Compositional Design of Soft Magnetic High Entropy Alloys by Minimizing Magnetostriction Coefficient in (Fe0.3Co0.5Ni0.2)100−x(Al1/3Si2/3)x System

Developing cost-effective soft magnetic alloys with excellent mechanical properties is very important to energy-saving industries. This study investigated the magnetic and mechanical properties of a series of (Fe0.3Co0.5Ni0.2)100−x(Al1/3Si2/3)x high-entropy alloys (HEAs) (x = 0, 5, 10, 15, and 25) at room temperature. The Fe0.3Co0.5Ni0.2 base alloy composition was chosen since it has very the smallest saturation magnetostriction coefficient. It was found that the (Fe0.3Co0.5Ni0.2)95(Al1/3Si2/3)5 alloy maintains a simple face-centered cubic (FCC) solid solution structure in the states of as-cast, cold-rolled, and after annealing at 1000 °C. The alloy after annealing exhibits a tensile yield strength of 235 MPa, ultimate tensile strength of 572 MPa, an elongation of 38%, a saturation magnetization (Ms) of 1.49 T, and a coercivity of 96 A/m. The alloy not only demonstrates an optimal combination of soft magnetic and mechanical properties, it also shows advantages of easy fabrication and processing and high thermal stability over silicon steel and amorphous soft magnetic materials. Therefore, the alloy of (Fe0.3Co0.5Ni0.2)95(Al1/3Si2/3)5 holds good potential as next-generation soft magnets for wide-range industrial applications.

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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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Influence of Aluminum and Molybdenum on the Microstructure and Corrosion Behavior of Thermally Sprayed High-Entropy Alloy Coatings

Journal of Thermal Spray Technology ◽

10.1007/s11666-021-01297-6 ◽

2021 ◽

Author(s):

Martin Löbel ◽

Thomas Lindner ◽

Maximilian Grimm ◽

Lisa-Marie Rymer ◽

Thomas Lampke

Keyword(s):

Corrosion Resistance ◽

Protective Coatings ◽

Base Alloy ◽

Alloy System ◽

High Entropy Alloy ◽

Oxide Content ◽

Face Centered Cubic ◽

High Entropy ◽

Structural And Functional Properties ◽

Wide Range

AbstractHigh-entropy alloys (HEAs) have shown a wide range of promising structural and functional properties. By the application of coating technology, an economical exploitation can be achieved. The high wear and corrosion resistance of HEAs make them particularly interesting for the application as protective coatings. Especially for alloys with a high chromium content, a high corrosion resistance has been revealed. For the current investigations, the equimolar HEA CrFeCoNi with a single-phase face centered cubic structure is considered as a base alloy system. To increase the corrosion resistance as well as the hardness and strength, the influence of the alloying elements aluminum and molybdenum is analyzed. For the current investigations, the high kinetic process high-velocity oxygen fuel thermal spraying (HVOF) has been considered to produce coatings with a low porosity and oxide content. Feedstock is produced by inert gas atomization. The influence of the alloy composition on the microstructure, phase formation and resulting property profile is studied in detail. A detailed analysis of the corrosion resistance and underlying mechanisms is conducted. The pitting and passivation behavior are investigated by potentiodynamic polarization measurements in NaCl and H2SO4 electrolyte. A distinct improvement of the corrosion resistance can be achieved for the alloy Al0.3CrFeCoNiMo0.2.

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Effect of Interstitial Elements on the Cryogenic Mechanical Behavior of FCC High Entropy Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1016.1386 ◽

2021 ◽

Vol 1016 ◽

pp. 1386-1391

Author(s):

Anastasia Semenyuk ◽

Margarita Klimova ◽

Sergey Zherebtsov ◽

Nikita Stepanov

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

Thermomechanical Processing ◽

Induction Melting ◽

High Entropy Alloys ◽

Strengthening Effect ◽

Face Centered Cubic ◽

High Entropy ◽

C And N ◽

Interstitial Elements

High entropy alloys (HEAs) with face-centered cubic (fcc) structure, namely equiatomic CoCrFeMnNi alloy, have attracted considerable attention because of impressive cryogenic mechanical properties – strength, ductility, and fracture toughness. Further increase of the properties can be achieved, for example, by proper alloying. A particularly attractive option is the addition of interstitial elements like carbon or nitrogen. In present work, a series of CoCrFeMnNi-based alloys with different amounts of C and N (0-2 at.%) was prepared by induction melting. The alloys doped with C had lower Cr content to increase the solubility of carbon in the fcc solid solution. It was revealed that the solid solution strengthening effect of both C and N is significantly increased when the testing temperature decreases from 293K to 77K. The effect of thermomechanical processing on the structure and mechanical properties of the alloys is analyzed.

