Achieving a synergistic improvement in the strength and ductility of metallic materials has long been a central challenge in materials science. Dislocation mobility limits both properties, making it difficult to strike a balance between them. The advent of multi-principal element alloys (also known as high-entropy alloys) offers a promising solution to this issue. Compared with conventional solid solution strengthened alloys, multi-principal element alloys exhibit greater lattice distortion. Consequently, dislocation movement must overcome higher and more frequent energy fluctuations, which consumes more energy. This increase in flow stress with increasing strain allows certain alloys to achieve enhanced work hardening capacity, leading to simultaneous improvements in both strength and ductility. However, two critical scientific questions in this area warrant further investigation: (1) Are multi-principal element alloys purely ideal random mixed structures, or is standardizing their local or multi-level microstructures necessary to achieve optimal performance? (2) How can we effectively standardize and regulate the microstructures of multi-principal element alloys? This study addresses these questions by proposing the concept of using negative mixing enthalpy (negative-enthalpy) alloying to standardize and regulate the microstructure of multi-principal element alloys. This study systematically explores how negative-enthalpy alloying can synergistically enhance strength and ductility while revealing new mechanisms of strengthening and toughening. Negative-enthalpy alloying affects the microstructure of metallic materials through three main effects: bond energy and slow diffusion, local chemical ordering, and interface and size effects. This approach provides a novel framework for designing and processing the microstructures of high-strength, high-ductility metallic materials at the atomic scale.

Limited energy resources cannot meet the long-term developmental needs of human society. As such, nuclear fusion energy is considered a key solution for environmental protection and meeting future energy demands. However, to ensure the reliable operation of fusion reactors, addressing heat load damage to the divertor facing plasma in tokamak devices is crucial. The divertor, an indispensable core component of fusion devices, plays essential roles in these devices, including the removal of heat load generated via scraping layers and radiation and protection of the main vacuum chamber, auxiliary heating systems, and diagnostic systems, thereby ensuring the safe and stable operation of nuclear fusion reactors. Nevertheless, due to harsh operational conditions, the divertor is prone to damage, limiting the stable operation of long-pulse, high-parameter plasmas. W is critical in the divertor of fusion reactors, primarily owing to its high melting point, low physical sputtering rate, low deuterium retention, and excellent mechanical properties, allowing it to perform stably under extreme conditions. However, tungsten materials have several limitations, including a high ductile-brittle transition temperature, a low recrystallization temperature, and susceptibility to activation. Therefore, it is necessary to regulate, modify, and optimize these materials to enhance the performance of plasma-facing materials (PFMs). Such improvements aim to increase their resilience under extreme environments, minimize damage risks under high heat loads, and enhance heat load resistance, thereby ensuring the long-term stable operation of the divertor in fusion reactors and to meet future energy challenges. The working conditions of fusion reactors are extremely harsh, with the divertor region experiencing continuous heat load damage. It typically faces steady-state heat loads with peak values as high as 5-20 MW/m² and transient heat loads of up to ~2 GW/m². These heat loads can cause melting and cracking on both sides of the divertor cassette, posing a risk of reactor failure. Consequently, the study of the heat load damage behavior in tungsten-based PFMs as well as development of damage mitigation strategies have become hot topics in fusion research. This paper reviews current research efforts, both domestic and international, related to the damage behavior of pure tungsten, tungsten alloys, and dispersed phase-strengthened tungsten under heat load conditions. Additionally, it summarizes and forecasts the evolution of heat load damage in tungsten-based materials and presents strategies for damage mitigation, thereby providing a reference for future research endeavors.

With advancements in miniaturization and performance in advanced packaging technology, the diameter of Sn-based microbumps continues to shrink to the micrometer scale. Consequently, the current density passing through each solder bump increases exponentially as the radius reduces. This emphasizes the critical need to understand the behaviors and mechanisms of electromigration (EM) for the reliability evaluation and design of chip interconnects in integrated circuits. This study systematically summarizes and analyzes the physical nature, key influencing factors and research methods related to the electromigration of Sn-based microbumps. The EM characteristics during the solid-solid EM, including the polarity effect, reverse polarity effect and two-phase separation are reviewed. Similarly, the EM behaviors during the liquid-solid EM, including atomic migration, phase segregation, and phase dissolution, are systematically reviewed. The EM lifetime assessment models and their modifications are evaluated. Furthermore, this study summarizes methods to improve the EM reliability of Sn-based microbumps and outlines prospective research directions and analytical approaches to further improve their reliability in advanced electronic applications.

