High Entropy Materials: Concentrated Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond III: Materials Discovery and Design
Sponsored by: TMS: Nanomaterials Committee
Program Organizers: Yu Zhong, Worcester Polytechnic Institute; Michael Gao, National Energy Technology Laboratory; Xingbo Liu, West Virginia University; Peter Liaw, University of Tennessee; Jian Luo, University of California, San Diego; Yiquan Wu, Alfred University; Mitra Taheri, Johns Hopkins University; Amy Clarke, Los Alamos National Laboratory
Tuesday 8:00 AM
October 11, 2022
Room: 324
Location: David L. Lawrence Convention Center
Session Chair: Bai Cui, University of Nebraska-Lincoln; Kun Wang, Alfred University
8:00 AM Keynote
High Entropy Alloys and NSF: Jonathan Madison1; 1National Science Foundation
Within the National Science Foundations’ Division of Materials Research, studies on High Entropy Materials remains an important topic and a strategic emphasis area for its Metals and Metallic Nanostructures Program (MMN). This talk will showcase a few exemplary research activities on High Entropy Alloys, as funded by MMN, from both the past and recent history. The funding mechanisms used to sustain these notable efforts will also be highlighted. Additionally, current, and emerging funding opportunities along with their requirements, application windows and focus areas will also be shared. Lastly, broader perspectives on NSF working groups and the Directorate for Technology, Innovation and Partnerships will be presented toward a discussion of advancing the community’s ability to realize the promise and potential of the Materials Genome Initiative.
8:30 AM Invited
Design of Multicomponent Rare-earth Sesquioxides for Thermal/Environmental Barrier Coatings: Kristyn Ardrey1; Mahboobe Jassas1; Mukil Ayyasamy1; Kang Wang1; Kevin Reuwer2; Jonathan Laurer3; Carolina Tallon2; Bi-Cheng Zhou1; Prasanna Balachandran1; Patrick Hopkins1; Elizabeth Opila1; 1University of Virginia; 2Virginia Tech; 3Commonwealth Center for Advanced Manufacturing
Refractory alloys, such as Nb-base C-103, are susceptible to rapid oxidation thereby requiring environmental barrier coatings (EBCs). New coating concepts utilize “high entropy” rare-earth oxide (HERO) mixtures to achieve requisite coating properties, as follows. Cubic phase rare earth (RE) sesquioxides (RE2O3) are desired for a good thermal expansion match to C-103. RE2O3 are high-temperature steam stable. Large RE cations readily form apatite barrier layers during reaction with molten calcium magnesium aluminosilicates, common contaminants in turbine engines. Oxygen diffusivity in Y2O3 is orders of magnitude lower than that in yttria stabilized zirconia. Combinations of RE cations in RE2O3 with large mass and size variation reduce thermal conductivity due to increased phonon scattering. Nb and RE2O3 have a stable interface due to the significantly higher stability of RE2O3 relative to Nb-oxides. RE2O3 mixtures synthesized by slurry or atmospheric plasma spray that simultaneously optimize EBC properties for refractory alloys will be described.
9:00 AM
Accelerated Discovery of Refractory High Entropy Materials by Machine Learning and High Throughput Experiments: Kun Wang1; Yonggang Yan1; 1Alfred University
Refractory high entropy materials (RHEMs), including refractory alloys and ultrahigh temperature ceramics, have exhibited excellent properties as potential high-temperature structural materials in extreme environments such as nuclear reactors and hypersonic environments etc. However, it would be extremely challenging to develop such materials using the conventional trial and error experiment due to the massive compositional space. Herein, we employed machine learning (ML) to rapidly and accurately screen the compositions of RHEMs with desirable properties. In particular, the high-throughput experiments were employed to generate high-quality dataset for ML training, because the experiment was conducted under the same conditions and by the same researcher. The experimental validation is performed to examine the performance of the ML model. In addition, the ML is also applied to discover the most relevant input features with respect to the output properties, giving rise to an inverse understanding of the underlying physical mechanisms.
