B2 Phase Research Articles

Structural electronic and thermodynamic properties of CdX(X: S, Se, and Te) cadmium chalcogenides compound

The structural and electronic properties of (CdS, CdSe, and CdTe) compounds in rock-salt, zinc-blend, and wurtzite crystal structures were calculated using ab initio calculation. In addition to these properties, the thermodynamic properties were added advantage to clarify their comportment as temperature variation. Under the context of density functional theory DFT, the calculations were carried out using the full potential linearized augmented plane wave FP-LAPW approach. The generalized gradient approximations GGA-PBE established by Perdew-Burke-Ernzerhof and the local density approximation LDA and modified Bucke Jhonson have both been employed for the exchange-correlation energy and related potential MBJ. The results show that the zinc-blend phases were the stable crystal structure for all compounds. The lowest direct band gap is found in the B3 phase for CdX, close to the experimental value. The values of band energies of CdS, CdSe, and CdTe were estimated to be 2,463 eV, 1,76 eV, and 1,532 eV, respectively. In general, this work fits well with other experimental and theoretical results. The quasiharmonic Debye theory is used to determine the impact of temperature and pressure on thermodynamic properties. This includes the calculation of pressure and temperature dependence, as well as the analysis of how heat capacity, thermal expansion, and the Debye temperature are affected by these variables.

Electrochemical dissolution behavior of cast and forged Ti2AlNb alloys in NaCl and NaNO3 electrolytes

Although Ti2AlNb alloy has numerous exceptional properties that make it one of the most promising materials in the aerospace field, it also presents significant challenges to traditional machining. Nevertheless, electrochemical machining (ECM) presents distinctive advantages when it comes to processing difficult-to-cut materials. Regrettably, the electrochemical dissolution behavior of Ti2AlNb alloy has not been reported yet. In this study, the electrochemical dissolution behavior of forged and cast Ti2AlNb alloys in 10% NaCl and 20% NaNO3 electrolytes was systematically studied for the first time. In the same electrolyte composition, the passivation film formed on the forged Ti2AlNb alloy surface is thicker than that on the cast Ti2AlNb alloy surface, indicating higher corrosion resistance. Dissolution experiments were conducted on cube and rotary samples, followed by the assessment of surface quality using laser confocal microscopy. The experimental findings demonstrate that ECM in 10% NaCl electrolyte yields better surface quality for both Ti2AlNb alloys. The Ti2AlNb alloy in this study consists of the B2 phase and O phase, with preferential dissolution of the O phase observed during ECM.

First-Principle Study on Tailoring the Martensitic Transformation of B2 Nb50−xTixRu50 Shape-Memory Alloy for Structural Applications

NbRu has a potential as a high-temperature shape-memory alloy (HTSMA) because it has a martensitic transformation temperature above 1000 °C. However, its shape-memory properties could be improved for consideration in the aerospace and automotive industry. The unsatisfactory shape-memory properties could be associated with the presence of a brittle tetragonal L10 martensitic phase. Therefore, in an attempt to modify the transformation path from B2→L10 in preference of either B2→orthorhombic or B2→monoclinic (MCL), an addition of B2 phase stabiliser, titanium (Ti), has been considered in this study to partially substitute niobium (Nb) atoms. The ab initio calculations have been conducted to investigate the effect of Ti addition on the thermodynamic, elastic, and electronic properties of the Nb50−xTixRu50 in B2 and L10 phases. The results showed that the B2 and L10 phases had comparable stability with increasing Ti content. The simulated data presented here was sufficient for the selection of suitable compositions that would allow the L10 phase to be engineered out. The said composition was identified within 15–30 at.% Ti. These compositions have a potential to be considered when designing alloys for structural application at high temperatures above 200 °C.

Microstructure, Mechanical, and Tribological Properties of Nb-Doped TiAl Alloys Fabricated via Laser Metal Deposition.

