systems: Miaoimao Jin1; Chao Jiang1; 1Idaho National Laboratory
    Primary radiation damage featuring rapid atomic collisions and thermal spikes constitute the foundation of a high-fidelity description of radiation-assisted microstructure evolution. Mixed oxide system Th1-xUxO2 with fluorite structure experiences intense irradiation as nuclear fuels. To systematically describe the primary damage, we consider the effect of temperature, composition, and primary-knock atom energy on defect generation. A holistic functional form is developed to effectively quantify the number of defects, and the exponential truncated power-law can well describe defect cluster size distribution. Finally, the defect (cluster) structures are elaborated, notably that vacancy clusters converge to charge balanced state with increasing size and interstitial clusters can embrace high symmetry. These results provide both a high-level description and a detail atomic understanding towards the radiation-induced defects in fuel oxide, which can serve as input to meso-scale simulations for long time scale and large spatial scale microstructure evolution.

H-70: The Interaction between the Oxidation and Tellurium Corrosion in the Ni-based Superalloy: Zhijun Li1; 1SINAP
    The uncertainty in the low-activity tellurium (Te) corrosion experiments has puzzled researchers for decades and makes the assessment of the tellurium embrittlement resistance of alloys for molten salt reactors impossible. The dramatic role of hydroxyl radicals in the Te corrosion behaviors of Ni-12Mo-7Cr-1Nb based superalloy was first reported. The hydroxyl radicals escape from the quartz tubes and oxidize the Cr element in the alloy to form Cr2O3 layers, which significantly suppress the Te corrosion. This work reveals The interaction between the oxidation and Tellurium corrosion in this alloy, which is the key factor in the corrosion experiment.