Alloying, thermal stability and strengthening in spark plasma sintered AlxCoCrCuFeNi high entropy alloys

The microstructure, phase formation, thermal stability and soft magnetic properties of melt-spun high entropy alloys (HEAs) Fe27Co27Ni27Si10−xB9Lax with various La substitutions for Si (x = 0, 0.2, 0.4, 0.6, 0.8, and 1) were investigated in this work. The Fe27Co27Ni27Si10−xB9La0.6 alloy shows superior soft magnetic properties with low coercivity Hc of ~7.1 A/m and high saturation magnetization Bs of 1.07 T. The content of La has an important effect on the primary crystallization temperature (Tx1) and the secondary crystallization temperature (Tx2) of the alloys. After annealing at relatively low temperature, the saturation magnetization of the alloy increases and the microstructure with a small amount of body-centered cubic (BCC) phase embedded in amorphous matrix is observed. Increasing the annealing temperature reduces the magnetization due to the transformation of BCC phase into face-centered cubic (FCC) phase.

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Phase Evolution and Mechanical Properties of AlCoCrFeNiSix High-Entropy Alloys Synthesized by Mechanical Alloying and Spark Plasma Sintering

Journal of Materials Engineering and Performance ◽

10.1007/s11665-018-3409-4 ◽

2018 ◽

Vol 27 (7) ◽

pp. 3304-3314 ◽

Cited By ~ 14

Author(s):

Anil Kumar ◽

Akhilesh Kumar Swarnakar ◽

Manoj Chopkar

Keyword(s):

Mechanical Properties ◽

Mechanical Alloying ◽

Spark Plasma Sintering ◽

Phase Evolution ◽

High Entropy Alloys ◽

High Entropy ◽

Plasma Sintering ◽

Spark Plasma

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Effect of Fe on microstructure, phase evolution and mechanical properties of (AlCoCrFeNi)100-xFex high entropy alloys processed by spark plasma sintering

Intermetallics ◽

10.1016/j.intermet.2018.09.011 ◽

2018 ◽

Vol 103 ◽

pp. 1-11 ◽

Cited By ~ 9

Author(s):

Lin Guo ◽

Daihong Xiao ◽

Wenqian Wu ◽

Song Ni ◽

Min Song

Keyword(s):

Mechanical Properties ◽

Spark Plasma Sintering ◽

Phase Evolution ◽

High Entropy Alloys ◽

High Entropy ◽

Plasma Sintering ◽

Spark Plasma

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Refractory TaTiNb, TaTiNbZr, and TaTiNbZrX (X = Mo, W) high entropy alloys by combined use of high energy ball milling and spark plasma sintering: Structural characterization, mechanical properties, electrical resistivity, and thermal conductivity

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2021.162030 ◽

2021 ◽

pp. 162030

Author(s):

N.F. Shkodich ◽

K.V. Kuskov ◽

A.S. Sedegov ◽

I.D. Kovalev ◽

A.V. Panteleeva ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Electrical Resistivity ◽

High Energy ◽

High Entropy Alloys ◽

High Entropy ◽

Plasma Sintering ◽

Combined Use ◽

Spark Plasma ◽

Energy Ball

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Compression stress strengthening modelling of a ultrafine-grained equiatomic SPS CoCrFeNiNb high-entropy alloy

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220943245 ◽

2020 ◽

pp. 095440622094324

Author(s):

Marcello Cabibbo ◽

Filip Průša ◽

Alexandra Šenková ◽

Andrea Školáková ◽

Vojtěch Kučera ◽

...

Keyword(s):

Powder Metallurgy ◽

Mechanical Alloying ◽

Oxide Phase ◽

High Entropy Alloy ◽

Induction Melting ◽

High Entropy Alloys ◽

High Entropy ◽

Plasma Sintering ◽

Transmission Electron ◽

Spark Plasma

High-entropy alloys are known to show exceptionally high mechanical properties, both compression and tensile strength, and unique physical properties, such as their phase stability. These quite unusual properties are primarily due to the microstructure generated by mechanical alloying processes, such as conventional induction arc melting, powder metallurgy, or mechanical alloying. In the present study, an equiatomic CoCrFeNiNb high-entropy alloy was prepared by a sequence of conventional induction melting, powder metallurgy, and compaction via spark plasma sintering. The high-entropy alloys showed uniform sub-micrometer grain microstructure consisted by a mixture of an fcc solid solution strengthened by a hcp Laves phase and a third intergranular oxide phase. The as-cast high-entropy alloys showed an ultimate compression strength (UCS) of ∼1400 MPa, which after sintering and compaction at 1273 K increased up to ∼2400 MPa. Extensive transmission electron microscopy quantitative analyses were carried out to model the UCS. A quite good agreement between the microstructure-strengthening model and the experimental UCS was found.

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