TiAl alloys possess excellent properties, such as low density, high specific strength, high elastic modulus, and high-temperature creep resistance, which allows their use to replace Ni-based superalloys in some high-temperature applications. In this work, the traditional TiAl alloy Ti-48Al-2Nb-2Cr (Ti4822) was alloyed with additional Nb and fabricated using laser metal deposition (LMD), and the impacts of this additional Nb on the microstructure and mechanical and tribological properties of the as-fabricated alloys were investigated. The resulting alloys mainly consisted of the γ phase, trace β0 and α2 phases. Nb was well distributed throughout the alloys, while Cr segregation resulted in the residual β0 phase. Increasing the amount of Nb content increased the amount of the γ phase and reduced the amount of the β0 phase. The alloy Ti4822-2Nb exhibited a room-temperature (RT) fracture strength under a tensile of 568 ± 7.8 MPa, which was nearly 100 MPa higher than that of the Ti4822-1Nb alloy. A further increase in Nb to an additional 4 at.% Nb had little effect on the fracture strength. Both the friction coefficient and the wear rate increased with the increasing Nb content. The wear mechanisms for all samples were abrasive wear with local plastic deformation and oxidative wear, resulting in the formation of metal oxide particles.

Ultra-high hard and fracture-resistant multi-phase nanocrystalline AlCrFeMoNbNi multi-principal element alloy

Multi-phase nanocrystalline AlCrFeMoNbNi multi-principal element alloy was developed using mechanical alloying followed by spark plasma sintering. Mechanical alloying resulted in a two-phase microstructure (BCC and FCC), whereas subsequent sintering resulted in a multi-phase microstructure consisting of FCC, Rhombohedral and B2 phases. Extremely high hardness values in the range of 35.79–16.05 GPa were measured as a function of indentation load between 25 and 5000 g. A highly pronounced indentation size effect was observed. From classic Nix-Gao analysis, a load independent hardness of 13.82 GPa was estimated. The high hardness arises from a combination of finer grain size and solid solution strengthening (FCC phase) and multi-phase structure consisting of B2 and Rhombohedral phases. The major phase being FCC (83%) offers nearly 85% of the total flow stress realized for this MPEA and the remaining 15% of the flow stress must be arising from both the B2 and Rhombohedral phases. It is to be noted that the phase fractions of B2 and Rhombohedral phases are 10% and 7% respectively. Indentation fracture toughness, evaluated using the cracks developed during Vickers indentation, yielded encouraging numbers in the range 12.28–13.85 MPam. The excellent combination of ultra-high hardness and indentation fracture toughness of this AlCrFeMoNbNi MPEA surpasses the reported data on several related harder materials, including silicides, nitrides, carbides, etc.

Stability of the B2 phase among refractory metals

Energy efficiency demands finding new materials for applications at elevated temperatures. Refractory multicomponent alloys with a BCC/B2 microstructure promise to serve as alternatives to the current state-of-the-art, Ni-based superalloys for applications at higher temperatures. With the vast compositional space of these alloys, the first fundamental question is whether the B2 phase can form among refractory metals. In this study, we span through the periodic table to investigate the potential for creating ordered B2 intermetallics among the refractory metals, using first principles calculations, and establish the correlation between the nature of the atomic bonds and stability of the B2 structure. We use our newly developed Multi-Cell Monte Carlo method to explore the extensive compositional space of these alloys, refine the trends in ordering, and pinpoint the most promising combinations for detailed analysis. We discover that B2 phases form exclusively with the inclusion of elements from groups VII and VIII, such as Re, Ru, and Os, and we identify these phases among a total of eleven elements. Further analysis of the electronic structure and bonding characteristics of these B2 systems reveals a pseudogap in the electronic density of states at the Fermi level. This pseudogap is attributed to the hybridization of d orbitals, leading to the formation of strong covalent bonds in the most stable compounds. This finding explains why B2 formation is restricted to elements from groups IV-VIII and V-VII refractory metals.

Induction mechanisms of high-density nano twins during solidification process: Reducing stacking fault energy of γ phase by Re and forming highly mismatched B2(Re)/α2 interface

It is extremely difficult to introduce high-density nano twins during the solidification process of TiAl alloy. In this study, high-density nanotwins are inducted in the as-cast Ti48Al2Cr alloyed by adding Re element. Phase transformation, morphology characteristics of nano twins, compressive and tensile properties, and the related mechanisms have been studied. Results show that B2 phase enriched with Re tends to precipitate along the α2/γ interface within lamellar colony. The stacking fault energy (SFE) of γ phase decreases from 43 mJ/m2 to 16 mJ/m2 as Re content increases from 0 at.% to 0.6 at.%, decreasing the critical shear stress for twin formation. Compared to the mismatch value of α2/γ interface (0.004), which of B2/α2 and B2/γ interfaces increase to 0.247 and 0.149, respectively. Driven by high interfacial stress, high-density dislocations are generated at the B2/α2 interface, providing the dislocation slip channel for the formation of stacking faults (SFs) and nanotwins at the B2/γ interface. Therefore, the mechanism of inducting high-density nanotwins is to reduce the stacking fault energy of γ phase by Re and form highly mismatched B2/α2 interface. Compressive strength and the strain increase from 1723 MPa to 2398 MPa and 29 % to 39 % as Re content increases from 0 at.% to 0.6 at.%, respectively. Tensile strength increases from 356 MPa to 452 MPa without sacrificing plasticity. The improvement in strength and plasticity are attributed to the nano-twinning strengthening and interfacial thermal mismatch strengthening. Forming nanotwins during solidification process serve as the nucleation sites for newly formed twins during deformation process, increasing the deformation tolerance of TiAl alloy.

