High Entropy Alloy Thin Films Research Articles

Effect of C additives with 0.5 % in weight on structural, optical and superconducting properties of Ta–Nb–Hf–Zr–Ti high entropy alloy films

We investigated the superconducting (SC) properties of Ta–Nb–Hf–Zr–Ti high-entropy alloy (HEA) thin films with 0.5 % weight C additives. The C additives stabilize the structural properties and enhance the SC critical properties, including μ0Hc2 (13.45 T) and Tc (7.5 K). The reflectance of the C-added HEA film is enhanced in the low-energy region, resulting in a higher optical conductivity, which is consistent with the lower electrical resistivity. In addition, we observed SC vortices in the C-added HEA film using magnetic force microscopy. The magnetic penetration depths (λ) of the pure HEA and C-added HEA films were estimated from their Meissner force curves by comparing them with those of a reference Nb film. At 4.2 K, the λ of the C-added film is 360 nm, shorter than that of the pure HEA film (560 nm), indicating stronger superconductivity against an applied magnetic field.

Single-Phase L10-Ordered High Entropy Thin Films with High Magnetic Anisotropy.

The vast high entropy alloy (HEA) composition space is promising for discovery of new material phases with unique properties. This study explores the potential to achieve rare-earth-free high magnetic anisotropy materials in single-phase HEA thin films. Thin films of FeCoNiMnCu sputtered on thermally oxidized Si/SiO2 substrates at room temperature are magnetically soft, with a coercivity on the order of 10Oe. After post-deposition rapid thermal annealing (RTA), the films exhibit a single face-centered-cubic phase, with an almost 40-fold increase in coercivity. Inclusion of 50 at.% Pt in the film leads to ordering of a single L10 high entropy intermetallic phase after RTA, along with high magnetic anisotropy and 3 orders of magnitude coercivity increase. These results demonstrate a promising HEA approach to achieve high magnetic anisotropy materials using RTA.

Performance and mechanism of electrocatalytic oxidation of urea based on carbon-doped FeCoNiCrMn high entropy alloy film

The application and research of high entropy alloy electrodes in urea oxidation reactions (UOR) are significant. In this study, FeCoNiCrMn, FeCoNiCrMnO, and FeCoNiCrMnC high entropy alloy thin films were prepared by magnetron sputtering by controlling the sputtering power, varying the sputtering atmosphere, and using double target co-sputtering, respectively. The microstructure and surface morphology of the electrode were observed and analyzed by X-ray diffraction, scanning electron microscope, transmission electron microscope, and atomic force microscope. In addition, the chemical state of the elements on the electrode surface was analyzed by X-ray photoelectron spectroscopy (XPS) to clarify the mechanism related to the excellent UOR performance of the electrode. The study found that a small amount of carbon doping can greatly improve the UOR performance of this type of electrode. The amorphous FeCoNiCrMnC electrode has more potential UOR active sites than the face-centered cubic FeCoNiCrMn electrode. After cyclic voltammetry (CV), the potential active sites of the electrode are activated, and the active substances of these electrodes are increased, furthermore, the UOR performance of these electrodes has improved. Since it has 200 cycles of CV, the 10 mA cm−2 potential of FeCoNiCrMnC electrode for UOR is only 1.337 V. After 100 days of natural aging, the catalytic ability of the electrode not only did not decrease but slightly improved, with a potential of 1.321 V at 10 mA cm−2, reflecting the good stability of the catalytic electrode.

Effect of bias voltage on the structure and properties of CoCrFeNi high entropy alloy thin films prepared by magnetron sputtering

In this study, CoCrFeNi high entropy alloy thin films were prepared on 304 stainless steel and single crystal Si substrates using the direct-current magnetron sputtering process under different bias voltages. The effects of these bias voltages on the film micrographs, phase structure, surface roughness, corrosion resistance, and mechanical characteristics of thin films were studied by a scanning electron microscope, transmission electron microscope, X-ray diffractometer, atomic force microscope, electrochemical workstation and nanoindentation tester, respectively. The results indicated that all films exhibited equiaxed nano-scale grains and developed a columnar structure. Fe, Co, Cr, and Ni were uniformly dispersed in all films and all films displayed face centered cubic solid solution (FCC). At a bias voltage of 0 V, the CoCrFeNi HEAs film formed a FCC single phase. With increasing bias voltage, the crystallinity decreased and then increased, reaching the worst crystalline state at bias voltage of −200 V due to the fact that the structure of the film was composed of FCC nanocrystalline and amorphous biphasic structure. Meanwhile, the surfaces of the film prepared at bias voltage of −200 V exhibited the densest structures and the least roughness, with grain sizes reaching a minimum value of approximately 10 nm. In addition, columnar grains of the film prepared at a bias voltage of −200 V displayed the densest state and had the least size, thus this film displayed the best corrosion resistance of a minimum value 1.51 × 10−7 A/cm2, a maximum hardness of approximately 11.18 ± 0.2 GPa and a maximum elastic modulus of approximately 193 ± 2.8 GPa. The passivation films of CoCrFeNi HEAs films were mainly composed of Cr2O3.

