Solid Solution Phase Research Articles

Phase diagram of ternary Co–Fe–Ge system (I): Experimental

Co–Fe–Ge is an important material system for magnetic and catalyst applications. However, phase equilibria information of the Co–Fe–Ge ternary system is limited. Ternary Co–Fe–Ge alloys equilibrated at 950 °C were prepared. The microstructures, chemical compositions and crystal structure of each phase were determined. The phase equilibria isothermal section at 950 °C of the Co–Fe–Ge ternary system was then proposed. A continuous solid solution phase was formed between the Co5Ge3 and Fe5Ge3 phases and was labeled the β(Co,Fe)5Ge3 phase. There are five three-phase regions in the system at 950 °C. A wide α2 single-phase, and liquid phase regions with large composition ranges being confirmed at the Ge-poor and Ge-rich sides, respectively.

Microstructure and high-temperature oxidation resistance of in-situ Al2O3 reinforced AlCrFeTiV high-entropy alloy with boron microalloying

In this study, the effect of boron (B) on the microstructure and high-temperature oxidation resistance of AlCrFeTiV high-entropy alloy (HEA) coatings were investigated via laser cladding on Ti-6Al-4 V. The study findings indicate that AlCrFeTiVBx (x=0, 0.5, and 1 at%) HEAs coatings mostly comprise BCC solid solution phase, TiO2 and Al2O3 ceramic particles, which formed by oxygen (O) in the air reacts with Titanium (Ti) and Aluminum (Al) of coatings. Besides, the introduction of minor B should effectively reduce the formation of TiO2. Increasing the B content, significantly promoted the high-temperature oxidation resistance of HEAs coatings at 900 °C for 50 h. When x = 1, the coating exhibits the best high-temperature oxidation resistance. Furthermore, the oxidation mechanism of the coating was studied using first-principles calculations, and further investigation was utilized on the charge transfer of oxygen adsorbed on the BCC (1 0 0) surface.

Activation of deformation twinning in ultrafine-grained high-entropy alloys via tailoring stacking fault energy and critical twinning stress

In this study, we propose a new material design approach to activate deformation twinning in ultrafine-grained (UFG) AlCoCrCuFeNiTi-based high-entropy alloys (HEAs) by considering both thermodynamic and microstructural aspects. Stacking fault energy of the solid-solution phase is reduced by tailoring composition with increasing Co/Ni ratio and diminishing the concentration of Al and Ti through precipitation. Furthermore, grain size is adjusted to enable the flow stress to surpass the critical twinning stress. It results in the activation of nano-twinning in the UFG HEAs, making the alloys exhibit high strain-hardening after yielding from 1.6 to 2.3 GPa.

On the Microstructure and Properties of Complex Concentrated bcc Solid Solution and Tetragonal D8m M5Si3 Silicide Phases in a Refractory Complex Concentrated Alloy

In this work, the refractory complex concentrated alloy (RCCA) 3.5Al–4Cr–6Ge–1Hf–5Mo–36Nb–22Si–1.5Sn–20Ti–1W (at.%) was studied in the as cast and heat treated conditions (100 h or 200 h at 1500 °C). There was strong macrosegregation of Si in the 0.6 kg button/ingot of the cast alloy, in which A2 solid solution, D8m βNb5Si3, C14-NbCr2 Laves phase and Tiss and a ternary eutectic of the A2, D8m and C14 phases were formed. The partitioning of Ti in the as cast and heat treated microstructure and its relationships with other solutes was shown to be important for the properties of the A2 solid solution and the D8m βNb5Si3, which were the stable phases at 1500 °C. The near surface microstructure of the alloy was contaminated with oxygen after heat treatment under flowing Ar. For the aforementioned phases, it was shown, for the first time, that there are relationships between solutes, between solutes and the parameters VEC, Δχ and δ, between the said parameters, and between parameters and phase properties. For the contaminated with oxygen solid solution and silicide, trends in relationships between solutes, between solutes and oxygen content and between the aforementioned parameters and oxygen content also were shown for the first time. The nano-hardness and Young’s modulus of the A2 solid solution and the D8m βNb5Si3 of the as cast and heat-treated alloy were measured using nanoindentation. Changes of nano-hardness and Young’s modulus of the A2 solid solution and D8m βNb5Si3 per solute addition for this multiphase RCCA were discussed. The nano-hardness and Young’s modulus of the solid solution and the βNb5Si3, respectively, were 9.5 ± 0.2 GPa and 177.4 ± 5.5 GPa, and 17.55 ± 0.5 GPa and 250.27 ± 6.3 GPa after 200 h at 1500 °C. The aforementioned relationships and properties of the two phases demonstrated the importance of synergy and entanglement of solutes, parameters and phases in the microstructure and properties of the RCCA. Implications of synergy and entanglement for the design of metallic ultra-high temperature materials were emphasised.