Carbon effect on tensile and wear behaviors for a dual-phase Fe61.5Cr17.5Ni13Al8 alloy

High entropy alloys (HEAs) series were produced by doping carbon into Fe61.5 Cr17.5Ni13-xAl8Cx (x = 0, 0.25, 0.5, and 1.5 at.%) by a vacuum arc melting. The carbon doping effect on the phase composition, mechanical properties, and wear behavior was studied. Fe61.5 Cr17.5Ni13Al8 alloy microstructure was a heterogeneous structure comprising FCC, BCC, and B2 phases. By introducing carbon into Fe61.5 Cr17.5Ni13-xAl8Cx (x = 0, 0.25, 0.5, and 1.5 at.%), the BCC phase fraction increased with decreasing FCC phase during annealing, accompanied by the formation of M23C6-like carbides at temperatures of 800 °C and 900 °C. The carbon-doped HEAs exhibited enhanced mechanical properties compared to the carbon-free HEAs, including higher tensile strength (1580 MPa), notable ductility (∼20 %), reduced friction coefficient (0.50), and improved wear resistance. Among the carbon-doped HEAs, the HEA with x = 0.5 at.% and annealed at 800 °C demonstrated exceptional wear resistance due to the compensations of attaining a balance between strength and elasticity.

Twins and β0 precipitation effects on the lamellar degradation in TNM alloy during creep

In this paper, the microstructure instability of the TNM alloy during creep at 800 °C under 150 MPa and 250 MPa was investigated. The results indicate that, both β0 precipitation (inside lamellae) and primary γ twins formation are initiated during the second stage of creep. Compared to low creep stress conditions (150 MPa), high creep stress conditions (250 MPa) accelerate the initiation of the third stage of creep, inducing the precipitation of ω0 phase and secondary twins. The nanoscale ω0 particles formed inside β0 or at the interface of the β0/β0. The intersection of secondary γ twins and α2 lamellae leads to stress concentration and dislocation accumulation, providing nucleation points for β0 phase and promoting the precipitation of β0 within α2 lamellae. The precipitation of the secondary γ twin introduces a unit dislocation of 1/3 [111]γ in the (111) atomic planes, promoting the movement of adjacent atomic planes within the (111) atomic planes. The 1/3 [111]γ dislocations will dissociate into two partial dislocations via 1/3 [111]γ→1/4 [11 1‾]γT +1/9 [0 1‾1]γM. The adjacent atomic planes of the γ matrix and secondary γ twin can transformation to β0 through shear along 1/9 [0 1‾1]γM and 1/4 [11 1‾]γT, respectively. The size and content of β0 phase significantly increase in the third stage of high creep stress, accelerating the decomposition and fragmentation of the α2 lamellae, leading to rapid creep failure.

Laser metal deposition of thin-walled parts of Al0.8CrFe2Ni2 high-entropy alloy: Process window, microstructure, wear resistance and mechanical anisotropy

In this paper, an exponential regression model is employed to analyze the sensitivity of the geometrical characteristics of single track, building efficiency and powder efficiency to the process parameters for the Al0.8CrFe2Ni2 high entropy alloy (HEA) fabricated by laser metal deposition (LMD). Based on the exponential regression model and sensitivity analysis, an effective process window is obtained to deposit a multilayer thin-walled structure. The Al0.8CrFe2Ni2 HEA consists of the (Fe, Cr, Ni)-rich faced centered cubic (FCC) phase and (Al, Ni)-rich B2 phase. An anisotropic mechanical property along the building direction and scanning direction is discovered due to the different strengthening mechanisms and fracture modes. Dislocation strengthening dominates in the building direction, while the high yield strength in the scanning direction is the result of dislocation, grain boundaries and precipitation strengthening. Compared to 400 °C, the Al0.8CrFe2Ni2 HEA has a lower wear rate at 25 °C owing to the self-lubricating protection provided by the completed oxide glaze layer. The findings provide guidelines for improving the anisotropic mechanical properties of thin-walled parts of LMD-deposited HEAs.