A dual-phase Fe-Co-Ni-Cr-Mn high entropy alloy thin film with superior strength and corrosion-resistance

Improving the mechanical properties of high-entropy alloys (HEAs) with a face-centered cubic (fcc) structure is critical for their potential applications. In this work, a Fe-Co-Ni-Cr-Mn thin film was prepared and deposited with a power of 360 W. This alloy thin film exhibits a dual-phase microstructure consisting of a fcc matrix and sigma phase (σ phase) precipitates. The 360 W-film shows ultra-high strength-ductility synergy, with a hardness of 10.4 GPa, yield strength of 6.2 GPa, and a fracture strain of ∼25 % (micro-pillar compression tests). The excellent mechanical properties can be mainly attributed to the grain size effect, the hardening effect of the σ precipitates, and deformation twinning. Moreover, this alloy thin film exhibits excellent tribological performances and corrosion resistance. Our results demonstrate high potential of the dual-phase HEA thin film for industrial applications as high-performance protective coating materials.

Effect of sputtering power and substrate bias on microstructure, mechanical properties and corrosion behavior of CoCrFeMnNi high entropy alloy thin films deposited by magnetron sputtering method

The CoCrFeMnNi high entropy alloy thin films with crystalline (solid solution) structure or amorphous state were fabricated by magnetron sputtering process at different target powers and different substrate bias. Effects of the target power and substrate bias on the characteristics of the CoCrFeMnNi thin films such as microstructures, morphology and surface topography, as well as mechanical properties and corrosion behavior were studied. Phase prediction was calculated by using thermodynamic and kinetic criteria under various deposition conditions. The enthalpy, entropy, δ and Ω parameters, and electronegativity differences influenced the solid solution stability of thin films. These parameters led to the formation of solid solutions with crystalline or amorphous structures under specific limits, which corresponded to the practical XRD and TEM analysis results. Using a substrate bias in the deposition of CoCrFeMnNi thin film changed the amorphous structure to a crystalline (solid solution (BCC + FCC)) at higher target powers (200 and 300 W). On the other hand, the film structure was entirely amorphous at all sputtering target powers without the substrate bias. The mechanical properties, such as hardness, Young's modulus, film strength, and fracture toughness of CoCrFeMnNi thin film, can be enhanced by using the substrate bias and increasing the sputtering power. The potentiodynamic polarization test in 3.5 wt% NaCl aqueous solution indicated that the deposition of CoCrFeMnNi thin films at different sputtering powers and without substrate bias could increase the corrosion resistance of 304 stainless steel substrate. Using the substrate bias of −100 V in the fabrication of CoCrFeMnNi thin film decreased the corrosion current density and increased its polarization resistance.

Mapping the microstructure and the mechanical performance of a combinatorial Co–Cr–Cu–Fe–Ni–Zn high-entropy alloy thin film processed by magnetron sputtering technique

The Co–Cr–Cu–Fe–Ni–Zn compositional library was studied on a combinatorial high-entropy alloy thin film processed on a silicon substrate by magnetron sputtering technique. The thickness of the coating was between 2 and 3 μm while the lateral dimension was 10 cm. The chemical composition in the layer depended on the location and for each constituent element the concentration varied between 5 and 42 at.%. The phase composition and the microstructure were mapped using synchrotron X-ray diffraction, and the crystallite size as well as the density of lattice defects (dislocations and twin faults) were determined by diffraction line profile profile analysis. In addition, selected locations were studied by transmission electron microscopy. The influence of the chemical composition on the microstructure and the mechanical behavior was revealed. The mechanical performance was characterized by nanoindentation mapping which determined the hardness and the elastic modulus versus the element concentrations. It was found that the coating contains single phase face-centered cubic (FCC) and body-centered cubic (BCC) regions as well as an intermediate two-phase area. In the whole combinatorial sample, the microstructure consisted of nanocrystalline columns growing perpendicular to the coating surface and having pores between them. Due to the porosity, the hardness and the elastic modulus were relatively low despite the nanostructure and the very high defect density. The highest hardness (3.4 GPa) and elastic modulus (119 GPa) were measured in the BCC region with the chemical composition of 10%Co–38%Cr–13%Cu–27%Fe–5%Ni–7%Zn (at.%).

