Local Ordering in Materials and Its Impacts on Mechanical Behaviors, Radiation Damage, and Corrosion : Session IV
Sponsored by: TMS Structural Materials Division, TMS: Chemistry and Physics of Materials Committee, TMS: Nuclear Materials Committee, TMS: Corrosion and Environmental Effects Committee
Program Organizers: Penghui Cao, University of California, Irvine; Yang Yang, Pennsylvania State University; Fadi Abdeljawad, Lehigh University; Irene Beyerlein, University of California, Santa Barbara; Enrique Lavernia, University of California, Irvine; Robert Ritchie, University of California, Berkeley
Tuesday 2:30 PM
March 21, 2023
Room: Sapphire 411A
Location: Hilton
Session Chair: Yang Yang, The Pennsylvania State University; Penghui Cao, University of California, Irvine; Irene Beyerlein, University of California, Santa Barbara
2:30 PM Invited
Chemical Short-range Order and Passivation of Binary FCC and BCC Single-Phase Alloys: Karl Sieradzki1; Ian McCue2; James Rondinelli2; John Cavin2; 1Arizona State University; 2Northwestern University
Single-phase binary alloys containing a sufficient quantity of a passivating component such as Cr, Si, Al or a Pt-group metal form excellent protective passive films as a result of the formation of a nanometer-thick mixed oxide film. The key scientific question addressed in this presentation is whether chemical short-range order can be used as a materials processing “knob” that can be tuned to enhance the corrosion resistance of binary alloys at fixed composition. Results from both experimental electrochemical analysis and computational modeling will be presented. A necessary requirement of the percolation passivation theory is the selective dissolution of the non-passivating alloy component. Since the degree of selective dissolution is unknown in the case of most refractory alloys, it currently remains unclear whether the theory will be applicable to this class of alloys.Work supported by the National Science Foundation (NSF) program under grant numbers DMR- 2208848 and DMR-2208865.
3:00 PM Invited
Optimizing Passivation in Multiprincipal Element Alloys through Local Order: Mitra Taheri1; 1Johns Hopkins University
Multiprincipal element alloys, or high entropy alloys, have been the subject of much interest due to their tendency to exhibit local chemical and structural order. While this complexity of bonding environment has been connected to mechanical properties, only recently has any mechanistic connection between local order and corrosion resistance or passivation been investigated. In this talk, we reveal local ordering to be a key factor not only in alloy passivation, but also in alloy design and optimization. Specifically, the tendency for an alloy to possess clustering of particular elements was found to be tunable, and thus optimization of this clustering can lead to unexpected alloy stoichiometries exhibiting superior corrosion resistance. This interplay of order and passivation is discussed in the context of these results as well as broad design of alloys for extreme environments of corrosion and oxidation.
3:30 PM Invited
The Role of Short Range Ordering on the Corrosion Behavior of Structural Materials: John Scully1; Ho Lun Chan1; Debashish Sur1; Elena Romanovskaia1; 1University of Virginia
This talk compares the corrosion properties of Ni-Cr, and Fe-Cr and CoCrNi alloys in aqueous solutions and FLiNaK molten salt considering the effects of local order on corrosion behavior. Selected Fe-Cr and, Ni-Cr alloys and equi-atomic CoCrNi were tested when heat treated to form a as random solid solutions and also within the case of short range order creatinginvolving M-M and Cr-Cr clustering. The effects on Fe-Cr and, Fe-Cr and, and CoCrNi corrosion electrochemistry are presented.
4:00 PM Break
4:15 PM Invited
Dynamic Atomic-scale Understanding of the Initial Stages of Cu Oxidation Revealed by Correlated Environmental TEM and Theoretical Simulations: Judith Yang1; 1Brookhaven National Laboratory
Much is known about oxygen interaction with metal surfaces and the macroscopic growth of thermodynamically stable oxides. However, the transient stages of oxidation - from nucleation of the metal oxide to formation of the thermodynamically stable oxide - represent a scientifically challenging and technologically important terra incognito. To deepen our understanding of the atomic-scale dynamic processes of Cu oxidation, we are correlating in situ high-resolution environmental TEM (ETEM) with atomistic theoretical simulations. As an example, preferential monolayer-by-monolayer growth along Cu2O(110) planes was noted instead of along Cu2O(100) planes. Correlated Density Functional Theory (DFT) simulations show that the monolayer formation of Cu2O along Cu2O(110) was both thermodynamically and kinetically preferred over that of Cu2O(100) during Cu2O growth, in agreement with our experiments. These results shed new light on the epitaxial oxide growth mechanism and provide a deeper understanding of the dynamic processes and structural evolution involved in oxidation.
