•Co25.4Cr15Fe37.9Mn3.5Ni16.8Si1.4 alloy was produced by wire arc additive technology.•The microstructure consists mainly of FCC phase but also has CoCr nano phase.•The alloy has good mechanical ...properties.•The chemical are distributed homogeneously.
This study employed wire arc additive manufacturing (WAAM) to fabricate non-equiatomic Co25.4Cr15Fe37.9Mn3.5Ni16.8Si1.4 high-entropy alloy (HEA). Microstructure, elemental distribution, and mechanical properties were investigated. The fabricated HEA has a dendrite structure composed mainly of the FCC phase and CoCr nanoparticles with 1.5–2.5 nm sizes. Energy-dispersive X-ray spectrometry analysis showed that elements are distributed homogeneously in the alloy. Transmission electron microscopy demonstrated the presence of randomly oriented residual dislocations with the density of 1.2∙1010 cm−2. Compressive and tensile tests showed ductile deformation behavior. The yield strength of the alloy is ∼ 279 MPa; ultimate tensile strength is ∼ 500 MPa, and elongation is ∼ 63%.
•Al2.1Co0.3Cr0.5FeNi2.1 high entropy alloy was obtained by additive manufacturing.•The microstructure consists of dendrite grains and interdendrite areas.•The key phases detected at the submicro-and ...nano-levels are Al3Ni and (Ni, Co)3Al4.•Content of Al and Ni atoms are prevalent above other elements in the alloy.
The Al2.1Co0.3Cr0.5FeNi2.1 high-entropy alloy was a product of wire arc additive manufacturing. The feeding material was a three-core cable with different element compositions: Al – 99.95%; Cr – 20%, Ni – 80%; Co – 17%, Fe – 54%, Ni – 29%. Optical microscopy techniques were applied to study the microstructure of the produced material, which comprised dendrite grains varying from 4 to 15 µm and interdendritic regions. Scanning electron microscopy demonstrated the dendrite grains were generally made of Al and Ni atoms; the interdendritic regions contained Cr and Fe, whereas Co was distributed quasi-homogenously in the material. Transmission electron microscopy detected main phases to be Al3Ni and (Ni, Co)3Al4. An Al3Ni phase is cubic, and a (Ni, Co)3Al4 phase is spherical. 7 to 10 nm (Ni, Co)3Al4 particles were found along the boundaries of submicron (40–100 nm) Al3Ni phases.
Using wire-arc additive manufacturing (WAAM), we produced samples of Al–Co–Cr–Fe–Ni high-entropy alloy (HEA) with a grain size of 4–15 µm. Inclusions of the second phase were found along the ...boundaries and in the volume of the grains. The near-boundary volumes of the alloy (volumes located along grain boundaries) are enriched in chromium and iron atoms, the volume of grains is enriched in nickel and aluminum atoms, and cobalt is quasi-uniformly distributed in the alloy. The inclusions of an elongated shape are enriched in chromium, iron, and oxygen atoms and may be carbides. Microhardness, modulus of elasticity, and tribological properties of the alloy are determined and the stretch curves are analyzed. Irradiation of the HEA with a pulsed electron beam is accompanied by the release of grain boundaries from precipitates of the second phase, which indicates the homogenization of the material. High-speed crystallization of the molten surface layer of HEA samples is accompanied by the formation of a columnar structure with a submicrometer-nanocrystalline structure. The electron-beam processing decreases the microhardness of the surface layer of the alloy with a thickness of up to 90 µm, which may be due to the relaxation of internal stress fields formed in the initial material during its manufacture. Irradiation of a high-entropy alloy with an intense pulsed electron beam improves the strength and plasticity of the material, increasing the compressive strength by 1.1–1.6 times.
A coating of high-entropy Cantor alloy FeCoCrNiMn of nonequiatomic composition was formed on a 5083 aluminum alloy substrate by wire-arc additive manufacturing (WAAM). The methods of physical ...materials science were applied to analyze the structure, elemental composition, microhardness, and wear resistance of the coating–substrate system. The deposition of the FeCoCrNiMn high-entropy coating on the 5083 alloy surface is accompanied by the formation of microhardness and elemental composition gradients. Microcracks and micropores were revealed in the cross section of the coating. Microhardness in the volume of the coating is 2.5–3.5 GPa and increases to 9.9 GPa at the boundary with the substrate. In the middle part of the coating, the wear factor is 2.3 × 10
–4
mm
3
/N m; the friction coefficient is 0.7. A transition layer up to 450 µm thick is formed at the interface between the coating and the substrate. We analyzed the elemental composition gradient of the transition layer and noted a high level of chemical homogeneity of the coating. The found doping of the coating with substrate elements (aluminum) leads to the formation of a FeC-oCrNiMnAl high-entropy coating, causing a lamellar structure at the interface between the transition layer and the substrate.
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