Microstructural stability and mechanical property of AlCrFeMoTi high-entropy amorphous alloy thin films under He+ ions irradiation

High-entropy amorphous materials have recently proved exceptional radiation resistance, showing potential as a candidate materials for nuclear industry applications. This study synthesized nearly equi-atomic AlCrFeMoTi high-entropy amorphous thin films with a thickness of about 499 nm using magnetron sputtering. The prepared films were subjected to low dose, 0.5 MeV He+ ion irradiation, with varying irradiation damage ranging from 0.01 to 0.1 displacement per atom (dpa). Increasing the irradiation dose led to a decrease in the radius of the inner diffraction halo (r) and an increase in the crystal-like order, indicating an irradiation-induced structural relaxation process within the amorphous matrix. This relaxation results in more efficient atomic packing, yielding a denser amorphous structure and enhanced hardness of AlCrFeMoTi high-entropy amorphous thin films. This study demonstrates that AlCrFeMoTi high-entropy amorphous thin films exhibit remarkable radiation resistance, with stable microstructure and mechanical properties under He+ irradiation, making them promising candidates for applications in the nuclear industry.

Structural Parameters and Behavior in Simulated Body Fluid of High Entropy Alloy Thin Films.

The structure, composition and corrosion properties of thin films synthesized using the Pulsed Laser Deposition (PLD) technique starting from a three high entropy alloy (HEA) AlCoCrFeNix produced by vacuum arc remelting (VAR) method were investigated. The depositions were performed at room temperature on Si and mirror-like polished Ti substrates either under residual vacuum (low 10-7 mbar, films denoted HEA2, HEA6, and HEA10, which were grown from targets with Ni concentration molar ratio, x, equal to 0.4, 1.2, and 2.0, respectively) or under N2 (10-4 mbar, films denoted HEN2, HEN6, and HEN10 for the same Ni concentration molar ratios). The deposited films' structures, investigated using Grazing Incidence X-ray Diffraction, showed the presence of face-centered cubic and body-centered cubic phases, while their surface morphology, investigated using scanning electron microscopy, exhibited a smooth surface with micrometer size droplets. The mass density and thickness were obtained from simulations of acquired X-ray reflectivity curves. The films' elemental composition, estimated using the energy dispersion X-ray spectroscopy, was quite close to that of the targets used. X-ray Photoelectron Spectroscopy investigation showed that films deposited under a N2 atmosphere contained several percentages of N atoms in metallic nitride compounds. The electrochemical behavior of films under simulated body fluid (SBF) conditions was investigated by Open Circuit Potential (OCP) and Electrochemical Impedance Spectroscopy measurements. The measured OCP values increased over time, implying that a passive layer was formed on the surface of the films. It was observed that all films started to passivate in SBF solution, with the HEN6 film exhibiting the highest increase. The highest repassivation potential was exhibited by the same film, implying that it had the highest stability range of all analyzed films. Impedance measurements indicated high corrosion resistance values for HEA2, HEA6, and HEN6 samples. Much lower resistances were found for HEN10 and HEN2. Overall, HEN6 films exhibited the best corrosion behavior among the investigated films. It was noticed that for 24 h of immersion in SBF solution, this film was also a physical barrier to the corrosion process, not only a chemical one.