Investigating magnetic, and magneto-electric properties of Nd doped [(1-y) Bi1-xNdxFeO3-yPbTiO3] solid solution

Magneto-electronic devices applications of room-temperature multiferroics have been made possible by recent developments. But the potential use of pure BFO in multifunctional devices is constrained by its antiferromagnetic nature and need substitution-induced modification to improve magnetic and magnetoelectric properties. In the present paper, attempt has been made to improve the magnetic and magnetoelectric properties of the BiFeO3-PbTiO3 solid solution by incorporating Bismuth cation with Lead(II) ion and Ferric cation with Titanium cation into the formulation of Nd doped,(1-y)Bi1-xNdxFeO3-yPbTiO3where x = 0.05,0.10,0.15,0.20 and y = 0.1, 0.2,0.3 and 0.4. The impact of different PbTiO3 and Nd compositions on magnetoelectric and magnetic characteristics of solid solution has been investigated. The results showed that, degree of magnetization continuously increases with increasing Nd doping by affecting Fe-O-Fe angles. However, the magnetization drops as the volume of PbTiO3 rises, that may be attributed to a rise in the tetragonal phase of solid solutions. The improvement of the magnetoelectric coupling coefficient and change of antiferromagnetic behaviour to ferromagnetic behaviour of solid solutions has been observed with increasing Nd doping. This enhance the ferromagnetic behaviour of the compound.

Multi-objective optimization and machine learning assisted design and synthesis of magnesium based novel non-equiatomic medium entropy alloy

Non equiatomic compositionally complex alloys have gained significant attention due to their unique combinations of properties including high strength, good ductility, excellent thermal stability and corrosion resistance. The non equiatomic compositions provide flexibility in tailoring the mechanical, thermal, magnetic, biomedical and other functional properties to meet the specific application requirements. In this study, a novel design approach was proposed to identify quaternary non equiatomic medium entropy alloy for biomedical application. The design methodology employs multi-objective optimization of empirical phase formation parameters and ML algorithm to design solid solution containing non equiatomic medium entropy alloy. The suggested approach scans over a large composition space to find possible non-equiatomic compositionally complex alloy compositions (CCA) with desired phases. The proposed methodology is an alternative to trial-and-error alloy fabrication and CCA design approach reported in the literature. This step significantly reduced the time and resources utilized in CCA design by decreasing the number of experimental runs. Based on the design strategy, Mg60Ti24.24Zn9.66Nb6.1 alloy was designed and selected for fabrication through powder metallurgy route by employing microwave sintering. The Mg rich alloy exhibited the presence of two solid solution phases viz HCP and BCC in both prealloyed powder and final sintered specimen. The developed alloy showed a high microhardness value of 153.9 ± 0.85HV with a measured density of 2.82 ± 0.03 g/cm3. The mechanical properties such as yield strength, ultimate compressive strength, elastic modulus and fracture strain of the developed alloy were found to be superior to that of pure Mg and AZ31 fabricated through the same manufacturing route. Mechanical properties of local phases present within the alloy were assessed through nanoindentation technique. Elastic modulus (E) and hardness (H) values for the Ti rich BCC phase were 118.9±7.2 GPa and 4.65±1.1 GPa, respectively, whereas the Mg rich HCP phase showed values of 65.2±7 GPa and 1.6±0.43 GPa, respectively. Furthermore, with minor changes to the constraint equations and correct ML dataset selection, the suggested design technique can be applied to any multi-principal element alloy system to design non-equiatomic compositions.