9:20 AM
An Experimentally Driven High-throughput Approach to Design Refractory High-entropy Alloys: Chanho Lee1; Dongyue Xie1; Benjamin Derby1; Jon Baldwin1; Christopher Tandoc2; Osman Atwani1; Yong-Jie Hu2; Nan Li1; Saryu Fensin1; 1Los Alamos National Laboratory; 2Drexel University
High-entropy alloy (HEA) design strategies have been limited to theoretical/computational approaches due to their compositional complexity and extremely large compositional parameter space. In this work, we developed an experimentally driven, high-throughput, HEA design approach using a physical vapor deposition (PVD) technique and coupled it with nanomechanical testing to accelerate material design for structural applications. The PVD technique enabled the formation of a compositional gradient across a thin-film sample. Specifically, a 10 cm wafer was used to manufacture a continuous set of 80 HEA compositions within the Nb-Ti-V-Zr family using a single deposition cycle. By applying the solid-solution strengthening theory and developed machine-learning approaches, the strength and ductility of these HEA compositions were quantitatively determined/predicted and then experimentally verified by nano-indentation hardness test. Consequently, 7 refractory HEA compositions were successfully down-selected based on optimized strength and ductility predictions.
9:40 AM
Development of Ni-based Medium Entropy Alloys Using THERMOCALC Software: Elyorjon Jumaev1; Amir Abidov1; Ulugbek Ruziev1; Ki Buem Kim2; 1Almalyk Mining and Metallurgical Combine JSC; 2Sejong University
The Ni-based Ni48(CrAlFe)15Ti7 and Ni48(CrCuFe)12.5Al7.5Ti7 medium entropy alloys were designed by Thermocalc software and fabricated using arc suction casting method by having Ti-guttered in an argon atmosphere. The effect of the Cu element on phase evolution, microstructure, and mechanical characteristics was investigated. Detailed characterization reveals that the alloys exhibit dual microstructures consisting of BCC dendrite and FCC interdendritic in Ni48(CrAlFe)15Ti7 alloy while exhibiting rectangular shape morphology (γ + γ՛ phases) in Cu addition Ni48(CrCuFe)12.5Al7.5Ti7 alloy. The result of the mechanical property test illustrates that the alloys present outstanding strength in the high-temperature range compared to Inconel 713C and excellent ductility with the microstructure of γ + γ՛ phases.
10:00 AM Break
10:20 AM Cancelled
Computationally Guided Design of FCC-based High Entropy Alloys: Kenneth Smith1; John Sharon1; Ryan Deacon1; Soumalya Sarkar1; Michael Gao2; 1Raytheon Technologies Research Center; 2National Energy Technology Laboratory
With multiple principal elements in solution, high entropy alloys (HEA) open a new space containing billions of new compositions. This new and vast composition space enables the ability to identify and tailor potential HEA alternatives to current solid solution strengthened nickel superalloys. We used a computational materials design process that couples machine learning, CALPHAD, and analytical models to identify FCC alloy candidates. A series of different objectives and constraints applied to guide selection of the alloy candidates. Selected candidate alloys were fabricated and subjected to thermal and mechanical testing along with characterizing the thermally grown oxide. In this presentation we will describe how we use coupled computational and experimental methods to identify and characterize HEA candidates that further accelerates materials discovery.
10:40 AM Invited
High-Entropy Carbide Ceramics: Transformative Materials for Extreme Environments: Bai Cui1; Fei Wang1; Xueliang Yan1; Yongfeng Lu1; 1University of Nebraska-Lincoln
The concept of entropy stabilization has created promising opportunities for the design of new ceramic materials for extreme environments encountered in advanced nuclear reactors and gas turbines. High-entropy carbide ceramics (HECCs) are characterized by multiple metal elements in an equal or near-equal atomic ratio in the cation position but forms a stable single-phase lattice structure. The compositional complexity in HECCs can induce the atomic-level disorder, significant lattice distortion, and unique physical properties such as higher hardness, lower thermal conductivity, and improved oxidation resistance than the binary transition metal carbides. Since 2018, our team has developed a spark plasma sintering process for the synthesis of single-phase HECCs, reported their thermal and mechanical properties, and investigated their irradiation damage resistance for the first time. This talk will focus on our experimental research activities to reveal fundamental mechanisms governing the processing-microstructure-property relationship in these novel materials.