In the shipbuilding industry and coastal engineering, thick EH36 steel plates used in vertical construction generally require joining by high heat input electro-gas welding with matching flux-cored wire to enhance production efficiency and reduce construction time. However, high heat input welding can result in high peak temperatures and slow cooling rates, leading to coarse and deteriorated microstructures in the weld metal, thereby compromising the mechanical properties of the welded joint. Given the challenge of quantifying and controlling the composition, microstructure, and properties of weld metal due to complex metallurgical reactions during high heat input electro-gas welding, five CaF₂-TiO₂ fluxes were designed, prepared, and incorporated into flux-cored wires to join EH36 shipbuilding steels with a thickness of 30 mm. The effect of TiO₂ content on the composition, microstructure, inclusions, and properties of the weld metals was systematically studied. The results indicate that as the TiO₂ content in the fluxes increases, the hardness of the weld metal decreases, while impact toughness improves. During welding, the high-temperature arc causes greater decomposition of TiO₂, leading to increased O and Ti contents in the molten pool. Simultaneously, more Si and Mn are lost into the slag through the slag-metal interface. The reduction in alloying element content shifts the continuous cooling transformation curve toward the upper left, expanding the temperature range of the ferrite phase transformation from 755-578 ^oC to 780-595 ^oC. Increasing the O and Ti contents in the weld metals raises the number density of inclusions from 4289 mm^-2 to 5327 mm^-2. The synergistic effect of multiple factors promotes an increase in the volume fraction of acicular ferrite from 9.3% to 62.1%. The morphology of key microstructures in the weld metals transitions from parallel lath bainite to interwoven acicular ferrite, refining the grain size from (53 ± 14) μm to (10 ± 5) μm and increasing the volume fraction of high-angle grain boundaries from 41.8% to 59.2%, further enhancing the impact toughness of the weld metals.

The study of the dynamic behavior of materials under impact conditions is crucial in aerospace and defense industries. These materials are subjected to high speed and hyper-velocity impacts, high temperature, high pressure, and considerable deformation. Notably, many crystal-structured steel plates exhibit similar variability when subjected to impact conditions. A current and cutting-edge topic in contemporary research is the exploration of the microstructure properties of steel plates with various crystal structures under impact. This study aims to investigate the microstructural change of various crystalline structural steel materials under impact loads with high velocities. Two typical crystalline structural steels, 304 and Q345 stainless steels, were tested in impact tests using a two-stage light-gas pistol. The microstructure features of the steel plates under impact were characterized and examined using characterization techniques like XRD, EBSD, and TEM. Under impact conditions, the 304 stainless steel plate did not show any significant flanging phenomena at the macro level. However, there is a minor degree of ε-martensite transition and micro α'-martensite transformation that occurs on 304 stainless steel plates. Austenite and martensite have a similar K-S orientation relationship. Under the impact condition, the Q345 steel plate displays macro-level flipping properties but no overt micro-level phase transition. However, the diffraction peak on the {110} crystal plane substantially increases, the space between crystal planes narrows, and the {200} crystal plane shows a considerable diffraction peak shift to the right, creating the grains' preferred orientation. The Q345 steel plate exhibits considerable crystal structure delamination under impact, whereas 304 stainless steel did not display significant crystal structure elongation. The two types of steel plates have various macroscopic fracture modes owing to their differing crystal structures. Specifically, the Q345 steel demonstrates plastic fracture properties, whereas 304 stainless steel displays almost brittle fracture characteristics. The twin grain boundary of austenite is where martensite forms based on the calibration of electron diffraction spots.

