Development of Novel Lightweight Al-Rich Quinary Medium-Entropy Alloys with High Strength and Ductility

Most high-entropy alloys and medium-entropy alloys (MEAs) possess outstanding mechanical properties. In this study, a series of lightweight nonequiatomic Al50–Ti–Cr–Mn–V MEAs with a dual phase were produced through arc melting and drop casting. These cast alloys were composed of body-centered cubic and face-centered cubic phases. The density of all investigated MEAs was less than 5 g/cm3 in order to meet energy and transportation industry requirements. The effect of each element on the microstructure evolution and mechanical properties of these MEAs was investigated. All the MEAs demonstrated outstanding compressive strength, with no fractures observed after a compressive strain of 20%. Following the fine-tuning of the alloy composition, the Al50Ti20Cr10Mn15V5 MEA exhibited the most compressive strength (~1800 MPa) and ductility (~34%). A significant improvement in the mechanical compressive properties was achieved (strength of ~2000 MPa, strain of ~40%) after annealing (at 1000 °C for 0.5 h) and oil-quenching. With its extremely high specific compressive strength (452 MPa·g/cm3) and ductility, the lightweight Al50Ti20Cr10Mn15V5 MEA demonstrates good potential for energy or transportation applications in the future.

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Effects of Different Contents of Each Component on the Structural Stability and Mechanical Properties of Co-Cr-Fe-Ni High-Entropy Alloys

Applied Sciences ◽

10.3390/app11062832 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2832

Author(s):

Haibo Liu ◽

Cunlin Xin ◽

Lei Liu ◽

Chunqiang Zhuang

Keyword(s):

Mechanical Properties ◽

Structural Stability ◽

High Entropy Alloys ◽

Face Centered Cubic ◽

Obvious Effect ◽

High Entropy ◽

Precise Control ◽

Component Content ◽

Face Centered ◽

And Performance

The structural stability of high-entropy alloys (HEAs) is closely related to their mechanical properties. The precise control of the component content is a key step toward understanding their structural stability and further determining their mechanical properties. In this study, first-principle calculations were performed to investigate the effects of different contents of each component on the structural stability and mechanical properties of Co-Cr-Fe-Ni HEAs based on the supercell model. Co-Cr-Fe-Ni HEAs were constructed based on a single face-centered cubic (FCC) solid solution. Elemental components have a clear effect on their structure and performance; the Cr and Fe elements have an obvious effect on the structural stability and equilibrium lattice constant, respectively. The Ni elements have an obvious effect on stiffness. The Pugh ratios indicate that Cr and Ni addition may increase ductility, whereas Co and Fe addition may decrease it. With increasing Co and Fe contents or decreasing Cr and Ni contents, the structural stability and stiffness of Co-Cr-Fe-Ni HEAs are improved. The structural stability and mechanical properties may be related to the strength of the metallic bonding and covalent bonding inside Co-Cr-Fe-Ni HEAs, which, in turn, is determined by the change in element content. Our results provide the underlying insights needed to guide the optimization of Co-Cr-Fe-Ni HEAs with excellent mechanical properties.

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Effect of Molybdenum Additives on Corrosion Behavior of (CoCrFeNi)100−xMox High-Entropy Alloys

Entropy ◽

10.3390/e20120908 ◽

2018 ◽

Vol 20 (12) ◽

pp. 908 ◽

Cited By ~ 9

Author(s):

Wenrui Wang ◽

Jieqian Wang ◽

Honggang Yi ◽

Wu Qi ◽

Qing Peng

Keyword(s):

