Microstructure and Mechanical Properties of High-Entropy Alloys CoCrFeNiAl by Welding

Five common elements Co, Cr, Fe, Ni and Al were selected, and CoCrFeNiAl was prepared by arc-melting. The microstructure and mechanical properties after spot welding were studied. The results show that the cast microstructure of high entropy alloy CoCrFeNiAl is relatively uniform with a dendritic morphology. The heat is inversely proportional with the alloy grain sizes. The greater the heat is, the smaller the grain size is, which leads to the higher hardness and more uniform tissue. But there is a critical value of the heat(Hcrit) in spot welding. When Hactu(actual heat) exceeds Hcrit, it will adversely affect the performance, resulting in crack, splash and other defects.

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Microstructure and Mechanical Properties of VTaTiMoAlx Refractory High Entropy Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.898.638 ◽

2017 ◽

Vol 898 ◽

pp. 638-642 ◽

Cited By ~ 7

Author(s):

Dong Xu Qiao ◽

Hui Jiang ◽

Xiao Xue Chang ◽

Yi Ping Lu ◽

Ting Ju Li

Keyword(s):

Mechanical Properties ◽

Vacuum Arc ◽

High Entropy Alloys ◽

X Ray Diffraction ◽

Dendrite Structure ◽

X Ray ◽

High Entropy ◽

Arc Melting ◽

Vacuum Arc Melting ◽

Microstructure And Mechanical Properties

A series of refractory high-entropy alloys VTaTiMoAlx with x=0,0.2,0.6,1.0 were designed and produced by vacuum arc melting. The effect of added Al elements on the microstructure and mechanical properties of refractory high-entropy alloys were investigated. The X-ray diffraction results showed that all the high-entropy alloys consist of simple BCC solid solution. SEM indicated that the microstructure of VTaTiMoAlx changes from equiaxial dendritic-like structure to typical dendrite structure with the addition of Al element. The composition of different regions in the alloys are obtained by energy dispersive spectroscopy and shows that Ta, Mo elements are enriched in the dendrite areas, and Al, Ti, V are enriched in inter-dendrite areas. The yield strength and compress strain reach maximum (σ0.2=1221MPa, ε=9.91%) at x=0, and decrease with the addition of Al element at room temperature. Vickers hardness of the alloys improves as the Al addition.

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Microstructure and mechanical properties of RexNbMoTaW high-entropy alloys prepared by arc melting using metal powders

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2020.154301 ◽

2020 ◽

Vol 827 ◽

pp. 154301 ◽

Cited By ~ 6

Author(s):

Jian Zhang ◽

Yeyuan Hu ◽

Qinqin Wei ◽

Yuan Xiao ◽

Pingan Chen ◽

...

Keyword(s):

Mechanical Properties ◽

High Entropy Alloys ◽

Metal Powders ◽

High Entropy ◽

Arc Melting ◽

Microstructure And Mechanical Properties

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Effect of Mo Addition on The Microstructure and Mechanical Properties of CoCuFeNi High Entropy Alloy

Metals ◽

10.3390/met10081017 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1017

Author(s):

Yang Shao ◽

Huan Ma ◽

Yibing Wang

Keyword(s):

Mechanical Properties ◽

Solution Structure ◽

Tensile Tests ◽

Atomic Ratio ◽

Vacuum Arc ◽

High Entropy Alloy ◽

High Entropy Alloys ◽

High Entropy ◽

Microstructure And Mechanical Properties ◽

Mo Content

In order to reveal the effect of Mo addition on the microstructure and mechanical properties, (CoCuFeNi)100-xMox (x = 0, 10, 15, 19, and 25, x values in atomic ratio) high entropy alloys were prepared by vacuum arc-melting. The results showed that with Mo addition, the μ phase formed and serious separation occurred in the high entropy alloys. The content of μ phase increased with the increase in Mo content. The microstructure of the alloys changed from an initial single-phase face-center-cubic (FCC) solid solution structure (x = 0) to a hypoeutectic microstructure (x = 15), then to a full eutectic microstructure (x = 19), and finally to a hypereutectic microstructure (x = 25). Coherent interface between μ phase and FCC phase was observed. The (CoCuFeNi)81Mo19 alloy with fully eutectic microstructures exhibited the highest yield strength of 557 MPa and fracture strength of 767 MPa in tensile tests at room temperature. The fracture surface revealed that the formation of great amounts of the μ phase resulted in the loss of ductility of (CoCuFeNi)100-xMox alloys.

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Effects of Boron Content on microstructure and mechanical properties of AlFeCoNiBx High Entropy Alloy Prepared by vacuum arc melting

Vacuum ◽

10.1016/j.vacuum.2019.03.019 ◽

2019 ◽

Vol 164 ◽

pp. 212-218 ◽

Cited By ~ 10

Author(s):

Lili Hou ◽

Jiatao Hui ◽

Yuhong Yao ◽

Jian Chen ◽

Jiangnan Liu

Keyword(s):

Mechanical Properties ◽

Boron Content ◽

Vacuum Arc ◽

High Entropy Alloy ◽

High Entropy ◽

Arc Melting ◽

Vacuum Arc Melting ◽

Microstructure And Mechanical Properties

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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 Investigation of New Al10Cr12Mn28Fe(50-x)Ni(x) High Entropy Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.998.9 ◽

2020 ◽

Vol 998 ◽

pp. 9-14

Author(s):

Ahmed W. Abdel-Ghany ◽

Sally Elkatatny ◽

Mohamed Abdel Hady Gepreel

Keyword(s):

Mechanical Properties ◽

Yield Strength ◽

Compressive Yield Strength ◽

High Entropy Alloys ◽

High Ductility ◽

Cast Material ◽

High Entropy ◽

Arc Melting ◽

Microstructure And Mechanical Properties ◽

Cast Alloys

In the present study, two newly developed non-equiatomic high entropy Al10Cr12Mn28Fe(50-x)Ni(x) alloys (x= 20 & 15 at%, namely: Ni20 & Ni15, respectively) are investigated. The studied HEAs were designed based on thermodynamic principles to maintain high ductility and improve strength. Ingots were prepared using arc-melting then microstructure examinations and mechanical properties for the as-cast alloys were done. The mechanical properties were enhanced for the as-cast material, compared with previously introduced HEAs of the same system, namely Al5Cr12Mn28Fe35Ni20, (Al5) and Al10Cr12Mn23Fe35Ni20, (Al10). Al10Cr12Mn28Fe30Ni20 (Ni20) HEA generally shows the highest compressive yield strength which was improved by ∼7% when compared with previously introduced Al10.

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