4:45 PM Invited
Multiscale Irradiation-induced Ordering in Metal Oxides: Janelle Wharry1; Hui Xiong2; Tristan Olsen2; Cyrus Koroni2; Andy Lau2; Dewen Hou2; Chao Yang1; Caleb Clement1; Khalid Hattar3; Yongqiang Wang4; Wei-Ying Chen5; 1Purdue University; 2Boise State University; 3Sandia National Laboratories; 4Los Alamos National Laboratory; 5Argonne National Laboratory
The objective of this talk is to understand irradiation-induced multiscale ordering – from crystallization to hierarchical nanostructuring – in metal oxide ceramics. Irradiation is generally understood to create disorder in materials; in fact, irradiation-induced amorphization of ordered intermetallics and ceramics is a well-established phenomenon. But there is growing evidence supporting irradiation-induced self-organization of extended defects such as bubble superlattices. This talk will further investigate irradiation-induced ordering phenomena across the length scales ranging from atomic- through micro-scale, focusing specifically on titania (TiO2). At the nano/micro-scale, we will discuss irradiation-induced hierarchical ordering in single crystal anatase TiO2. This hierarchical structure is comprised of bubble superlattices within a multi-layered damage structure of dislocation loops and nanocrystallites. Subsequently, at the atomic scale, we will discuss irradiation-induced crystallization of amorphous TiO2 nanotubes, and their effect on morphological stability. Proposed irradiation-induced ordering mechanisms will be discussed in the context of metal oxide functionality.
5:15 PM Invited
Ordering and Disordering of Helium Bubbles and Precipitates in Materials Studied Using Small Scale Mechanical Testing: Peter Hosemann1; Mehdi Balooch1; Yujun Xie2; H. V. Tin3; David Frazer4; 1University of California, Berkeley; 2University of California-Berkeley; 3Los Alamos National Laboratory; 4Idaho National Laboratory
Nuclear materials research features some of the most interesting and unique property-structure relationships in material science. Some unique defect structures that can only be created by radiation damage occur and lead to changed properties. Helium bubbles for example are usually created via nuclear reactions or direct ion implantation can create superlattices or align themselves on grain boundaries or dislocations leading to macroscopic issues such as embrittlement. Other treatments on nuclear materials such as long-term aging can also lead to ordered features such as found in the Ni-Cr system and again lead to macroscopic property changes that can lead to engineering concerns. However further radiation damage, excessive heat treatments, or ordinary plastic deformation can change these features and depending on the detailed mechanism destroy the ordered structures. However, other plastic deformation mechanism such as twinning can maintain the order or change the order while still accommodating a permanent shape change. In this work we feature how Helium bubble structures can change under plastic deformation and how Helium bubbles can be rearranged to cause larger defects. Further we investigate how the plastic deformation mechanism are influenced by ordered structures.
5:45 PM Invited
Exploring the Thermal, Mechanical, and Radiation Stability of Refractory High Entropy Alloys via In-situ Electron Microscopy: Khalid Hattar1; Eric Lang1; 1Sandia National Laboratories
For many high temperature applications ranging from rocket nozzles to plasma facing components of fusion energy systems, it is important to have structural materials that can maintain the associated original properties. A newer class of material with promise for these applications is refractory high entropy alloys (RHEA) or multi-component alloys (RMCA). In order to explore the stability of these new materials to high temperature, mechanical deformation, and radiation damage, we utilized in-situ SEM and TEM laser heating, nanoindentation and in-situ SEM notched bend tests, as well as in-situ TEM ion irradiation and helium implantation. Examples of each of these experimental findings will be presented. Generally, this broad study has shown that the stability of RHEA to these extreme environments is highly alloy dependent. SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525.