Methods, Techniques, and Materials Discovery of Irradiation Effect Using In-situ Microscopy: In-situ Microscopy under Irradiation
Sponsored by: TMS Structural Materials Division, TMS: Nuclear Materials Committee, TMS: Advanced Characterization, Testing, and Simulation Committee
Program Organizers: Wei-Ying Chen, Argonne National Laboratory; Xuan Zhang, Argonne National Laboratory; Kevin Field, University of Michigan; Donald Brown, Los Alamos National Laboratory; Aida Amroussia, GE Global Research
Monday 8:30 AM
March 20, 2023
Room: 25A
Location: SDCC
Session Chair: Kevin Field, University of Michigan
8:30 AM Invited
High Throughput Assessment of Advanced Nuclear Materials via In-situ TEM: Osman El-Atwani1; Enrique Martinez2; Andrew Alvarado1; Meimei Li3; 1Los Alamos National Laboratory; 2Clemson University; 3Argonne National Laboratory
In-situ electron microscopy characterization techniques of nuclear materials are vital tools assisting in the fundamental understanding of the atomistic processes which give rise to the material’s response under extreme environments. Here we present in-situ transmission electron microscopy (TEM) characterization of advanced nuclear materials and their dynamic response to extreme irradiation conditions. Several material examples will be discussed including pure materials and high entropy alloys. We demonstrate irradiation damage evolution as a function of dose in terms of grain size growth, dislocation loop formation and void and bubble formation. The advantages and some limitations of the use of in-situ TEM techniques to solve nuclear materials problems and to fundamentally understand different and complex materials response to various extreme irradiation environments (including dual beams) will be presented.
9:00 AM
Effect of Stacking Fault Energy on Microstructural Evolution of Compositionally Complex Alloys under In situ Dual-beam Heavy-ion Irradiation: Calvin Parkin1; Boris Maioriv2; Kumar Sridharan1; Wei-Ying Chen3; Meimei Li3; Adrien Couet1; 1University of Wisconsin-Madison; 2Los Alamos National Laboratory; 3Argonne National Laboratory
Compositionally complex alloys (CCAs) with a base matrix of four or more principal alloying elements may resist radiation degradation by void swelling due to unique energy and mass transport properties. Because the steady-state swelling rate of austenitic alloys is consistent after voids nucleate (1%/dpa), the effect of composition on nucleation in a bubble-stabilizing He environment was investigated and presented at TMS2022. Heavy-ion irradiation of two CCAs, Cr15Fe35Mn15Ni35 and Cr18Fe27Mn27Ni28 were performed at the IVEM-Tandem facility at ANL using 1 MeV Kr++ and 16 keV He+ co-implantation up to 7 dpa and 0.75% He/dpa at temperatures of 773K and 873K. Results were compared to less compositionally complex single-phase FCC materials and discussed alongside single-beam high-temperature in situ and high-dpa ex situ irradiations. The difference in faulted loop populations was attributed to the stacking-fault energy, which has recently been measured experimentally using TEM to be lower in Cr15Fe35Mn15Ni35 than in Cr18Fe27Mn27Ni28.
9:20 AM
Observations of ‘Far from Equilibrium’ Phenomena under in Reactor Thermal Conditions Using In Situ TEM: Sriram Vijayan1; Kaustubh Bawane2; Lingfeng He2; Fidelma Di Lemma2; Joerg Jinschek3; 1The Ohio State University; 2Idaho National Laboratory; 3Technical University of Denmark (DTU)
During nuclear fission, the in reactor thermal conditions results in large thermal gradients across the fuel pellet and cladding material. These extreme thermal gradients result in non-equilibrium phenomena such as redistribution of constituent elements and fission products along the thermal gradient. Currently, this information can only be observed through post-mortem characterization of fuel rod cross sections. In order to study the dynamic processes that govern the microstructural evolution under in reactor thermal conditions at high spatial resolution and correlate them to fuel properties and performance, the development of a new in-situ heating device is needed. Here, we discuss the methodology to modify a micro electro mechanical (MEMS) based TEM heating device, to study the effect of in reactor thermal gradients on the microstructural evolution in a lamella prepared from a metallic nuclear fuel alloy sample. Additionally, the challenges and opportunities associated with this novel approach will be discussed.
9:40 AM
Discovering the Mechanisms of Helium Channel Evolution Via In-situ Annealing and Observation in TEM: Digvijay Yadav1; Ryan Schoell2; Eric Lang2; Benjamin Derby3; Jon Kevin Baldwin3; Nan Li3; Khalid Hattar2; Michael Demkowicz1; Kelvin Xie1; 1Texas A&M University; 2Sandia National Laboratory; 3Los Alamos National Laboratory
We investigate the mechanism of helium (He) channel formation and coarsening in a vanadium-copper-vanadium (V-Cu-V) tri-layer under in-situ He implantation in the in-situ ion irradiation TEM (I3TEM) facility at Sandia National Laboratory. The implantation parameters are chosen such that most of the He is trapped in the Cu layer. The nanometer-scale thickness of this layer confines the growth of He bubbles, forcing them to interact and interconnect into high aspect ratio channels. Our study resolves this process as a function of time. Moreover, by performing electron microscopy under in situ annealing, we also investigate the transformation of He-filled channels into coarser, pancake-shaped cavities. The implications of our work for understanding He behavior in nanocomposite metals are discussed.
