Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.7
2.7
Journals
Entropy
Special Issues
Advances in High-Entropy Alloys
entropy-logo
Submit to Entropy Review for Entropy Propose a Special Issue

Journal Menu

► Journal Menu

Journal Browser

► Journal Browser
share announcement

Advances in High-Entropy Alloys

A special issue of Entropy (ISSN 1099-4300). This special issue belongs to the section "Multidisciplinary Applications".

Deadline for manuscript submissions: closed (22 February 2024) | Viewed by 9502

Special Issue Editor

Prof. Dr. Reza Abbaschian

E-Mail Website
Guest Editor
Distinguished Professor, Winston Chung Professor in Sustainability, Bourns College of Engineering, University of California, Riverside, CA 92521, USA
Interests: solidification and materials processing; interfacial kinetics; high-entropy alloys; mechanical properties; graphene growth; and high temperature-high pressure diamond growth

Special Issue Information

Dear Colleagues,

This Special Issue of Entropy (ISSN 1099-4300) will feature original and/or review articles focused on advances in high-entropy alloys (HEAs). Many of these alloy systems, which contain equimolar or near-equimolar multiple principal alloy components, exhibit high strength, wear and corrosion resistance, have significant potential for engineering applications. HEAs may contain single or multi-phase fcc, bcc, or hcp structures. Some of the alloys also show liquid phase separation (LPS) during high temperature melt processing. As such, their properties strongly depend not only on their compositions but also on the processing routes, such as solidification or powder processing.

This issue will cover topics including the influences of composition and processing, and the resultant structures, on the mechanical properties of HEAs. Understanding properties based on physical metallurgy principles, such as strengthening mechanisms, dislocations and strain hardening, ductility and hardness, solid solution hardening, twining and grain boundary effects, and multi-structural compositing affects would be of particular interest.

Prof. Dr. Reza Abbaschian
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Entropy is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • high-entropy alloys
  • multi-principal element alloys
  • processing
  • mechanical properties
  • strengthening
  • hardness
  • toughness

Published Papers (5 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

Jump to: Review

12 pages, 3237 KiB  
Article
Phase-Specific Damage Tolerance of a Eutectic High Entropy Alloy
by Shristy Jha, Rajiv S. Mishra and Sundeep Mukherjee
Entropy 2023, 25(12), 1604; https://doi.org/10.3390/e25121604 - 30 Nov 2023
Viewed by 877
Abstract
Phase-specific damage tolerance was investigated for the AlCoCrFeNi2.1 high entropy alloy with a lamellar microstructure of L12 and B2 phases. A microcantilever bending technique was utilized with notches milled in each of the two phases as well as at the phase [...] Read more.
Phase-specific damage tolerance was investigated for the AlCoCrFeNi2.1 high entropy alloy with a lamellar microstructure of L12 and B2 phases. A microcantilever bending technique was utilized with notches milled in each of the two phases as well as at the phase boundary. The L12 phase exhibited superior bending strength, strain hardening, and plastic deformation, while the B2 phase showed limited damage tolerance during bending due to micro-crack formation. The dimensionalized stiffness (DS) of the L12 phase cantilevers were relatively constant, indicating strain hardening followed by increase in stiffness at the later stages and, therefore, indicating plastic failure. In contrast, the B2 phase cantilevers showed a continuous drop in stiffness, indicating crack propagation. Distinct differences in micro-scale deformation mechanisms were reflected in post-compression fractography, with L12-phase cantilevers showing typical characteristics of ductile failure, including the activation of multiple slip planes, shear lips at the notch edge, and tearing inside the notch versus quasi-cleavage fracture with cleavage facets and a river pattern on the fracture surface for the B2-phase cantilevers. Full article
(This article belongs to the Special Issue Advances in High-Entropy Alloys)
►▼ Show Figures