Pulsed electric current annealing of (Ni,Cu)-rich Ti49Ni41Cu10 shape memory wire for superior superelasticity and stable elastocaloric cooling effect

This study designed a (Ni,Cu)-rich Ti49Ni41Cu10 shape memory wire annealed by pulsed electric treatment of 60 A/mm2 for 0.3 sec. Granular and strip-type Ti(Ni,Cu)2 precipitates, formed before application of the electric current treatment, facilitated the plastic deformation during the wire drawing process. The wire demonstrated stability in superelasticity and elastocaloric cooling capability. The accumulated residual strain was only 0.15 % after 50 superelastic cycles with an applied strain of 3.5 % at 338 K. The elastocaloric temperature drop of the wire remained at about 9.4 K for 50 cycles. Moreover, under 3 % applied strain, the wire exhibited elastocaloric temperature drops of 5.3 K to 8.1 K within the application window of 323 K to 373 K. TEM observations confirmed that the grain size of the wire was about 20–30 nm, which led to the homogeneous superelasticity performance. Furthermore, the superior compatibility between the B2 and B19 phases reduced plastic deformation at the interfaces during martensitic transformation. The stable functionality and elastocaloric cooling capacity of the wire originated from the combination of nanocrystalline structure and superior compatibility between the B2 and B19 phases. These results demonstrated that the Ti49Ni41Cu10 SMA wire could be fabricated due to the presence of ductile Ti(Ni,Cu)2 precipitates, and the subsequent pulsed electric current treatment caused rapid annealing to achieve a stable functional performance.

Effects of TiB2 contents on the microstructure and oxidation behavior of Mo-Si-B composite coatings

A novel Mo-Si-B-TiB2 composite coating was prepared on Nb-Si based ultrahigh temperature alloy by slurry sintering. The effects of TiB2 contents (1, 3, 5 and 10 wt%) on the microstructure and oxidation behavior of Mo-Si-B composite coatings were revealed. The results show that TiB2 modified Mo-Si-B composite coatings display a bilayer structure, in which the outer layer is composed of MoSi2, Mo5Si3 and TiB2 phases, and the inner layer is composed of (Ti,Nb)5Si4, (Nb,X)5Si3 and (Nb,Ti)B2 phases. The added TiB2 particles are evenly distributed in the outer layer of the coatings. By introducing TiB2 into the coating, the service life of Mo-Si-B composite coatings is extended from 50 h to 100 h at 1250 ℃, the oxidation rate of the coating is reduced from 1.62 to 0.02 mg2 cm−4 h−1. This indicates that the addition of appropriate TiB2 effectively slows down the oxidation rate and significantly improves the oxidation resistance of Mo-Si-B composite coatings. The Mo-Si-B composite coating with 3 wt% TiB2 had the lowest mass gain (3.9 mg/cm2) after oxidation at 1250 ℃ for 100 h, and it exhibited the best oxidation resistance. This is attributed to the formation of composite oxide scale with crack-free, good healing ability, suitable levels of differential thermal expansion and low oxygen permeability.

Kinetic Exploration of Nanoscale Polymorphs through Interface Energy Adjustment.

Traditionally, the study of crystal polymorphism has relied on thermodynamics and measurements averaged over time and the crystal's constituents. This work introduces a kinetic approach to phase identification─millisecond cinematographic electron microscopic imaging of the dynamics of phase transitions of crystals of a few nm in diameter. We demonstrate a remarkable impact of the interface energy on the relative stability of the nanocrystal's polymorphs, enabling in situ manipulation of phase transitions through size increase or decrease. Starting with the B1 NaI polymorph at 298 K, we identified the previously unknown B2 polymorph of a 1 s lifetime upon sublimation of the crystal. From the CsCl liquid phase, we produced the B1 phase, previously described only at 749 K.

