Characterization of Nuclear Materials and Fuels with Advanced X-ray and Neutron Techniques: Poster Session
Sponsored by: TMS Structural Materials Division, TMS: Advanced Characterization, Testing, and Simulation Committee, TMS: Nuclear Materials Committee
Program Organizers: Xuan Zhang, Argonne National Laboratory; Jonathan Almer, Argonne National Laboratory; Maria Okuniewski, Purdue University; Joshua Kane, Idaho National Laboratory; Donald Brown, Los Alamos National Laboratory; J. Kennedy, Idaho National Laboratory; Arthur Motta, Pennsylvania State University
Monday 5:30 PM
March 15, 2021
Room: RM 51
Location: TMS2021 Virtual
Characterization of Microstructure, Texture, And Residual Stress in a Neutron Irradiated CANDU Pressure Tube: Abdulla Alawadi1; Hamidreza Abdolvand1; Michael Bach2; Sterling St Lawrence2; 1Western University; 2Canadian Nuclear Laboratories
In CANada Deterium Uranium (CANDU) nuclear reactors, pressure tubes are made of a Zr-2.5Nb alloy and are susceptible to the formation of brittle zirconium hydrides. The microstructure of the pressure tubes and the residual stresses that develop in the tubes can affect the hydrogen diffusion and hydrides formation. As such, understanding how the microstructure, texture, and residual stresses vary along the pressure tube is important. In this research, an extensive analysis of the microstructure and texture of three in-service neutron-irradiated pressure tube samples is conducted using EBSD. The results are subsequently compared to an unirradiated sample obtained from an offcut of the same tube. Furthermore, the measured grain maps are imported into the Abaqus FE solver to simulate the effects of thermal residual stresses that develop during the tubes manufacturing process. The effects of irradiation growth on the development of localized stresses are studied using crystal plasticity finite element modeling.
Synchrotron Microdiffraction Study of Cracks and Indentation on UO2 Material: Kun Mo1; Yinbin Miao1; Ruqing Xu1; Tiankai Yao2; Jie Lian3; Laura Jamison1; Abdellatif Yacout1; 1Argonne National Laboratory; 2Idaho National Laboratory; 3Rensselaer Polytechnic Institute
During operation of light water reactors, uranium dioxide (UO2) experiences both high temperature and large temperature gradients across the fuel pin. As UO2 lacks macroscopic plasticity, fractures and cracks are commonly found in fuel pellets. In this study, we applied an advanced synchrotron micro X-ray diffraction (μXRD) technique to study lattice strain development in cracking and indentation regions of micro-indented UO2 material, which was prepared by spark plasma sintering (SPS). Two of the indentations in the UO2 sample surface were selected to be studied by synchrotron µXRD. A method to corelate microstructures (cracks and other defects) observed in SEM and micro-diffraction measurements was presented. On the indented UO2 sample, the highest and lowest strained areas were found near the indentation tip and within the “open” crack, respectively. Induced by the residual stress, the lattice strain near the indentation was found to progressively decrease from the indentation boundary outwards.
X-ray Based Nanodiffraction to Study Strain in Materials for Nuclear Energy: Ericmoore Jossou1; Mehmet Topsakal1; Xiaojing Huang1; Khalid Hattar2; Hanfei Yan1; Yong Chu1; Cheng Sun3; Lingfeng He3; Jian Gan3; Lynne Ecker1; Simerjeet Gill1; 1Brookhaven National Laboratory; 2Sandia National Laboratories; 3Idaho National Laboratory
Understanding microstructural and strain evolutions induced by fission gas in nuclear fuel is crucial for designing next generation of nuclear reactors, as it is responsible for volumetric swelling and catastrophic failure in metallic fuels. Depth-resolved synchrotron X-ray nanodiffraction uniquely permits the measurement of lattice strain associated with irradiation-induced defects with sub-micron spatial resolution while X-ray fluorescence (XRF) enables 2D imaging of fission gas bubble positions with nanoscale resolution. Here, our recent work on residual lattice strain caused by krypton-ion-implantation in tungsten using a correlative multi-modal approach will be presented. For instance, the heterogeneous distribution of local defects accounts for the compressive and expansive lattice strain observed in the tungsten matrix. Beyond providing a detailed understanding of irradiation-induced microstructural changes in ion irradiated single crystal materials, this work demonstrates the utility of multi-modal scanning nanofocused X-ray measurements for the optimization of materials for the future nuclear reactors.