Nanostructured Materials in Extreme Environments: Nanostructured Metals in High Temperature Environments
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS Structural Materials Division, TMS: Nanomechanical Materials Behavior Committee, TMS: Advanced Characterization, Testing, and Simulation Committee, TMS: Mechanical Behavior of Materials Committee, TMS: Nuclear Materials Committee
Program Organizers: Haiming Wen, Missouri University of Science and Technology; Nan Li, Los Alamos National Laboratory; Youxing Chen, University of North Carolina Charlotte; Yue Fan, University of Michigan; Niaz Abdolrahim, University of Rochester; Khalid Hattar, University of Tennessee Knoxville; Ruslan Valiev, UFA State Aviation Technical University; Zhaoping Lu, University of Science and Technology Beijing
Monday 2:00 PM
March 20, 2023
Room: Aqua 303
Location: Hilton
Session Chair: Benjamin Derby, Los Alamos National Laboratory
2:00 PM Invited
Interface Mediated Strain at High Temperatures: Shen Dillon1; 1University of California, Irvine
Coble introduced a model that is effective in predicting the rate of interfacial strain at relatively high applied stresses. Below some threshold stress, this model breaks down and the stress dependence of the strain rate generally follows a power law relationship. The physical basis for such a relationship remains poorly understood. In situ TEM-based high temperature interfacial creep experiments indicate that interfaces and grain boundaries do not typically contain the relatively high energy interfacial dislocations necessary to mediate creep. At low stresses, the kinetics tend to be nucleation rate limited up to stresses much higher than the onset of Coble creep in bulk materials. This talk seeks to rationalize the discrepancy between both the power law and exponential response and the relative magnitude of the stresses by considering the influence of microstructure on interface mediated creep. The result is a basic model utilized to understand or predict creep kinetics.
2:25 PM Invited
Can Engineered Nanostructures Enhance the Performance of Tungsten for Extreme Environments?: Jason Trelewicz1; 1Stony Brook University
The advancements in solute stabilized binary nanocrystalline alloys have motivated the pursuit of synergistic effects in ternary systems combining different alloying elements for enhancing stability and performance. Future fusion reactors provide an unprecedented challenge for materials stability, where even high melting temperature refractory metals are limited in such environments. The unique thermodynamic state occupied by nanocrystalline alloys provides an opportunity to access new stability regimes, which are explored in this presentation for combating structural instabilities in tungsten. We map compositional complexities in the W-Ti-Cr system through lattice Monte Carlo simulations to produce alloy design maps. A series of ternary nanostructured tungsten alloys are subsequently synthesized through high energy ball milling with in situ synchrotron x-ray diffraction employed for mapping microstructural stability and evolution up to 1500 °C. Bulk alloys retaining ultrafine grained microstructures are synthesized through field assisted sintering, thus demonstrating simultaneous stability and manufacturability enabled by synergistic alloy design.
2:50 PM
Uncovering the Transition from Helium Clustering to Bimodal Cavity Distributions in Tungsten: Cormac Killeen1; Yang Zhang1; David Sprouster1; Jason Trelewicz1; 1Stony Brook University
In the characterization of gaseous defects that form due to, e.g., transmutation or ion implantation, it is often difficult to probe the incubation stages of bubble formation. This process involves a transition from defect clustering to the nucleation of bubbles and its biasing to various microstructural features. Here, we explore this transition during helium implantation in tungsten as a function of fluence and temperature using a microstructurally informed multi-modal synchrotron approach. Results indicate that low implantation temperatures favor the formation of small sub-nanometer scale helium clusters irresolvable via TEM but accompanied by nanoscale bubble formation homogeneously distributed between the grain matrix and boundary. Higher temperatures lead to a bimodal distribution of small nanometer intragranular bubbles, larger cavities biased to the grain boundaries, and a decrease in the helium cluster fraction. The mechanisms underpinning the transition with fluence, and implications of irradiation temperature, are discussed using insights from molecular dynamics simulations.
3:10 PM
Microstructural Evolution of Refractory-based Nanomultilayers at Elevated Temperatures: Kyle Russell1; Andrea Hodge1; 1University of Southern California
Nanometallic multilayers are highly tailorable thin films that have demonstrated remarkable mechanical properties and resistance to both irradiation and corrosion damage due to a high density of interfaces. However, the engineering utility of nanomultilayers is limited by thermal instability caused by their high interfacial density, which provides a significant driving force for microstructural transformations. Prior studies have identified interfacial energetics as playing a significant role in determining layer stability but primarily focused on examining crystalline/crystalline interfaces. In order to expand our understanding of thermally induced degradation mechanisms in NMs, amorphous/crystalline interfaces must also be explored and analyzed. This work investigates the effects of varying characteristics of metallic glass FeW layers within a Fe/FeW nanolaminate structure on thermal stability by examining microstructural evolution via differential scanning calorimetry and ex-situ transmission electron microscopy characterization techniques at different temperatures.