Ultrasonic-enhanced silver‑indium transient liquid phase bonding in advancing rapid and low-temperature packaging

Transient liquid phase (TLP) bonding technique is one of the promising solutions to third-generation wide-bandgap semiconductor power packaging. However, its prolonged heating process of the components restricts its application to some extent. To address this issue, the singular impact of acoustic cavitation induced by ultrasound emerges as a promising solution. For the first time, this study proposes the incorporation of ultrasound into the silver‑indium (Ag-In) TLP bonding process, enabling rapid and efficient bonding with 50 μm interlayers within seconds, while achieving a maximum shear strength of 60 MPa. A comprehensive comparative and analytical investigation of the interfacial microstructure, mechanical properties, and grain distribution has been carried out, in comparison to that of the conventional Ag-In TLP joint. The overall temperature profile was monitored utilizing a non-contact infrared camera and subsequently corroborated with finite element simulation outcomes. The phase analysis unveiled a predominant composition of the solid solution phase (Ag)-In within the bonding region, which contributes to a pronounced enhancement of the mechanical properties of the joints. Transmission electron microscopy (TEM) confirmed the complete degradation of the initial bonding interface, resulting in a bond with a bulk-like appearance. Finally, this work has elucidated the underlying mechanisms for the ultrasonic-enhanced transient liquid phase bonding (U-TLP) joint formation, where the influence of acoustic cavitation on element diffusion and the metallurgical bonding process has been discussed.

Effect of TiC nanoparticles on microstructure and corrosion resistance of laser cladding Al-CNTs composite coatings on AZ31 alloy

ABSTRACT Al-CNTs composite coatings were successfully prepared on AZ31 alloy using laser cladding (LC). The effect of TiC nanoparticles on microstructure and corrosion resistance of the LC Al-CNTs and Al-TiC-CNTs composite coatings were investigated. The LC composite coatings were composed of α-Mg solid solution phase and β-Al12Mg17, Mg2Al3, Mg32(Al,Zn)49 and TiC compound phases. A sound metallurgical bonding interface was produced between the LC composite coatings and AZ31 alloy. The surface microhardness and corrosion resistance of the LC composite coatings, which were gradually decreased with increasing the content of carbon nanotubes (CNTs) and TiC nanoparticles, were significantly enhanced compared to those of the AZ31 alloy. The LC Al-CNTs (99 wt% Al + 1 wt% CNTs) composite coating exhibits excellent surface microhardness and corrosion resistance. The mean surface microhardness, self-corrosion potential and self-corrosion current were 266.4 HV, −1.233 V and 2.55 × 10−5 A, which were 426.2%, 78.9% and 16.5% of the AZ31 alloy, respectively.

Study on the microstructure and wear resistance of AlCrCuFeNiTix high entropy alloys for surfacing welding

In order to investigate the effect of Ti element content on the microstructure and wear resistance of AlCrCuFeNiTix (x = 0, 0.3, 0.6, 0.9) high entropy surfacing alloy, a melting electrode gas shielded welding technology was used to prepare AlCrCuFeNiTix high entropy surfacing alloy on the surface of carbon steel plates. The microstructure, phase composition, and wear resistance of the alloy were analyzed. The results show that the phase composition of the surfacing alloy becomes a BCC+FCC solid solution phase, with a much higher content of BCC phase than FCC phase. The microstructure consists of disordered BCC phase rich in Fe and Cr, ordered BCC phase rich in Al and Ni, and FCC phase rich in Cu. The microstructure exhibits typical dendritic (DR) and interdendritic (ID) structures. With the increase of Ti element, hard Fe2Ti phase precipitates in the interdendritic zone, and the micro hardness of the alloy shows an increasing trend. The maximum hardness can reach 636 HV, which is 2.4 times that of the base material. With the increase of Ti element, the friction coefficient of the alloy shows a trend of first decreasing and then increasing, and the wear amount first decreases and then increases. When Ti is 0.6, the wear resistance of the high entropy surfacing alloy reaches its best.

Achieving high mechanical and corrosion resistance synergy properties of the Mg-11Li-6Al alloy through simple solutionizing treatments

This study aims to investigate the impact of solutionizing treatments on the mechanical and corrosion resistance properties of the Mg-10.93Li-5.45Al-0.08Er (LA116) alloy. The as-cast LA116 alloy is primarily composed of a single β phase along with AlLi and MgLiAl2 phases. Results demonstrate that the mechanical and corrosion resistance properties of the alloy experience considerable improvement after solutionizing treatments due to the synergistic effect of phase compositions and solid solution strengthening. Specifically, at 400 °C, the mechanical properties of the alloy witness a significant improvement due to the coordination of solid solution strengthening and the dissolution of the second phase. In contrast, the best corrosion resistance is observed at 250 °C due to the decomposition and uniform distribution of the AlLi phase.