Improvements in passenger safety and fuel efficiency are crucial issues in the automotive industry. The use of advanced high-strength steel (AHSS) in automotive parts has been suggested as a solution to these issues because it enables large weight reduction and good crash worthiness. Strength and ductility are the key mechanical properties of automotive AHSS. However, high strength is often accompanied by low ductility, resulting in the so-called strength-ductility trade-off dilemma. Currently, there is an increasing demand for automotive AHSS that exhibits a balance between strength and ductility. Lightweight and high-strength medium Mn steel (MMnS with a Mn mass fraction of 3%-12%), as a representative example of the third-generation automotive AHSS, has an excellent combination of strength and plasticity due to the effective usage of the coupled transformation-induced plasticity (TRIP) effect and twinning-induced plasticity (TWIP) effect of the metastable austenite constituent upon deformation. To further improve comprehensive mechanical properties, MMnS with a high Mn content were developed to increase the austenite fraction. Thus, a duplex structure with an ultrafine ferrite and austenite matrix was formed. However, Mn segregation is likely to occur in MMnS with increasing Mn content, especially in the cases of Mn > 10% (mass fraction), which considerably influences MMnS's performance. Therefore, the effects of Mn segregation on the overall mechanical properties, microstructure, and deformation mechanism of MMnS need to be elucidated in more details. In this paper, the influence of Mn segregation on the microstructure and mechanical properties of MMnS with an austenite-ferrite duplex structure and a nominal composition of 0.3C-11Mn-2.7Al-1.8Si-Fe was systemically investigated. Specifically, the underlying mechanism of Mn segregation that affects the mechanical and microstructural behavior of cold-rolled and annealed MMnS was analyzed. The results show that Mn segregation causes the formation of a Mn-rich banded structure, where the grain size of austenite is larger, austenite stability is higher, and fine ferrite is distributed more sparsely on the austenite matrix compared with the case without Mn segregation. The dominant plastic deformation mechanism of austenite in the non-Mn segregation zone involves martensitic transformation and twinning, leading to the coupled TRIP + TWIP effect, while the rate of martensitic transformation is higher than those without Mn segregation. However, the martensitic transformation is inhibited in the austenite of the Mn-rich structure because of its higher stability, limiting the TRIP effect. Consequently, the test MMnS with Mn segregation shows lower ductility and fracture resistance than those without Mn segregation; moreover, its finer austenite enhances the work-hardening capacity.

The corrosion and mechanical properties of austenitic stainless steels can be enhanced considerably by adding Nb. Newly developed Nb-stabilized austenitic stainless steels, such as 347HFG, 316Nb, TP310HCb, NF709, and HT-UPS, exemplify this advancement. The required Nb content varies across these steels. Prior research has indicated that in the as-cast microstructure of these steels, coarse and unevenly distributed primary NbC often forms, adversely affecting their mechanical and corrosion properties. Furthermore, this coarse primary NbC depletes the solid solution of Nb, which is counterproductive for fine secondary NbC precipitation. Notably, modifying the morphology and size of primary NbC through hot working and heat treatment is challenging. To enhance the microstructure and mechanical properties of Nb-stabilized austenitic stainless steel, this study investigated the effects of Nb content and homogenization treatment on these steels. The microstructure and tensile properties of cast austenitic stainless steel were analyzed using OM, SEM, TEM, and tensile test. The findings reveal that varying Nb content influences the precipitation of primary NbC and M₂₃C₆ carbides. In Nb-free steel, M₂₃C₆ carbides precipitate continuously at grain boundaries. This precipitation still occurs in steel with 0.30%Nb (mass fraction), alongside the formation of NbC + γ eutectic structures. Increasing Nb content to 0.90% can suppress M₂₃C₆ carbide precipitation, although the eutectic structures become more prevalent. A notable enhancement in yield strength accompanies an increase in Nb content to 0.90%. This improvement is attributed to the solid solution strengthening by Cr (due to suppressed M₂₃C₆ carbides) and Nb, grain boundary strengthening from refined grain sizes, and precipitation strengthening by secondary NbC. However, microcracks are easily nucleated at primary NbC/γ interface under plastic deformation, leading to rapid crack propagation along primary NbC networks and resulting in trench-like brittle fractures. This mechanism significantly reduces elongation. Post-homogenization treatment at 1250 ^oC alters the primary NbC morphology from rod-like to spherical/ellipsoid. This change increases the critical stress required for microcrack nucleation at NbC/γ interfaces, thereby inhibiting microcrack initiation. Additionally, the primary NbC networks transform from continuous to discontinuous distributions, impeding microcrack propagation. Consequently, this treatment significantly enhances elongation without compromising strength.