10:00 AM Break
10:20 AM Invited
Rare-earth Titanates Ln2TiO5 Crystal Chemistry and Radiation Response. A Review.: Rob Aughterson1; 1Australian Nuclear Science and Technology Organisation
Analysis of related Ln2TiO5 compounds coupled with crystal structure detail in this study provides systematic and comprehensive ion-irradiation experimental data allowing trends and fundamental theories to be developed. In situ ion-irradiation coupled with transmission electron microscopy (TEM) and electron diffraction are used for radiation damage response observation to simulate the damage effects of high-energy particles such as those from alpha-decay. Of particular focus, SADPs were used to determine the critical fluence of irradiating ions required for the transition from crystalline to amorphous allowing radiation response of the various ceramics to be compared. The critical fluence was also determined at a variety of temperatures allowing a critical temperature for maintaining crystallinity to be quantified. By defining the effect of crystal chemistry on ion-irradiation response complex ceramic compounds can be tailored to give the best possible properties for application. This is a first step in the process of validation for nuclear-based applications.
10:50 AM
Radiation Tolerance of Amorphous Alumina Cladding Coatings for Heavy Liquid Metal Cooled Fast Reactors: Temperature and Dose Effect.: Davide Loiacono1; Mattia Cabrioli1; Wei Ying Chen2; Meimei Li2; Fabio Di Fonzo3; 1Politecnico di MIlano; 2Argonne national Laboratory; 3IIT
Considering the requirements for the materials development for Generation-IV nuclear reactors, ceramics represent an up-and-coming class of materials due to their high-temperature strength and excellent corrosion resistance. In this respect, we studied an amorphous Al2O3 coating produced by Pulsed Laser Deposition. As a surrogate for neutron irradiation, heavy-ions have been used in in-situ tests performed at temperatures from 400 to 800°C. The range of temperatures studied allowed us to prove how the material does not crystallize below a threshold temperature (400 °C) even at a remarkably high radiation dose level (~30 DPA), preserving its amorphous and void-free structure. At higher temperatures, radiation-induced the crystallization even below 600°C (Al2O3 crystallization temperature). Crystallization activation energy, grain dimensions distribution, phase evolution, and the correlation between temperature and radiation effect were extrapolated. This study lays the foundation for the rational use of ceramic coatings as a protective barrier.
11:10 AM
Understanding the Amorphization Limit in Irradiated Ceramics via Repeated In situ Recrystallization Experiments: Nathan Madden1; Matthew Janish2; Wei-Ying Cheng3; Meimei Li3; Blas Uberuaga2; Jessica Krogstad1; 1University of Illinois at Urbana-Champaign; 2Los Alamos National Laboratory; 3Argonne National Laboratory
In situ irradiation has been a powerful tool for experimentally probing the amorphization limit in a range of materials, especially pyrochlore-based ceramics. However, visual inspection of electron diffraction patterns is somewhat subjective and may overlook residual, localized structural motifs that cannot be rigorously determined solely via traditional electron diffraction techniques. The presence and importance of such localized order will be demonstrated in single crystal gadolinium titanate (Gd2Ti2O7) specimens. A combination of in situ heating and ion irradiation are leveraged to understand the impact of residual (dis-)order on the recrystallization behavior and subsequent radiation tolerance. Repeated cycling between the amorphous and crystalline states revealed that both the recrystallization temperature and amorphization threshold are dependent on the sample history.
11:30 AM
Helium Effects on Defect Evolution of In-situ Irradiated Additive-manufactured Grade 91 Steel: Yan-Ru Lin1; Arunodaya Bhattacharya1; Wei-Ying Chen2; Steven Zinkle3; 1Oak Ridge National Laboratory; 2Argonne National Laboratory; 3University of Tennessee
The microstructural responses under eight in-situ single (Fe or He) and dual (Fe and He) ion-beam irradiation conditions of additive-manufactured (AM) Grade-91 steel using a powder-based directed energy deposition (DED) technique with post-build heat treatments were investigated. The 3D printed materials were irradiated with 400 KeV Fe and/or 15 KeV He at 500-600°C to 0.6-1.2 dpa with He content of 0-20 at%. Using the Intermediate Voltage Electron Microscopy-Tandem facility in Argonne National Laboratory, the dynamic evolution of dislocation lines, dislocation loops, and cavities were analyzed by transmission electron microscopy. With the addition of He implanted atoms, the dislocation loop density increased while the loop diameter decreased. Cavities were only found in the conditions with single He ion and dual Fe+He ion irradiations. The incubation period of cavities as well as the distribution of cavities near the primitive particles, grain boundary, or dislocation loops will be presented.