Microstructural evaluation and mechanical properties of WC-6%Co/AISI 1045 steel joints brazed by copper, brass, and Ag-based filler metals: Selection of the filler material

Due to the higher production cost of the monolithic carbide tools as well as their brittle nature, cemented carbides such as WC-Co are frequently joined to tool steel. To overcome the joining complications that arise due to notable differences in thermal expansions between the components and the poor wettability, various investigators have used copper-based and silver-based filler metals to dissimilarly braze the cemented carbides to steels. However, researchers do not agree about the selection of filler material. This research investigates the use of pure copper, brass, and silver-based filler metals to join the WC-Co cemented carbide to AISI 1045 steel. In this regard, microstructural features and mechanical properties including microhardness and shear strength were studied. The results indicate the formation of Cu(Fe,Co) solid solution and η carbides at the joint interfaces as well as the development of various precipitated phases in the joint area comprising Fe-Zn and Co-Zn intermetallic compounds. The reaction layers at both sides of the joints accompanied by cobalt-depleted zone on the hard metal side were observed. While using the α−β brass interlayer, the increase in hardness of the joint area through the presence of (Cu,Zn) solid solution compared to pure copper, the joint shear strength was enhanced from 161 to 173 MPa. On the other hand, the utilization of silver-based filler alloy with a distribution of hard copper-rich solid solution phase (182 HV) embedded in a silver-rich ductile matrix (88 HV), presenting a dispersion hardening effect, improved the shear strength of the joint to 203 MPa.

Ultrasonic non-destructive evaluation study of molecular diffusion bonding of thin copper-aluminum electrode sheets

The weld quality of copper and aluminum thin electrode sheets in molecular diffusion bonding was non-destructively evaluated using ultrasonic resonance techniques. During the welding process, the intermediate layer material nickel diffuses into the molecules of both the copper sheet and aluminum sheet, resulting in the formation of a solid solution phase layer. This leads to a 5-layer structure in the welded body. If there are defects in this solid solution phase layer, it can cause mutations in the ultrasonic resonance signals within the weld body. In order to characterize the weld quality between copper and aluminum sheets, an acoustic attenuation coefficient was introduced. The ultrasonic resonance signals within the weld body of copper and aluminum thin electrode sheets were analyzed under four different welding states. Experimental testing revealed significant differences in acoustic attenuation coefficients among these different welding states. A smaller acoustic attenuation coefficient indicates better welding quality. Therefore, by setting a reasonable threshold for this coefficient, it is possible to effectively evaluate the welding quality of molecular diffusion bonding between copper and aluminum thin electrode sheets.

SYNTHESIS AND INVESTIGATION OF SOME PHYSICOCHEMICAL PROPERTIES OF NANOSTRUCTURED CO-PT SYSTEM

The phase compositions and particle morphology of nanostructured Co-Pt system, obtained by the reduction of aqueous solutions of precursors with hydrazine hydrate, have been studied (for the first time in the Pt-rich region) by X-ray diffraction analysis (XRD), transmission electron microscopy (coupled with electron diffraction (ED)), thermogravimetry, small-angle X-ray scattering analysis (SAXS) and elemental analysis of the samples. As determined by XRD, with Co content less than approximately 60 at%, the only phase is determined: the face-centred cubic (fcc) phase of the solid solution of Co in Pt, with the upper limit of Co solubility in Pt equal to 18±1 at%. For Co content in the solid solution higher than its solubility limit during the synthesis, diffraction-undetectable phase (phases) is also formed in addition to the fcc solid solution phase. The presence of such phases was confirmed by the results of SAXS, and their metal nature, rather than oxide-hydroxide one, was confirmed by XRD, ED, and thermal analysis.