Figure 1

14 pages, 8615 KiB  
Article
Molten Salt Corrosion Behavior of Dual-Phase High Entropy Alloy for Concentrating Solar Power Systems
by Kunjal Patel, Vahid Hasannaeimi, Maryam Sadeghilaridjani, Saideep Muskeri, Chaitanya Mahajan and Sundeep Mukherjee
Entropy 2023, 25(2), 296; https://doi.org/10.3390/e25020296 - 04 Feb 2023
Cited by 5 | Viewed by 1868
Abstract
Dual-phase high entropy alloys have recently attracted widespread attention as advanced structural materials due to their unique microstructure, excellent mechanical properties, and corrosion resistance. However, their molten salt corrosion behavior has not been reported, which is critical in evaluating their application merit in [...] Read more.
Dual-phase high entropy alloys have recently attracted widespread attention as advanced structural materials due to their unique microstructure, excellent mechanical properties, and corrosion resistance. However, their molten salt corrosion behavior has not been reported, which is critical in evaluating their application merit in the areas of concentrating solar power and nuclear energy. Here, the molten salt corrosion behavior of AlCoCrFeNi2.1 eutectic high-entropy alloy (EHEA) was evaluated in molten NaCl-KCl-MgCl2 salt at 450 °C and 650 °C in comparison to conventional duplex stainless steel 2205 (DS2205). The EHEA showed a significantly lower corrosion rate of ~1 mm/year at 450 °C compared to ~8 mm/year for DS2205. Similarly, EHEA showed a lower corrosion rate of ~9 mm/year at 650 °C compared to ~20 mm/year for DS2205. There was selective dissolution of the body-centered cubic phase in both the alloys, B2 in AlCoCrFeNi2.1 and α-Ferrite in DS2205. This was attributed to micro-galvanic coupling between the two phases in each alloy that was measured in terms of Volta potential difference using a scanning kelvin probe. Additionally, the work function increased with increasing temperature for AlCoCrFeNi2.1, indicating that the FCC-L12 phase acted as a barrier against further oxidation and protected the underlying BCC-B2 phase with enrichment of noble elements in the protective surface layer. Full article
(This article belongs to the Special Issue Advances in High-Entropy Alloys)
►▼ Show Figures

Figure 1

11 pages, 2507 KiB  
Article
Microstructure, Phase Evolution, and Chemical Behavior of CrCuFeNiTiAlx High Entropy Alloys Processed by Mechanical Alloying
by Anay del Ángel-González, Greysi D. Tapía-Higuera, Ibeth Rivera-Ortiz, José A. Castillo-Robles, José A. Rodríguez-García, Carlos A. Calles-Arriaga, José G. Miranda-Hernández and Enrique Rocha-Rangel
Entropy 2023, 25(2), 256; https://doi.org/10.3390/e25020256 - 31 Jan 2023
Cited by 3 | Viewed by 1320
Abstract
High entropy alloys (HEAs) of the type CrCuFeNiTi-Alx were processed through mechanical alloying. The aluminum concentration was varied in the alloy, to determine its effect on the HEAs’ microstructure, phase formation, and chemical behavior. X-ray diffraction studies performed on the pressureless sintered samples [...] Read more.
High entropy alloys (HEAs) of the type CrCuFeNiTi-Alx were processed through mechanical alloying. The aluminum concentration was varied in the alloy, to determine its effect on the HEAs’ microstructure, phase formation, and chemical behavior. X-ray diffraction studies performed on the pressureless sintered samples revealed the presence of structures composed of face centered cubic (FCC) and body centered cubic (BCC) solid-solution phases. Since the valences of the elements that form the alloy are different, a nearly stoichiometric compound was obtained, increasing the final entropy of the alloy. The aluminum was partly responsible for this situation, which also favored transforming part of the FCC phase into BCC phase on the sintered bodies. X-ray diffraction also indicated the formation of different compounds with the alloy’s metals. Bulk samples exhibited microstructures with different phases. The presence of these phases and the results of the chemical analyses revealed the formation of alloying elements that, in turn, formed a solid solution and, consequently, had a high entropy. From the corrosion tests, it could be concluded that the samples with a lower aluminum content were the most resistant to corrosion. Full article
(This article belongs to the Special Issue Advances in High-Entropy Alloys)
►▼ Show Figures