At present, the development of low-cost Ni-based single-crystal (SX) superalloys with excellent properties is urgently needed to address the increasing cost of advanced aero-engines. In this study, a novel low-cost, third-generation Ni-based SX superalloy containing 3%Re (mass fraction) was investigated to assess its oxidation behavior and γ′ phase degradation at 1120 ^oC. Results showed that during the first 5 h of oxidation, a continuous and uniform three-layer oxide film was formed on the surface of samples. Given the relatively thin oxide film, measured at approximately 5 μm, the experimental alloy followed sub-parabolic kinetics. Between 10 and 100 h of oxidation, the nucleation and propagation of cracks in the Al₂O₃ interlayer accelerated the spallation of protective oxide films. This event resulted in the increased oxidation of the matrix alloy, along with the formation of AlN and large areas in the oxidation reaction domain (ORD). These phenomena caused the transformation from sub-parabolic kinetics to linear kinetics. After 150 h of oxidation, a continuous and zigzagging Al₂O₃ layer was formed at the bottom of the ORD that could hinder the outward diffusion of alloy elements and the inward diffusion of oxygen. Consequently, the alloy gradually approached parabolic kinetics as the Al₂O₃ layer was thickened. In addition, the intense oxidation reaction on the surface accelerated the degradation of the γ′ phase and the precipitation of the topologically close pack phase near the surface. Therefore, the low bond strength between the surface oxide film and the alloy matrix primarily contributed to the deficiency of high-temperature oxidation resistance of this experimental alloy.

γ-TiAl based alloys are advanced structural materials use in the automotive and aerospace industries. Their notable characteristics, including low density, high specific yield strength, and exceptional resistance to creep and oxidation, make them highly viable for being used as structural components in high-temperature applications of internal combustion engines. The novel β-solidifying γ-TiAl alloy designed in this study demonstrated excellent oxidation resistance at temperatures of 750, 800, and 850 ^oC. However, research regarding the solid-state phase transformations and microstructure control of this alloy is lacking. The study of the phase transformation behavior and microstructural evolution of alloys is crucial for developing appropriate thermal processing and heat treatment techniques for β-solidifying γ-TiAl alloys. This work introduces a novel Ti-Al-Mn-Nb alloy, with a nominal composition of Ti-43Al-1.5Mn-3Nb-0.2Si-0.2C-0.1B (atomic fraction, %). Using Pandat software for thermodynamic calculations, along with techniques such as EPMA, TEM, EBSD, and XRD, an extensive and meticulous investigation of the microstructural transformations within the range from 1440 ^oC to 1000 ^oC for this innovative alloy was undertaken. The results indicate that the as-cast microstructure of the alloy comprises a lamellar colony (α₂/γ), grain γ phase, and a small amount of β_o. The solidification pathway of the alloy can be determined as follows: liquid→liquid + β→β→β + α→α→α + γ→(α₂ + γ)→(α₂ + γ) + β_o→(α₂ + γ) + β_o + γ_g. The temperature at which the alloy exists as a single β phase (T_β ) is approximately 1420 ^oC, while the decomposition temperature of γ phase (T_γ,solv) is approximately 1280 ^oC; additionally, the eutectoid transformation temperature (T_eut) is approximately 1160 ^oC. Slightly below T_{γ, solv}, the γ precipitated from the α phase exhibits a lamellar structure. The α and γ phases consistently demonstrate a Blackburn orientation relationship: (111) _γ //(0001){}_{{\alpha }_{\mathrm{2}}} and <\mathrm{1}\overline{\mathrm{1}}\mathrm{0}> _γ //<\mathrm{11}\overline{\mathrm{2}}\mathrm{0}>{}_{{\alpha }_{\mathrm{2}}}, respectively. The secondary β_o phase precipitated from the α phase appears as a block shape and follows the Burgers orientation relationship: (110){}_{{\beta }_{\mathrm{O}}}//(0001){}_{{\alpha }_{\mathrm{2}}} and <111>{}_{{\beta }_{\mathrm{O}}}//<\mathrm{11}\overline{\mathrm{2}}\mathrm{0}>{}_{{\alpha }_{\mathrm{2}}}. The Vickers hardness of the quenched microstructure of the novel alloy ranges between 385 and 512 HV. With an increase in the quenching temperature, there is an observable enhancement in the microhardness of the quenched microstructure. The martensite microstructure formed after quenching in the β single-phase area contributes to the hardness of 512 HV. This novel alloy encompasses the β and α single-phase areas; thereby holding significant implications for the development of novel, highly deformable, and high-temperature-resistant β-solidifying γ-TiAl alloys characterized with fully lamellar structures.