Pressure-induced superconductivity in SnSb2Te4

Owing to their unique compositional and structural characteristics, layered van der Waals solids in binary and ternary chalcogenide families provide a fertile testbed for exploring novel exotic structures and states, e.g., topological insulators and superconductors. Herein, a comprehensive study on the structural variations and correlated electrical transport behavior of SnSb2Te4, a ternary member, has been carried out considering elevated pressures. Under 45.6 GPa, three distinct structural phase transitions have been observed, with strong evidence from the variations of high-pressure X-ray diffraction patterns. The onsets of phase II (monoclinic, C2/m ) at 6.3 GPa, phase III (monoclinic, C2/c ) at 15.5 GPa, and phase IV (body-centered cubic with substitutional disorder, Im-3m ) at 17.2 GPa have been observed owing to the emergence of new diffractions. Based on electrical measurements at low temperature and high pressure conditions, two pressure-induced superconducting states have been distinguished in SnSb2Te4. The first state occurs in the range of 12.3-17.1 GPa. The positive pressure dependence on Tc indicates that the aforementioned state is related to the monoclinic C2/m phase. At > 17.1 GPa, the second superconducting state emerges, with the negative pressure dependence on Tc . It relates to the body-centered cubic solid solution phase, which is characteristic of a substitutional disordered crystal structure. The discovery that the pressure-induced superconductivity in SnSb2Te4 is affected by structural phase transitions under pressure may help understand the universal relationship between the ambient condition topological insulating state and derived superconductivity. Ab initio theoretical calculations reveal that an electronic topological transition takes place at approximately 2.0 GPa, which is featured by the obvious changes in the distribution of electronic density of states near the Fermi level.

Effect of Oxygen in Mo-TM (TM = Ti, Zr, Hf) Solid Solutions as Studied with Density Functional Theory Calculations

Mo-Ti-Si, Mo-Zr-B, and Mo-Hf-B are promising alloy systems for high-temperature applications as they show higher toughness and higher creep resistance than other Mo-based alloys. Regarding ductility and toughness, the chemical composition of the Mo solid-solution phase is the main parameter with which to tweak these properties of multiphase Mo-based alloys. Besides the common solid-solution hardening, one goal is to minimize embrittlement by decreasing the detrimental effects of interstitials like oxygen atoms in Mo alloys, which might be present in the bulk material due to trapping. For a better understanding of the trapping mechanisms and behavior of Mo solid solutions, the bonding situation and interaction of Mo atoms with the atoms of the alloying partners, as well as oxygen atoms, is worthwhile to investigate. For this, an in-depth analysis of the chemical bonding situation with calculations based on density functional theory in selected Mo-TM(-O) (TM = Ti, Zr, Hf) solid solutions is conducted in this work. It is shown that Ti atoms in a Mo solid solution are strong traps for oxygen atoms, while Hf and, even more clearly, Zr atoms are not. It is pointed out that the ionic and covalent interactions are the primary influence on the trapping behavior, as the change in ionic and covalent interactions between trapping and nontrapping models follows the trend Mo-1Ti > Mo-1Hf > Mo-1Zr, which resembles the trend of the trapping energy.

Structure, antibacterial property and cytocompatibility of sputter deposited MoO–Ag films

MoO–Ag films with silver content up to 18.6 at.% along with MoO films were prepared by magnetron sputtering. The film color reveals oxidation of Mo element in both groups of films. XRD analysis shows bcc Mo phase, fcc Mo(O) solid solution and fcc silver phase (only for MoO–Ag films), and XPS analysis reveals oxidation of Mo element. SEM displays the increased density of silver nanoparticles at film surface with silver content of the MoO–Ag films. With the addition of oxygen the conductivity of MoO films is decreased to above 2 kΩ. Both groups of samples are hydrophilic, with the contact angles of 51.2–83.9°. The electrochemical test suggests microgalvanic coupling in the composite MoO–Ag film (11.8 at% Ag). The composite film sample also has the higher Mo ion releasing rate in water. Both groups of films exhibit good antibacterial activity against E. coli (antibacterial ratio up to 100%) contributed by the released Mo and Ag ions. The extracts of MoO–Ag films with silver content up to 11.8 at% are well compatible with MC3T3-E1 cells. With the biologically advantageous Mo element and acceptable released Ag ion concentration, the sputter deposited MoO–Ag films would have high potential in biomedical applications.

Hot-dip aluminizing of Fe–Cr–B cast steel in Al–Ti–B alloy melt

The periodic layered structure (PLS) composed of alternative arrangement of Cr–Al–B MAB phase and FeAl3 was formed at the (Cr, Fe)2B/Al interface during hot-dip aluminizing (HDA) of Fe–Cr–B cast steel in molten Al. However, the effect of alloying element in the Al melt on the PLS was still unknown. This work focused on the effect of Ti on the interfacial reaction between Fe–Cr–B cast steel and molten Al–Ti–B alloy. The Ti atoms in Al–Ti–B alloy melt could partially replace the Cr atoms in the M-sites of the Cr–Al–B MAB phase contained in the PLS after it formed in-situ, leading to the formation of (Cr, Ti)–Al–B MAB phase solid solution. The B atoms in the melt absorbed by the Cr–Al–B MAB phase also accounted for the blackening of the Cr–Al–B MAB phase. It was the first time that the M-site MAB phase solid solution in the Cr–Al–B system was prepared by hot-dip aluminizing.