11:00 AM
Effect of Short-range Ordering on Diffusion Properties in Complex Concentrated Alloys: Anus Manzoor1; Yongfeng Zhang1; 1University of Wisconsin-Madison
Diffusion properties are in general important for kinetic processes in complex concentrated alloys (CCAs). In CCAs, short-range ordering (SRO) may exist particularly at lower temperatures which is caused by the mixing of different constituent elements. Short-range ordering can significantly affect diffusion properties in CCAs and thus, it is critical to understand the impact of SRO on defect mediated diffusion. In this work, using atomistic calculations, we have shown that the diffusion can be localized in the SRO state of a given alloy. By elucidating the role of vacancy formation and migration energy, we have shown that the localization of diffusion is mainly controlled by the vacancy formation energy. Furthermore, the SRO can impact probability distribution of the vacancy formation energy and which ultimately affects equilibrium concentration of vacancies.
11:20 AM
Hardness of Thin Film High Entropy Transition Metal Ceramics: Nathaniel McIlwaine1; 1Penn State University
Group 4-6B transition metal carbides, nitrides, and borides possess favorable refractory properties such as high hardness and high melting temperatures, which are useful for advanced armor, cutting tools, and spacecraft thermal protection systems. High entropy transition metal ceramics (TMCs) are single phase, multicomponent materials that have a high degree of configurational entropy on lattice sites, which can result in enhanced thermal and mechanical properties compared to binary TMCs. Physical vapor deposition of thin films through magnetron sputtering provides the ability to kinetically freeze-in atomic arrangements with a high degree of configurational disorder on both cation and anion sites. This opens up the composition space for an investigation into carbo-boro-nitrides. This research investigates the ability to maximize hardness of thin film, high entropy TMCs by inducing local internal strains in the rocksalt crystal structure through the tailoring of chemical composition.
11:40 AM
High-throughput Design of High-performance Lightweight High-entropy Alloys: Rui Feng1; Chuan Zhang2; Michael Gao3; Zongrui Pei3; Fan Zhang2; Yan Chen1; Dong Ma4; Ke An1; Jonathan Poplawsky1; Lizhi Ouyang5; Yang Ren6; Jeffrey Hawk3; Michael Widom7; Peter Liaw7; 1Oak Ridge National Laboratory; 2Computherm, LLC; 3National Energy Technology Laboratory; 4Songshan Lake Materials Laboratory; 5Tennessee State University; 6Argonne National Laboratory; 7Carnegie Mellon University
Developing affordable and light high-temperature materials alternative to Ni-base superalloys has significantly increased the efforts in designing advanced ferritic superalloys. However, currently developed ferritic superalloys still exhibit low high-temperature strengths, which limits their usage. Here we use a CALPHAD-based high-throughput computational method to design light, strong, and low-cost high-entropy alloys for elevated-temperature applications. Through the high-throughput screening, precipitation-strengthened lightweight high-entropy alloys are discovered from thousands of initial compositions, which exhibit enhanced strengths, compared to other counterparts at room and elevated temperatures. The experimental and theoretical understanding of both successful and failed cases in their strengthening mechanisms and order-disorder transitions further improves the accuracy of the thermodynamic database of the discovered alloy system. This study shows that integrating high-throughput screening, multiscale modeling, and experimental validation prove to be efficient and useful in accelerating the discovery of advanced precipitation-strengthened structural materials tuned by the high-entropy alloy concept.