Magnesium alloy is the lightest metal structure material and has one of the highest specific strength among metals. Thus, it has great potential in many applications, such as aerospace and automobile industry, to reduce the weight of components. However, magnesium alloys have very poor corrosion resistance that hinders their industrial application. Thus, several methods have been explored to improve the corrosion resistance of magnesium alloy to promote its application in industries such as automotive, aerospace, and electronics where lightweight materials are required. In this study, friction stir processing (FSP) has been applied to modify the microstructure of Mg-5Zn alloy to increase its corrosion resistance, which is a type of magnesium alloy used widely but has relatively poor corrosion resistance. Herein, three tools with different shoulder diameters of 14, 17, and 20 mm were selected to conduct FSP on the as-cast Mg-5Zn alloy. The microstructure has been observed and corrosion behavior has been investigated. The results reveal that the coarse grains of as-cast Mg-5Zn alloy are considerably refined by FSP treatment. The grain size reduces from hundreds of micrometers to a few micrometers. Furthermore, the coarse secondary phase in as-cast alloy is broken into small particles and distributed uniformly in the base material after FSP. Additionally, strong basal plane (0001) texture and low dislocation density have been observed in these FSP-treated samples, which are beneficial for increasing the corrosion resistance of magnesium alloy. Moreover, the size of the secondary phase increases with the increase of shoulder diameter, which leads to the increase in local cathode/anode area ratio, and the corrosion resistance of the three FSP-treated samples gradually reduces to 1520, 247, and 111 Ω·cm², respectively. Notably, under the FSP treatment at 800 r/min rotation speed, 40 mm/min traveling speed, and 0.3 mm plunge depth, when the tool with a shoulder diameter of 14 mm is employed, the precipitates in the Mg-5Zn alloy gets sufficiently fragmented and evenly dispersed, along with a relatively low dislocation density. The average corrosion current density of this friction stir processed sample in a 3.5%NaCl aqueous solution is reduced to 4.11 × 10^-6 A/cm² compared to that of the as-cast alloy (3.15 × 10^-5 A/cm²).

Zirconium alloys are considered as important nuclear reactor structural materials owing to their low thermal neutron absorption cross-section, good corrosion resistance, and good mechanical properties in high-temperature and high-pressure water. However, under high temperature and corrosion conditions, an oxide film forms on the surface of zirconium alloys, and its growth rate increases rapidly when the thickness is 2-3 μm, leading to a transition in corrosion kinetics, which limits its service life in the reactor. In this study, the transformation of zirconia from tetragonal (t-ZrO₂) to monoclinic (m-ZrO₂) and the crack propagation behavior in the oxidation layer on zirconium alloys have been investigated using phase-field simulation. During the transformation of t-ZrO₂ to m-ZrO₂ in the oxide film, the t-ZrO₂ matrix undergoes compressive and tensile stresses along the long and short axes of the m-ZrO₂ precipitate, respectively, whereas the m-ZrO₂ precipitate primarily undergoes compressive stress during the transformation. Moreover, the stresses increase with the growth of the m-ZrO₂ grains. The simulations of crack evolution reveal that the cracks in the oxidation layer parallel to the oxide-metal interface expand under applied tensile stress perpendicular to the interface. Such cracks may connect with other isolated cracks and defects forming a defect layer. Upon extending to the oxide-metal interface, surface cracks perpendicular to the interface bifurcate in the oxide rather than penetrate into the metal matrix, which facilitates the peeling off of the oxidation layer from the substrate.

Ni-based single-crystal superalloys weaken or even eliminate the influence of weak grain boundaries at high temperatures and contain \ge 60% (volume fraction) of L1₂-type coherent ordering γ'- Ni₃(Al, Ti) precipitation strengthening phase. These superalloys exhibit excellent properties at high temperatures such as, high resistance to oxidation, creep, and fatigue resistance, making them the preferred materials for manufacturing advanced aviation engine turbine blades. The inner cavity structure of engine turbine blades has become complex with the rapid development of the engine manufacturing industry, making investment casting technology as a key technology in blade production. Si-based ceramics are selected as core materials owing to their low thermal expansion coefficient, good dimensional stability, and easy solubility. However, during pouring, active elements such as Hf, Al, and Cr, in the superalloy liquid, undergo thermo-physicochemical and thermomechanical infiltration with the cores when they come in contact with Si-based ceramic cores for extended period at high temperatures. This results in interface reactions and sand formation on the casting surface, thereby reducing the quality of the blade's inner surface and increasing subsequent processes such as eliminating the reaction layer through certain chemical methods. To suppress the interface reaction between the superalloy liquid and Si-based ceramic cores during blade casting and improve the surface quality of the blade inner cavity, the effect of Al₂O₃ coating on the surface of Si-based ceramic cores were investigated using the multi-arc ion plating method. Furthermore, the effect of Al₂O₃ coating on the interface reaction and wettability between Si-based ceramic cores and the superalloy were explored using the in situ droplet method. The surface quality, morphology, element distribution, and reaction products of the interface reaction were analyzed via optical profilometry, SEM, and XRD, respectively. It has been found Al₂O₃ and silicides are generated in few areas at the bottom of the superalloy after high-temperature contact between the Al₂O₃-coated Si-based ceramic cores and superalloy melt. However, a continuous and dense Al₂O₃ reaction layer is formed at the bottom of the superalloy after contact between the unmodified Si-based ceramic cores and superalloy melt. The wetting angles of the superalloy melt on the Al₂O₃-coated and unmodified Si-based ceramic cores are 89.1° and 100.4°, respectively, indicating that the wettability is substantially improved by the Al₂O₃ coating. Results indicate that applying Al₂O₃ coating on Si-based ceramic cores can effectively suppress the interface reaction between Ni-based single-crystal superalloy and Si-based ceramic cores and improve the filling ability of the superalloy liquid during casting.