Figure 1

16 pages, 10080 KiB  
Article
Modeling Oxidation of AlCoCrFeNi High-Entropy Alloy Using Stochastic Cellular Automata
by Indranil Roy, Pratik K. Ray and Ganesh Balasubramanian
Entropy 2022, 24(9), 1263; https://doi.org/10.3390/e24091263 - 08 Sep 2022
Cited by 2 | Viewed by 1685
Abstract
Together with the thermodynamics and kinetics, the complex microstructure of high-entropy alloys (HEAs) exerts a significant influence on the associated oxidation mechanisms in these concentrated solid solutions. To describe the surface oxidation in AlCoCrFeNi HEA, we employed a stochastic cellular automata model that [...] Read more.
Together with the thermodynamics and kinetics, the complex microstructure of high-entropy alloys (HEAs) exerts a significant influence on the associated oxidation mechanisms in these concentrated solid solutions. To describe the surface oxidation in AlCoCrFeNi HEA, we employed a stochastic cellular automata model that replicates the mesoscale structures that form. The model benefits from diffusion coefficients of the principal elements through the native oxides predicted by using molecular simulations. Through our examination of the oxidation behavior as a function of the alloy composition, we corroborated that the oxide scale growth is a function of the complex chemistry and resultant microstructures. The effect of heat treatment on these alloys is also simulated by using reconstructed experimental micrographs. When they are in a single-crystal structure, no segregation is noted for α-Al2O3 and Cr2O3, which are the primary scale-forming oxides. However, a coexistent separation between Al2O3 and Cr2O3 oxide scales with the Al-Ni- and Cr-Fe-rich regions is predicted when phase-separated microstructures are incorporated into the model. Full article
(This article belongs to the Special Issue Advances in High-Entropy Alloys)
►▼ Show Figures

Figure 1

Review

Jump to: Research

30 pages, 5045 KiB  
Review
Review of Novel High-Entropy Protective Materials: Wear, Irradiation, and Erosion Resistance Properties
by Ana C. Feltrin, Qiuwei Xing, Akeem Damilola Akinwekomi, Owais Ahmed Waseem and Farid Akhtar
Entropy 2023, 25(1), 73; https://doi.org/10.3390/e25010073 - 30 Dec 2022
Cited by 8 | Viewed by 3191
Abstract
By their unique compositions and microstructures, recently developed high-entropy materials (HEMs) exhibit outstanding properties and performance above the threshold of traditional materials. Wear- and erosion-resistant materials are of significant interest for different applications, such as industrial devices, aerospace materials, and military equipment, related [...] Read more.
By their unique compositions and microstructures, recently developed high-entropy materials (HEMs) exhibit outstanding properties and performance above the threshold of traditional materials. Wear- and erosion-resistant materials are of significant interest for different applications, such as industrial devices, aerospace materials, and military equipment, related to their capability to tolerate heavy loads during sliding, rolling, or impact events. The high-entropy effect and crystal lattice distortion are attributed to higher hardness and yield stress, promoting increased wear and erosion resistance in HEMs. In addition, HEMs have higher defect formation/migration energies that inhibit the formation of defect clusters, making them resistant to structural damage after radiation. Hence, they are sought after in the nuclear and aerospace industries. The concept of high-entropy, applied to protective materials, has enhanced the properties and performance of HEMs. Therefore, they are viable candidates for today’s demanding protective materials for wear, erosion, and irradiation applications. Full article
(This article belongs to the Special Issue Advances in High-Entropy Alloys)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-5
Back to TopTop