Structure of refractory high entropy alloy and high entropy nitride thin films

Structure of refractory high entropy alloy and high entropy nitride thin films

The effect of Cr-content on the corrosion behavior of Ti0.5Mo0.5CoNiMnCrx high-entropy alloy thin films deposited by direct current magnetron sputtering

The present study aims to investigate the impact of Cr-content on the corrosion behavior of Ti0.5Mo0.5CoNiMnCrx high-entropy alloy thin films (HEATFs) fabricated through direct current magnetron sputtering. The microstructure and chemical composition of the HEATFs were characterized using grazing incidence X-ray diffraction (GIXRD), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), and transmission electron microscopy (TEM). The corrosion performance of the HEATFs was evaluated through electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization tests in 1 M NaCl and 0.5 M H2SO4 solutions. The GIXRD, FESEM, and TEM results confirmed a uniform amorphous structure of the HEATFs. EIS analysis and assessment of fitted parameters indicated the formation of a protective passive film during immersion in 1 M NaCl at the open circuit potential (OCP), in contrast to the behavior observed in 0.5 M H2SO4. Moreover, all the HEATFs exhibited superior corrosion resistance compared to the 316 L stainless steel substrate, as evidenced by the potentiodynamic polarization curves obtained in both 1 M NaCl and 0.5 M H2SO4 environments.

Nickel content-dependent microstructure and mechanical properties of TiZrNbHfNi high entropy alloy thin films

Alloying is known as an effective strategy to improve the mechanical properties of metallic materials. Here we show that the microstructure and mechanical behavior of a TiZrNbHf1.6 high entropy alloy film can be highly tuned by Ni addition. The newly designed TiZrNbHf1.6Nix (x = 0, 0.4, 1.2, 1.8, 2.5, 3.0, 4.6) alloy films are synthesized by co-sputtering Ti, Zr, Nb, Hf and Ni elemental targets. The microstructure and mechanical behavior of the alloy films are investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), and nano/micro-indentations. The microstructural analysis indicates that the TiZrNbHf1.6 film has a single body-centered cubic with columnar-nanograined structure. As Ni content increases to 0.4 or above, the films show a complete amorphous structure. Our theoretical analysis shows that the transition from the crystalline to the amorphous structure can be attributed to the large atomic radius difference and the change of the thermodynamic parameters (e.g., mixing entropy and mixing enthalpy) due to the Ni addition. Compared to the TiZrNbHf1.6 film with a hardness of 4.8 GPa, a hardness increase of 8–35% is achieved in the Ni-doped alloy films (5.2–6.5 GPa) as measured by nanoindentation. The elevated hardness may be attributed to the severe lattice distortion and the amorphous structure induced by the Ni addition. Furthermore, microindentation reveals a diversity of deformation behavior in those films with different Ni content. A homogeneous deformation (slight plastic pileup) occurred in the films with Ni content of 1.2 and 4.6, which is close to the deformation behavior of the crystal TiZrNbHf1.6 film. While the film with a Ni content of 1.8 exhibits a catastrophic cracking deformation. Finally, multiple shear banding dominates the deformation of these films with Ni content of 0.4, 2.5 and 3.0. Our findings demonstrate that ultrastrong and highly deformable amorphous high entropy alloy thin films can be developed by appropriate element addition, making them promising materials for corrosion and wear-resistant coatings.

Design of high-entropy films as ultra-violet light reflector

This study proposes the design and implementation of high-entropy alloy (HEA) thin films as materials for the reflector of deep ultraviolet light-emitting devices and marks the first application of HEA in optical field. In the material design phase, an Al-Co-Zn-Ni alloy is designed by considering the reflectivity, phase stability and binary formation energy. Reverse Monte Carlo calculation is employed to establish stable atomic structure. Frequency-dependent dielectric equations are derived from first principles calculations, with dielectric constants incorporating contributions from ions and electrons and combining classical Drude and Lorentz models. The dielectric equations yield optical constants that are used to calculate the reflectance. In the experimental phase, we systematically vary the aluminum content and prepare Al-Co-Zn-Ni thin films ranging from pure aluminum to equimolar compositions. In the deep ultraviolet region, the reflectance of thermally treated Al65Zn12Co12Ni11 and Al50Zn16Co17Ni17 thin films is found superior to that of gold by three times. Structural and crystalline changes with varying aluminum content are found, as well as intriguing phase separation and superlattice formation that persist until equimolar compositions. This unique nanoscale structural variation causes the Young's modulus and hardness of Al-Co-Zn-Ni thin films to initially increase and then decrease with decreasing aluminum content. There is a significant increase in the corrosion potential difference when reducing Al contents in Al-Co-Zn-Ni, indicating improved passivation effects as the equimolar composition is approached. By modulating the aluminum content, the nanoscale structure of Al-Co-Zn-Ni can be adjusted, thereby improving its optical, mechanical, corrosion resistance, and thermal stability properties. This demonstrates the high versatility of this material for practical optical applications.