Corrosion Behavior ◽

Compressive Strain ◽

Compressive Yield Strength ◽

High Entropy Alloys ◽

Face Centered Cubic ◽

Σ Phase ◽

High Entropy ◽

Passivation Film ◽

Face Centered ◽

Mo Content

The present work investigates the influence of micro-alloyed Mo on the corrosion behavior of (CoCrFeNi)100−xMox high-entropy alloys. All of the (CoCrFeNi)100−xMox alloys exhibit a single face-centered cubic (FCC) solid solution. However, the (CoCrFeNi)97Mo3 alloy exhibits an ordered sigma (σ) phase enriched in Cr and Mo. With the increase of x (the Mo content) from 1 to 3, the hardness of the (CoCrFeNi)100−xMox alloys increases from 124.8 to 133.6 Vickers hardness (HV), and the compressive yield strength increases from 113.6 MPa to 141.1 MPa, without fracture under about a 60% compressive strain. The potentiodynamic polarization curve in a 3.5% NaCl solution indicates that the addition of Mo has a beneficial effect on the corrosion resistance to some certain extent, opposed to the σ phase. Furthermore, the alloys tend to form a passivation film in the 0.5 M H2SO4 solution in order to inhibit the progress of the corrosion reaction as the Mo content increases.

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Influence of Ti on the Tensile Properties of the High-Strength Powder Metallurgy High Entropy Alloys

Materials ◽

10.3390/ma13030578 ◽

2020 ◽

Vol 13 (3) ◽

pp. 578 ◽

Cited By ~ 3

Author(s):

Igor Moravcik ◽

Stepan Gamanov ◽

Larissa Moravcikova-Gouvea ◽

Zuzana Kovacova ◽

Michael Kitzmantel ◽

...

Keyword(s):

Powder Metallurgy ◽

Tensile Properties ◽

High Strength ◽

High Entropy Alloys ◽

Face Centered Cubic ◽

High Entropy ◽

Solid Solution Strengthening ◽

Plasma Sintering ◽

Annealing Heat Treatment ◽

Face Centered

The focus of this study is the evaluation of the influence of Ti concentration on the tensile properties of powder metallurgy high entropy alloys. Three Ni1.5Co1.5CrFeTiX alloys with X = 0.3; 0.5 and 0.7 were produced by mechanical alloying and spark plasma sintering. Additional annealing heat treatment at 1100 °C was utilized to obtain homogenous single-phase face centered cubic (FCC) microstructures, with minor oxide inclusions. The results show that Ti increases the strength of the alloys by increasing the average atomic size misfit i.e., solid solution strengthening. An excellent combination of mechanical properties can be obtained by the proposed method. For instance, annealed Ni1,5Co1,5CrFeTi0.7 alloy possessed the ultimate tensile strength as high as ~1600 MPa at a tensile ductility of ~9%, despite the oxide contamination. The presented results may serve as a guideline for future alloy design of novel, inclusion-tolerant materials for sustainable metallurgy.

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Mechanical properties of high-entropy alloys with emphasis on face-centered cubic alloys

Progress in Materials Science ◽

10.1016/j.pmatsci.2018.12.003 ◽

2019 ◽

Vol 102 ◽

pp. 296-345 ◽

Cited By ~ 114

Author(s):

Zezhou Li ◽

Shiteng Zhao ◽

Robert O. Ritchie ◽

Marc A. Meyers

Keyword(s):

Mechanical Properties ◽

High Entropy Alloys ◽

Face Centered Cubic ◽

High Entropy ◽

Face Centered

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Microstructure and Mechanical Properties of the W-Ni-Co System Refractory High-Entropy Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.816.324 ◽

2015 ◽

Vol 816 ◽

pp. 324-329 ◽

Cited By ~ 3

Author(s):

Hui Jiang ◽

Li Jiang ◽

Yi Ping Lu ◽

Tong Min Wang ◽

Zhi Qiang Cao ◽

...

Keyword(s):