Effect of intermetallic compounds on the high-temperature oxidation resistance of Al0.25CoCrFeNiCuAux (x = 0, 0.1, 0.3) high-entropy alloys

In this work, the effect of gold alloying on the microstructure, phase composition, and high-temperature oxidation resistance of Al0.25CoCrFeNiCu high-entropy alloy (HEA) was studied. It is shown that gold is partly incorporated in the dendritic face-centered cubic (fcc) phase, and it is mainly precipitated as intermetallic compounds (ICs) in the interdendritic space. Al2Au and AuCu3 ICs could be precipitated depending on the concentration of gold. The formation of Al2Au ICs increased the parabolic oxidation rate constant (kp) from 378.5 × 10–13 (g2/cm4s) for Al0.25CoCrFeNiCu to 1079.5 × 10–13 (g2/cm4s) for Al0.25CoCrFeNiCuAu0.1 HEA, while the precipitation of AuCu3 in Al0.25CoCrFeNiCuAu0.3 HEA reduced this index to kp = 94.9 × 10–13 (g2/cm4s). Microstructural analysis of the oxidized samples revealed that binding of aluminum into Al2Au IC decreases the amount of available aluminum in the solid solution phase to form a protective Al2O3 oxide layer on the surface of Al0.25CoCrFeNiCuAu0.1 alloy during high-temperature oxidation. On the contrary, the binding of copper with gold into AuCu3 IC effectively prevents Cu from oxidation and provides routes for the formation of a dense layer of Al2O3 oxide with superior protective properties.

Cobalt–Magnesium Oxide Catalysts for Deep Oxidation of Hydrocarbons

Co–Mg catalysts for methane combustion were synthesized and studied, revealing the transformation of MgCo2O4 spinel into a CoO–MgO solid solution with oxygen release from the spinel lattice as the calcination temperature increased. Repeated heat treatment of the calcined solid solution at lower temperatures led to spinel regeneration with segregation of the solid solution phase. A TPR of the samples showed the presence of two characteristic peaks, the first of which relates to the transition of Co3+Oh spinel to the Co2+Oh structure of CoO, and the second to the reduction of CoO to Co°. The second peak was observed at 540–620 °C for samples calcined at temperatures below spinel decomposition, and for high-temperature samples at 900–1100 °C. Taking into account the identity of the structure of phases obtained in both cases, the formation of not a true CoO–MgO solid solution, but rather a mixture of ordered oxides (“pseudo-solid solution”) in the low-temperature region, was postulated. A study of the activity of the samples showed the high activity of the spinel systems and a linear relationship between the activation energy of methane oxidation and the heat treatment temperature.

Microstructures and Properties of FeCoNiCr High-Entropy Alloy Coatings Prepared by Electrodeposition

High-entropy alloys (HEAs) have attracted increasing attention owing to their multicomponent characteristics with notable high-entropy effects. However, obtaining HEAs with improved properties is still challenging. The properties of HEAs can be modulated by the fabrication technique. Electrodeposition could achieve the desired performance characteristics of HEA coatings while operating at reduced processing temperatures and energy consumption levels. Herein, novel FeCoNiCr HEA coatings were electrodeposited on copper substrates under various current densities. The microstructure, coating thickness, hardness, wear resistance, and corrosion properties of the FeCoNiCr HEA coatings prepared at different current densities were all examined. X-ray diffraction revealed HEA coatings with a single disordered face-centered cubic solid solution phase. Scanning electron microscopy indicated uniform and dense surfaces of FeCoNiCr HEA coatings fabricated under a current density of 25 A/dm2, with significantly reduced coating cracking and improved structural integrity. The coatings prepared at 25 A/dm2 also exhibited maximum thickness and favorable bonding with the substrate, as well as notably enhanced wear resistance. As the preparation current density increases, the hardness of the coating increases. The hardness of the coating reaches its maximum at 30 A/dm2. FeCoNiCr HEA coatings fabricated under a current density of 25 A/dm2 in a 3.5 wt% NaCl solution simulated seawater conditions demonstrated improved electrochemical resistance to corrosion. By comparing the microstructure, elemental content, and properties of coatings prepared at various current densities, it was found that the FeCoNiCr HEA coating prepared at 25 A/dm2 showed the best performance.