Tuning microstructure and properties of MoNbTaWZr high entropy alloy films by adjusting the parameters in high power impulse magnetron sputtering

Within this study a series of MoNbTaWZr thin films were synthesized using high power impulse magnetron sputtering (HiPIMS) with varying the deposition parameters: duty cycle from 0.5 to 100 % (i.e. DC magnetron sputtering (DCMS)), Ar pressure from 0.5 to 3 Pa and pulse frequency from 25 to 200 Hz. The structure of the deposited films was analyzed by X-ray diffraction and scanning and transmission electron microscopy. In addition, the electrical resistivity and the residual stress of the films was determined. The influence of the deposition parameter variation on structure and properties of the MoNbTaWZr films is discussed on the established framework of film growth conditions achievable with HiPIMS and DCMS and how they can be influenced by adapting the deposition parameters. The performed work is intended to contribute to a comprehensive understanding about synthesis-structure-property relations for refractory high entropy alloy thin films while using MoNbTaWZr films as a model system.

Effect of nitrogen pressure on the fabrication of AlCrFeCoNiCu0.5 high entropy nitride thin films via cathodic arc deposition

In the past two decades, high entropy alloy (HEA) coatings have attracted great attention due to their superior mechanical properties, outstanding corrosion and oxidation resistance, and exceptionally high thermal stability. In comparison to HEA thin films, high entropy nitrides (HENs) exhibit higher mechanical strength and chemical inertness. In this work, AlCrFeCoNiCu0.5 HEA and HEN thin films were fabricated using a filtered cathodic arc. By regulating the deposition pressure from 0.0005 Pa (HEA thin film) to 0.05 Pa, the nitrogen concentration in each thin film was precisely controlled to tune the mechanical properties. Scanning transmission electron microscopy-energy dispersive spectroscopy revealed that the nitrogen concentration of the films was up to 21.2 at. % at the pressure of 0.05 Pa. The reduced effect of preferential sputtering increased aluminum concentration from 8.3 ± 1.5 to 12.9 ± 2.2 at. % as pressure increased up to 0.05 Pa. X-ray photoelectron spectroscopy further confirmed the formation of AlN and CrN at pressures of 0.01–0.05 Pa. The highest hardness and elastic modulus of the HEN film were 12.4 ± 0.6 and 347.3 ± 17.7 GPa, respectively, which were 84.8% and 131.4% higher than those of the HEA thin film.

Phase decomposition of AlCrFeCoNiCu0.5 HEA thin films by vacuum annealing

The most attractive advantages of high entropy alloy (HEA) thin films are their excellent properties, such as high strength and high corrosion and oxidation resistance, with a lower material cost. However, the thermal stability of the HEA thin films is always controversial. This is critical since the thermal stability of metals and alloys is closely related to the material's performance at high temperatures and also determines the application field of the material. The question of how will the nanocrystalline high entropy alloy thin film perform in terms of thermal stability needs to be clarified urgently. In this research, the thermal stability of AlCrFeCoNiCu0.5 HEA thin film fabricated by cathodic arc deposition was investigated at 500 °C as a function of time during vacuum annealing. X-Ray Diffraction (XRD), High-Resolution Transmission Electron Microscopy (HRTEM) and Transmission Kikuchi Diffraction (TKD) were applied to analyze the chemistry and microstructure of HEA thin films in detail. The results showed that there was no obvious change in the elemental compositions of the films after annealing, but the elemental distribution of the annealed films was different from the as-deposited film, especially at the film surface and film-substrate interface for the 24 h-annealed sample. The existence of the FeCo phase with B2 structure was a significant sign to demonstrate that the spinodal decomposition occurred in the single face-centered-cubic (FCC) phase matrix of the film during annealing. Simultaneously, the segregation of Cu and Cr near the film-substrate interface and the penetration of Ni and Cu towards the Si substrate were clearly observed. These unusual phenomena indicated that the thermal stability of HEA was not always excellent. Also, it was noticed that a few Kirkendall voids forming at the film-substrate interface after 24 h of annealing would affect the adhesion of the film. Additionally, heat recovery and recrystallization were achieved by 500 °C annealing, which were confirmed by the decrease of lattice parameter and the increase of grain size in the 24 h-annealed thin film. Furthermore, the hardness and elastic modulus of the thin films before and after annealing were measured by nanoindentation. The results showed all the thin films exhibited excellent mechanical properties, and the optimal hardness and elastic modulus of 7.7 ± 0.3 GPa and 183.9 ± 4.4 GPa were obtained after 3 h-annealing.