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The AC Soft Magnetic Properties of FeCoNixCuAl (1.0 ≤ x ≤ 1.75) High-Entropy Alloys

Materials ◽

10.3390/ma12244222 ◽

2019 ◽

Vol 12 (24) ◽

pp. 4222 ◽

Cited By ~ 2

Author(s):

Zhongyuan Wu ◽

Chenxu Wang ◽

Yin Zhang ◽

Xiaomeng Feng ◽

Yong Gu ◽

...

Keyword(s):

Magnetic Properties ◽

Soft Magnetic Materials ◽

Magnetic Flux Density ◽

High Entropy Alloys ◽

Soft Magnetic Properties ◽

Phase Content ◽

Soft Magnetic ◽

High Entropy ◽

Two Phases ◽

Fcc Phase

High-entropy alloys (HEAs) with soft magnetic properties are one of the new candidate soft magnetic materials which are usually used under an alternating current (AC) magnetic field. In this work, the AC soft magnetic properties are investigated for FeCoNixCuAl (1.0 ≤ x ≤ 1.75) HEAs. The X-ray diffraction (XRD) and scanning electron microscope (SEM) show that the alloy consists of two phases, namely a face-centred cubic (FCC) phase and a body-centred cubic (BCC) phase. With increasing Ni content, the FCC phase content increased. Further research shows that the AC soft magnetic properties of these alloys are closely related to their phase constitution. Increasing the FCC phase content contributes to a decrease in the values of AC remanence (AC Br), AC coercivity (AC Hc) and AC total loss (Ps), while it is harmful to the AC maximum magnetic flux density (AC Bm). Ps can be divided into two parts: AC hysteresis loss (Ph) and eddy current loss (Pe). With increasing frequency f, the ratio of Ph/Ps decreases for all samples. When f ≤ 150 Hz, Ph/Ps > 70%, which means that Ph mainly contributes to Ps. When f ≥ 800 Hz, Ph/Ps < 40% (except for the x = 1.0 sample), which means that Pe mainly contributes to Ps. At the same frequency, the ratio of Ph/Ps decreases gradually with increasing FCC phase content. The values of Pe and Ph are mainly related to the electrical resistivity (ρ) and the AC Hc, respectively. This provides a direction to reduce Ps.

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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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Microstructure and Mechanical Properties of FeNiCrCuAl High Entropy Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1036.101 ◽

2014 ◽

Vol 1036 ◽

pp. 101-105

Author(s):

Gheorghe Buluc ◽

Iulia Florea ◽

Oana Bălţătescu ◽

Costel Roman ◽

Ioan Carcea

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

High Hardness ◽

High Strength ◽

High Entropy Alloys ◽

Engineering Applications ◽

High Entropy ◽

Good Thermal Stability ◽

Microstructure And Mechanical Properties ◽

Wide Range

This paper presents the microstructure and the mechanical properties of FeNiCrCuAl high entropy alloys. The microstructure and mechanical properties of the annealed FeNiCrCuAl high entropy alloys were investigated using scanning electron microscopy, and X-ray diffraction. High entropy alloys have been known as a new type of materials and have been defined as having five or more principal elements, each one having a concentration between 5 and 35 at.%. Previous researches show that HEAs can be processed to form simple solid solution structures instead of intermetallics and other complicated compounds. This phenomenon is commonly attributed to the high configurational entropy in the solid solution state of HEAs. Furthermore, HEAs have also exhibited interesting properties such as high hardness and high strength, good thermal stability outstanding wear and oxidation resistance which offer great potential for engineering applications. The HEA systems explored in the past decade show that metallic elements are the most commonly used, e.g. Al, Cr, Fe, Co, Ni, Cu,Ti, etc. A wide range of HEAs exhibit high hardness, high strength, distinctive electrical and magnetic properties, high-temperature softening resistance, as well as favorable combination of compression strength and ductility. This combination of properties and the particular structures of HEAs are attractive for a number of potential engineering applications.

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Molecular Dynamics Study on the Diffusion Process of AuAgCuNiPd High-entropy Alloy Metallurgy Induced by Pulsed Laser Heating

Physical Chemistry Chemical Physics ◽

10.1039/d1cp02181h ◽

2021 ◽

Author(s):

Gen Lin ◽

Jianwu Guo ◽

Pengfei Ji

Keyword(s):

Mechanical Properties ◽

Molecular Dynamics ◽

Laser Heating ◽

Pulsed Laser ◽

High Entropy Alloy ◽

High Entropy Alloys ◽

High Entropy ◽

Alloy Material ◽

Wide Range ◽

Pulsed Laser Heating

As a novel alloy material with outstanding mechanical properties, high-entropy alloys have a wide range of promising applications. By establishing individual Au, Ag, Cu, Ni, and Pd nanolaminates with faced-centered-cubic...

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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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