Effect of Al content on microstructure and mechanical properties of the (FeCoNiV)100-xAlx high-entropy alloys

It is well known that face-centered cubic (FCC) high-entropy alloys (HEAs) typically have excellent ductility at room temperature but relatively low strength, which greatly limits their structural applications. To address the strength-ductility trade-off, researchers synthesized a series of (FeCoNiV)100-xAlx (x = 0–20 at. %) HEAs, investigated the effect of alloying Al on microstructure and tensile properties, then analyzed the strengthening mechanism. It was found that the crystalline structure changed from an initial single FCC structure to a duplex FCC plus body-centered cubic (BCC) structure and then to a single BCC structure with increasing Al concentration. After homogenization process, the FCC and BCC phases can be transformed to ordered L12 and B2 phases, respectively. These HEAs with duplex FCC/L12 plus BCC/B2 structure exhibit the potential for excellent mechanical properties, and their properties can be modulated by Al content and heat treatment. The properties can be tuned by both Al content and heat treatment, as the Al content can modulate the BCC phase content and the heat treatment can change the ordered structure. A careful analysis reveals that the solid solubility of Al element in this system was only 3.6 at. %, which has a limited effect on the strength. FCC/L12 bears the main plastic strain and the high tensile strength of the alloy is achieved thanks to the contribution of the BCC/B2 phase to the work-hardening rate of the alloy during the early stages of deformation and the unique work-hardening ability of the L12 phase.

Tailored precipitation assisted by laser-induced cellular dislocation network structures in Al0.3CoCrFeNi high entropy alloy

Cellular dislocation network structures play a critical role in strengthening metals, while their ability to tailor the precipitation of second-phase particles has long been overlooked. Herein, a novel strategy combining laser surface treatment and two-steps annealing is proposed to produce B2 network structures in the as-cast Al0.3CoCrFeNi high-entropy alloy. Cellular dislocation network structures are first introduced in the plates by the laser surface treatment on both sides, then the L12 phase is precipitated on the wall of the dislocation networks by annealing at 700 °C. During second annealing at 800 °C, previously precipitated L12 precursors provide kinetically preferred sites and element segregation for the precipitation of the B2 phase, finally forming dense B2 network structures within the defect-scarce matrix. Dislocations can easily move inside the network structures, and they are blocked by the B2 particles in the wall areas, thus presenting a superior strength-ductility synergy.

Non-equilibrium solidification behavior and mechanical properties of undercooled Fe7(CoNi)77B16 muti-principal element alloy

Multi-principal element alloys (MPEAs) have attracted growing attention owing to the vast compositional field and the comprehensive properties. In this work, Fe7(CoNi)77B16 MPEA was undercooled by vacuum melting furnace with low (61 K, 95 K), medium (115 K, 148 K), and high undercoolings (200 K). The maximum growth velocity of the alloy was 0.21 m/s due to the sluggish kinetics effect. The regular eutectic transformed to anomalous eutectic and the primary dendrite refined from 9.1 μm to 3.5 μm with the increase of undercooling. Meanwhile, the phase selection behavior at high undercooling was observed between the stable (Fe, Co, Ni) phase and the metastable (Fe, Co, Ni)23B6 phase. The hardness of primary phase and compressive strength of the undercooled MPEAs were increased to 952.19 HV and 2061.72 MPa, which is much higher than the as-cast alloy. The enhancement of the mechanical properties was attributed to microstructure evolution. The decrease in plasticity resulted from the increasing volume fraction of brittle intermetallic phases. This study helps to theoretically understand the solidification mechanism of the Fe-Co-Ni-B MPEAs and provides a promising way to enhance the mechanical properties of the novel MPEAs.

Large Nonhysteretic Volume Magnetostriction in a Strong and Ductile High-Entropy Alloy.

Rapid development of smart technologies poses a big challenge for magnetostrictive materials, which should not only permit isotropic and hysteresis-free actuation (i.e., nonhysteretic volume change) in magnetic fields, but also have high strength and high ductility. Unfortunately, the magnetostriction from self-assembly of ferromagnetic domains is volume-conserving; the volume magnetostriction from field-induced first-order phase transition has large intrinsic hysteresis; and most prototype magnetostrictive materials are intrinsically brittle. Here, a magnetic high-entropy alloy (HEA) Fe35Co35Al10Cr10Ni10 is reported that can rectify these challenges, exhibiting an unprecedented combination of large nonhysteretic volume magnetostriction, high tensile strength and large elongation strain, over a wide working temperature range from room temperature down to 100 K. Its exceptional properties stem from a dual-phase microstructure, where the face-centered cubic (FCC) matrix phase with nanoscale compositional and structural fluctuations can enable a magnetic-field-induced transition from low-spin small-volume state to high-spin large-volume state, and the ordered body-centered cubic (BCC) B2 phase contributes to mechanical strengthening. The present findings may provide insights into designing unconventional and technologically important magnetostrictive materials.