Introducing a new heterogeneous nanocomposite thin film with superior mechanical properties and thermal stability

High entropy alloy (HEA) films offer excellent mechanical properties due to their random solid solution structure. However, their large grain boundary volume fraction can cause thermal instability, resulting in phase decomposition that affects their high-temperature performance. Nevertheless, it remains an interesting question whether phase decomposition can be used as a processing tool to create new HEA materials. In this study, AlCrFeCoNiCu0.5 HEA thin films were fabricated and annealed at 500 °C for up to 72 h. The 72-hour annealed thin film exhibited a 30 % increase in mechanical properties, exceeding most other HEA thin films. Characterization using X-ray and electron microscopy revealed a decomposition-induced phase transformation, which produced four new phases, including Cu-rich FCC phase, Cr-rich BCC phase, and ordered B2 phase of AlNi and FeCo. The enhanced mechanical properties were due to back stress strengthening and BCC + B2 phase strengthening. The 72-hour annealed thin film also showed excellent thermal stability through a new round of annealing, exhibiting a low variation in microstructure and chemical composition after being annealed at 500 °C for 100 h.

Direct electrodeposition of CoFeNiMoW high entropy alloy thin films from aqueous medium

The direct electrodeposition of CoFeNiMoW high entropy alloy (HEA) thin films from aqueous medium is demonstrated. By employing a citrate-containing bath and varying the applied current density (ic), HEAs with different compositions are obtained. Specifically, the composition of the HEA thin film obtained at ic = 50 mA cm−2 is Co30Fe21Ni19Mo25W5. The physical characterization of the HEA thin films is performed by energy dispersive x-ray spectrometry (EDS), grazing incidence x-ray diffraction (GIXRD), and 57Fe Mössbauer spectroscopy. Results confirm the presence and composition of the multicomponent HEA thin films and highlight galvanostatic electrodeposition as a simple, versatile, and cost-effective technique to create these HEA thin films.

Utilizing cluster percolation theory to analyze electrical resistivity jumps in high-entropy alloy thin films containing small atoms

The high-entropy alloy thin films (HEATFs) with non-metal small atoms have obvious characteristics of adjustable properties. However, the mismatch phenomenon of phase-transition and electrical resistivity jump usually occur during the interstitial-filling. To explain this phenomenon, a new method is proposed that transforms the multi-color percolation of HEATFs to two-color percolation. The [N/O-M6] clusters with high electrical resistivity and [▫-M6] clusters with low electrical resistivity in (NbMoTaW)100-xNx and (NbMoTaWV)100-xOx films are equivalent to black and white spheres, respectively (M and ▫ ▫-M6]) reaches the face-centered-cubic and amorphous percolation thresholds of 0.198 and 0.27, respectively, a conductive percolation path is formed, contributing to a significant reduction in electrical resistivity. This work enables it possible to predict the composition at sudden change in electrical resistivity of HEATFs with non-metallic small atoms, which has great significance for the functional composition design.

Flexomagnetic Effect Enhanced Ferromagnetism and Magnetoelectrochemistry in Freestanding High-Entropy Alloy Films.

Freestanding thin films of functional materials enable the tuning of properties via strain and strain gradients, broadening their applications. Here, a systematic approach is proposed to fabricate freestanding CrMnFeCoNi high-entropy alloy (HEA) thin films by pulsed laser deposition using expansion-contraction of NaCl substrates and weak van der Waals interaction of the interface, which form wrinkles with inhomogeneous strain gradients when transferred to a viscous handle. We demonstrate that the nonuniform gradients of external strain (flexomagnetic effect) can induce the partial structural phase transition from FCC to BCC in the wrinkled HEA film, resulting in a 10-fold increase in its room-temperature saturation magnetization compared with the unstrained flat HEA film. Furthermore, after applying an external magnetic field, due to the different electron transfer behavior caused by the electron scattering in wrinkled and flat HEA films, their electrocatalytic magnetic responses showed a diametrically opposite picture. Our work provides a promising strategy for tuning physical and chemical properties via complex strained geometries.