The use of synchrotron radiation X-ray imaging, with its high spatiotemporal resolution and strong penetration capabilities, holds significant promise for the in situ observation of three-dimensional microstructure evolution during the solidification of superalloy melts. However, the conventional computed tomography (CT) imaging technique has limitations for capturing the dynamic solidification of superalloy melts because of the limitations of in situ solidification equipment. This work introduces a synchrotron radiation X-ray stereo imaging technique that facilitates the swift acquisition of three-dimensional spatial data. Based on the principles of binocular parallax, the stereo imaging method leverages projections obtained from two distinct angles to derive depth information about a specific region of interest. This approach boasts notable enhancements in data acquisition speed and image reconstruction when compared with CT techniques. Notably, this work introduces the relationship between binocular projection disparity and depth information and it validates the method's effectiveness by using a static spiral wire sample with a known depth relationship. The experimental results unequivocally establish that the proposed method offers high-resolution capabilities in lateral and longitudinal directions. Finally, the X-ray stereo imaging technique is successfully deployed for the three-dimensional characterization of the solidification process in superalloy melts. It effectively overcomes the challenges posed by the in situ heating device that hinder conventional CT imaging, facilitating the successful reconstruction of the orientation relationship of the solidified microstructure in the thickness direction.

The equiatomic FeCoNi medium-entropy alloy (MEA) demonstrates promising attributes as a soft-magnetic material, including high saturation magnetization, high Curie temperature, and excellent ductility. However, its practical applications are constrained by relatively low yield and ultimate strengths. Recent studies explored strengthening FeCoNi alloy through the addition of other alloying elements or nanosized oxide particles (e.g., Al, Ti, Ta, and Y₂O₃). Although these additions often result in decreased saturation magnetization, they adversely affect the soft-magnetic properties. In this study, a heterostructured FeCoNi MEA, with approximately 49% (volume fraction) recrystallization, is achieved through annealing treatment. The influence of this heterostructure on mechanical and soft-magnetic behaviors of the MEA is systematically investigated. The results indicate that the heterostructured alloy maintains a specific saturation magnetization comparable to the fully-recrystallized version, approximately 152.5 A·m²/kg. Its coercivity, at 205.3 A/m, is lower than the non-recrystallized alloy (242.2 A/m) but higher than the fully recrystallized version (79.8 A/m). Magneto-optical Kerr analysis reveals that recrystallized zones in the heterostructure rapidly respond to external magnetic field changes, whereas non-recrystallized zones strongly interact with Bloch walls, pinning domain movement and thereby increasing coercivity. Furthermore, the heterostructured alloy exhibits enhanced mechanical properties: yield strength (σ_y) at 467 MPa, ultimate tensile strength (σ_u) at 610 MPa, and total elongation (δ) at 30%. This performance surpasses that of fully non-recrystallized (σ_y = 772 MPa, δ = 15%) and fully recrystallized (σ_y = 232 MPa, δ = 43%) alloys. These improved mechanical properties are partly attributable to long-range back stress, arising from the combination of soft recrystallized and strong non-recrystallized zones. This stress, produced by the strain gradient in the heterostructure, impedes geometrically necessary dislocations from slipping and enhances deformation compatibility, thereby preventing premature fracture. According to Ashby-type maps, the proposed heterostructured FeCoNi MEA bridges the gap between traditional soft-magnetic alloys and novel FeCoNi-based alloys in terms of soft-magnetic and mechanical properties.