Mechanical Properties ◽

Vacuum Arc ◽

High Entropy Alloys ◽

Face Centered Cubic ◽

High Entropy ◽

Melting Temperatures ◽

Arc Melting ◽

Microstructure And Mechanical Properties ◽

The Matrix ◽

Face Centered

The elements Mo, Cr and V were added to the W-Ni-Co system high entropy alloys, the effects of these added elements on microstructure and mechanical properties of these alloys were studied. The alloys were produced by vacuum arc melting. The compositions were W0.5Ni2Co2VMo0.5,W0.5Ni2Co2VCr0.5and W0.5Ni2Co2CrMo0.5(denoted as Alloy 1, Alloy 2 and Alloy 3) respectively. The theoretical melting temperatures were higher than 2000 K. X-ray diffraction, SEM and energy dispersive spectroscopy (EDS) results indicated that the matrix of the alloys is face-centered cubic (FCC) solid-solution, the alloys showed dendrite crystal structure. Ni, Co elements were enriched in the dendrite areas, the W, Mo were enriched in the inter-dendrite regions ,while V, Cr elements were uniform distribution. The Vickers hardness of these alloys was 376.1 HV, 255.88 HV and 306.8 HV, respectively. The yield strength values (σ0.2) of Alloy 1, Alloy 2 and Alloy 3 were approximately 1000MPa, 750MPa, 250MPa, respectively. The alloys show good compression plasticity deformation capacity at RT.

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Synergetic effect of Si addition on mechanical properties in face-centered-cubic high entropy alloys: A first-principles study

Modelling and Simulation in Materials Science and Engineering ◽

10.1088/1361-651x/ac455a ◽

2021 ◽

Author(s):

T Tsuru ◽

Ivan Lobzenko ◽

Daixiu Wei

Keyword(s):

Mechanical Properties ◽

First Principles ◽

Stacking Fault ◽

High Entropy Alloys ◽

Face Centered Cubic ◽

High Entropy ◽

Si Doped ◽

Face Centered ◽

Si Addition ◽

Strength And Ductility

Abstract High-entropy alloys (HEA) have been receiving increased attention for their excellent mechanical properties. Our recent study revealed that Si-doped face-centered cubic (FCC) HEAs have great potential to improve both strength and ductility. Here, we carried out first-principles calculations in cooperation with Monte Carlo simulation and structural factor analysis to explore the effect of Si addition on the macroscopic mechanical properties. As a result, Si addition increased the local lattice distortion and the stacking fault energy. Furthermore, the short-range order formation in Si-doped alloy caused highly fluctuated stacking fault energy. Thus, the heterogeneous solid solution states in which low and high stacking fault regions are distributed into the matrix were nucleated. This unique feature in Si-doped FCC-HEA induces ultrafine twin formation in Si-doped alloys, which can be a dominant factor in improving both strength and ductility.

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L21-strengthened face-centered cubic high-entropy alloy with high strength and ductility

Materials Science and Engineering A ◽

10.1016/j.msea.2020.140056 ◽

2020 ◽

Vol 797 ◽

pp. 140056 ◽

Cited By ~ 2

Author(s):

Yongliang Qi ◽

Yake Wu ◽

Tinghui Cao ◽

Lin He ◽

Feng Jiang ◽

...

Keyword(s):

High Strength ◽

High Entropy Alloy ◽

Face Centered Cubic ◽

High Entropy ◽

Face Centered ◽

Strength And Ductility

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Achievable Strength of Nanostructured Composites with Co-Deformable Components

Materials Science Forum ◽

10.4028/www.scientific.net/msf.683.243 ◽

2011 ◽

Vol 683 ◽

pp. 243-247 ◽

Cited By ~ 1

Author(s):

Ke Han ◽

Jing Ping Chen

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

High Strength ◽

Face Centered Cubic ◽

Body Centered Cubic ◽

Bulk Materials ◽

Nanostructured Composites ◽

Sheet Products ◽

Face Centered ◽

Strengthening Phases

Large amount of research has been undertaken on the effects of conventional thermomechanical treatment and chemistry variations on the mechanical properties of nanostructured bulk materials developed for wire rod and sheet products. The thermomechanical treatments are selected to refine as much as possible the microstructure to achieve high strength. In most of the cases, the alloy additions are deliberated added to be beneficial to the mechanical properties of the nanostructured materials, especially the tensile strength. In addition to refine the microstructure, both the thermomechanical treatments and chemistry variations may also alter the shape and distribution of the strengthening phases. This article describes the nanostructured composites with face-centered cubic (fcc) copper or body-centered cubic (bcc) ferrite as matrix and discusses several factors that affect the mechanical strength of such materials.

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