Temperature induced A1 to B2 structural and magnetic transition in FeRh thin film

The Fe-Rh system offers a diverse range of magnetic phases, making it promising for energy-efficient magnetic devices. A periodic, chemically homogeneous, isotope-periodic nFeRh/57FeRh multilayer system was deposited on a MgO(100) substrate via molecular beam epitaxy, and annealed at various temperatures and durations. To gain deeper insights into the A1 to B2 structural and magnetic transitions, non-destructive techniques such as x-ray diffraction, conversion electron Mössbauer spectroscopy, and neutron reflectometry were employed. The qualitative and quantitative analysis revealed insights into the underlying mechanisms of the transformation from the A1 phase to the B2 phase were described, including the variation of the lattice parameters, grain sizes and hyperfine parameters. Neutron reflectometry revealed no significant long-range diffusion during the phase transition, suggesting a local interchange of neighbouring atoms.

Solidification microstructure and properties of Ni(60-y)Fe20Co10Cr10Aly high-entropy alloys

A series of eutectic high-entropy alloys Ni(60-y)Fe20Co10Cr10Aly (y = 0, 5, 10, 15, 20, 25) were synthesized via non-consumable vacuum melting, followed by investigation into their solidification microstructures and compression properties. The research results reveal that the solidification microstructures transition from a well-distributed FCC phase (y-0, y-5) to a coarse FCC+B2 isometric crystal structure (y-10), subsequently to a primary FCC phase with a (FCC+B2) eutectic structure (y-15), succeeded by a predominant B2 phase with a (FCC+B2) eutectic microstructure (y-20), and ultimately to a BCC+B2 biphasic structure characterized by periodic braided sheets (y-25). The FCC phase demonstrates a substantial concentration of Ni and Fe, the BCC phase shows substantial enrichment primarily in Fe and Cr, while the B2 phase exhibits significant enrichment in Ni and Al. As the Al content increases, the alloys exhibit higher strength but reduced plasticity. Specifically, alloys with y values of 20 and 25 exhibit yield strengths of 1012 MPa and 1477 MPa, respectively, coupled with remarkable plasticity of 41 and 23%, thereby demonstrating robust mechanical properties.

Microstructure, corrosion resistance and high temperature oxidation properties of AlCrFeNiCu high-entropy alloy coating by high-speed laser cladding

AlCrFeNiCu high-entropy alloy (HEA) coating was prepared on Zirconium (Zr) rod by high-speed laser cladding (HSLC) technique. The effect of different laser power and scanning speed on the forming quality of the coating was studied. When the specific energy density was in the range of 3.0–3.2 J/mm2, the AlCrFeNiCu HEA coating with good adhesion to the substrate, low dilution rate (small heat affected zone) and no cracks were obtained. The phase structure, microstructure, microhardness, corrosion resistance and high temperature oxidation resistance of the coating were tested and analyzed. The results show that the AlCrFeNiCu HEA coating is composed of 76.9 % BCC phase and 23.1 % FCC phase, in which the BCC phase is mainly composed of disordered BCC phase rich in Cr and Fe elements and ordered B2 phase rich in Al and Ni elements, and the FCC phase is rich in Cu elements. Due to the rapid cooling of HSLC, the coating structure gradually changes from columnar crystal to equiaxial crystal from bottom to top. The hardness of the coating is as high as 805 HV, which may be caused by the solution strengthening effect, lattice distortion effect and slow diffusion effect of HEA. In 3.5 % NaCl solution and 0.1 mol/L KOH solution, the self-corrosion current density of the coating is 4.209 × 10−8 A/cm2 and 4.331 × 10−8 A/cm2, respectively. The passivation film on the surface of the coating is composed of a variety of oxides, and the oxygen vacancy density of the passivation film in the two solutions is 2.552 × 1020 cm−3 and 5.794 × 1020 cm−3, with fewer pitting pits on the surface. The structural integrity of the coating can be maintained after 60 min oxidation at 1200 °C. The oxidation process follows the growth kinetics curve, and the surface oxides mainly comprise FeAl2O4, Al2O3 and Cr2O3. AlCrFeNiCu HEA coating improves the corrosion resistance and high temperature oxidation resistance of the Zr-4 alloy.