3:30 PM Break
3:50 PM Invited
Nanostructured Metals with Dispersed Nanoparticles: Xiaochun Li1; Enrique Lavernia2; Diran Apelian2; Julie Schoenung2; 1University of California, Los Angeles; 2University of California, Irvine
Nanostructured metals with dispersed nanoparticles have been successfully manufactured to offer extraordinary properties for practical applications. This talk is to discuss some recent progress in the processing and properties of nanostructured metals containing nanoparticles. First, it will present a new discovery that nanoparticles can refine metal grains to ultrafine/nano scale by instilling a continuous nucleation and growth control mechanism during slow cooling. The bulk ultrafine grained/nanocrystalline metals with nanoparticles offer an unprecedented thermal stability. Second, it will then discuss about the Selective Laser Melting of aluminum with dense nanoparticles to deliver one of the highest specific Young’s modulus and specific yield strengths among structural metals, as well as an improved specific strength and thermal stability up to 400 °C. Finally, it will focus on a new dispersion mechanism of oxide nanoparticles in molten metals for manufacturing ODS alloys via liquid metallurgy for applications in extreme environments.
4:15 PM Invited
Nb Solubility in Cu Grain Boundaries: Emmeline Sheu1; Jon Baldwin2; Darrick Williams2; Michael Demkowicz1; 1Texas A&M University; 2Los Alamos National Laboratory
The equilibrium solubility of niobium(Nb) in copper(Cu) is miniscule. We present experimental evidence that Nb nevertheless has significant solubility in certain Cu grain boundaries (GBs). We synthesize a tri-layer sample consisting of a Cu layer deposited on a Nb substrate and a molybdenum (Mo) layer deposited on the Cu. After a brief, high-temperature anneal, we observe Nb in solution within the Mo layer immediately adjacent to certain GBs in the Cu layer. Upon further annealing, the Nb content in the Mo increases, eventually forming a continuous layer of Mo-Nb solid solution that increases in thickness with continued annealing. We conclude that Nb is permeating through Cu GBs and mixing with the Mo. The permeability of Nb through Cu GBs is evidence of Nb solubility within those GBs. Notably, some Cu GBs exhibit no Nb permeability, demonstrating that Nb solubility in Cu GBs depend on the crystallographic character of the GBs.
4:40 PM Cancelled
High-temperature Evolution of Nano-structured High-entropy Alloys and Stainless Steel as Studied by In-situ Neutron and Synchrotron X-ray Diffraction: Klaus-Dieter Liss1; Xiaojing Liu1; Jae-Kyung Han2; Yusuke Onuki3; Malte Blankenburg4; Megumi Kawasaki2; 1Guangdong Technion - Israel Institute of Technology (GTIIT); 2Oregon State University; 3Ibaraki University; 4Deutsches Elektronen-Synchrotron (DESY)
The nano-structured materials have been produces by high-pressure torsion processing. In-situ diffraction methods are used to characterize their temperature stability, leading to enhanced mechanical properties due to the relaxation of residual stresses before recrystallization and grain growth occurs. Such data gives imprtant information for minute design of microstructure and properties.
5:00 PM
Multicomponent Nanostructured Al-based High-performance Alloys for Elevated Temperature Structural Applications: Gourav Mundhra1; Hsin-Chieh Chao2; Ya-Jing Lee3; Jien-Wei Yeh3; B. S. Murty4; 1Indian Institute of Technology, National Tsing Hua University; 2MSS Corps. Co. LTD.; 3National Tsing Hua University; 4Indian Institute of Technology
The push for net-zero emissions in aviation motivate efforts to accelerate lightweight materials development. High-strength Al-based alloys widely used as aircraft construction material have abysmal softening resistance, which makes their application in aircraft engine components scanty. We propose a new design strategy to develop multicomponent Al-based alloys to overcome this bottleneck. We achieved explosive coherent nano-intermetallic formation in ductile FCC matrix via novel composition-design approach and rapid solidification processing technology. In-depth nanostructure characterization through S/TEM-EDS analysis revealed the presence of multicomponent nanoscale intermetallic compound. The designed nanostructured Al-based alloys had an optimum combination of high specific yield strength and high specific young’s modulus better than currently used aerospace alloys at room temperature and this is retained at extreme temperatures close to 72% of the melting point. Bending tests revealed that our ultra-strong alloys exhibit a ductile failure with a significantly high strain to fracture as compared to conventional Al-based alloys.