Acta MaterialiaPub Date : 2024-11-18DOI: 10.1016/j.actamat.2024.120580
Zide Yu, Feiyu Su, Ao Tian, Xinchun Xie, Zijia Xu, Jian Fu, Ruzhong Zuo
{"title":"Elaborately-designed high-performance BiFeO3-PbTiO3 ceramics through refreshing phase boundary","authors":"Zide Yu, Feiyu Su, Ao Tian, Xinchun Xie, Zijia Xu, Jian Fu, Ruzhong Zuo","doi":"10.1016/j.actamat.2024.120580","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120580","url":null,"abstract":"The development of high-performance BiFeO<sub>3</sub>-PbTiO<sub>3</sub> (BF-PT) piezoelectric compositions is highly desirable, but still challenged due to their high Curie temperature (<em>T<sub>c</sub></em>), large lattice distortion and octahedral tilt induced large antiferrodistortion in rhombohedral-tetragonal phase (R3c-P4mm) coexisted compositions. Here, a dual strategy by introducing the pseudo-cubic (Pc) phase in place of the R3c phase, and adjusting the lattice distortion of P4mm phase was realized in 0.60Bi<sub>0.95</sub>La<sub>0.05</sub>FeO<sub>3</sub>-(0.40-x)PbTiO<sub>3</sub>-xBaTiO<sub>3</sub>, where a large piezoelectric coefficient <em>d<sub>33</sub></em> of ∼410 pC/N, a high <em>T<sub>c</sub></em> of ∼416 °C as well as a good thermal stability can be achieved at x=0.20 composition. The structural analyses indicate that the superior piezoelectric activity should be associated with several factors including the coexistence of tetragonal (T) and Pc phases without octahedral tilt, the field-induced reversible T-Pc transition and the optimized <em>c/a</em> ratio. More pronouncedly, the extrinsic piezoelectric response induced by significantly enhanced domain wall motion contributes to almost ∼70 % of the quasi-static <em>d<sub>33</sub></em> value. Moreover, the robust domain texture up to ∼400 °C is responsible for its good thermal stability. These merits suggest giant potentials of the elaborately-designed composition as high-temperature piezoelectric materials.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"21 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142665416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta MaterialiaPub Date : 2024-11-17DOI: 10.1016/j.actamat.2024.120576
Yeongwoo Son, Stanislav Udovenko, Sai Venkatra Gayathri Ayyagari, John Barber, Kae Nakamura, Christina M. Rost, Nasim Alem, Susan Trolier-McKinstry
{"title":"Polarization Stability and Its Influence on Electrocaloric Effects of High Entropy Perovskite Oxide Films","authors":"Yeongwoo Son, Stanislav Udovenko, Sai Venkatra Gayathri Ayyagari, John Barber, Kae Nakamura, Christina M. Rost, Nasim Alem, Susan Trolier-McKinstry","doi":"10.1016/j.actamat.2024.120576","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120576","url":null,"abstract":"In principle, the configurational entropy inherent in High Entropy Oxides (HEOs) could facilitate large electrocaloric effects (ECE) by promoting polar entropy. In this study, it is demonstrated that the time stability of the remanent polarization can be tuned via B-site disorder in High Entropy Perovskite Oxides (HEPO) films. Eight HEPO powders were synthesized; the propensity for perovskite phase formation was consistent with the Goldschmidt tolerance factor. While entropic contributions stabilize HEPO, they do not fully predict the stabilization. Relative dielectric permittivities between 2000 to 600 can be achieved for the B-site disordered HEPO films with loss tangents below 6% at room temperature. All films showed similar polarization-electric field loops with maximum polarization up to 48 <span><span style=\"\"></span><span data-mathml='<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow is=\"true\"><mi is=\"true\">&#x3BC;</mi><mi mathvariant=\"normal\" is=\"true\">C</mi></mrow></math>' role=\"presentation\" style=\"font-size: 90%; display: inline-block; position: relative;\" tabindex=\"0\"><svg aria-hidden=\"true\" focusable=\"false\" height=\"2.548ex\" role=\"img\" style=\"vertical-align: -0.697ex;\" viewbox=\"0 -796.9 1326 1096.9\" width=\"3.08ex\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"><g fill=\"currentColor\" stroke=\"currentColor\" stroke-width=\"0\" transform=\"matrix(1 0 0 -1 0 0)\"><g is=\"true\"><g is=\"true\"><use xlink:href=\"#MJMATHI-3BC\"></use></g><g is=\"true\" transform=\"translate(603,0)\"><use xlink:href=\"#MJMAIN-43\"></use></g></g></g></svg><span role=\"presentation\"><math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow is=\"true\"><mi is=\"true\">μ</mi><mi is=\"true\" mathvariant=\"normal\">C</mi></mrow></math></span></span><script type=\"math/mml\"><math><mrow is=\"true\"><mi is=\"true\">μ</mi><mi mathvariant=\"normal\" is=\"true\">C</mi></mrow></math></script></span> cm<sup>−2</sup> and a remanent polarization <span><span style=\"\"></span><span data-mathml='<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mo is=\"true\">&#x2265;</mo></math>' role=\"presentation\" style=\"font-size: 90%; display: inline-block; position: relative;\" tabindex=\"0\"><svg aria-hidden=\"true\" focusable=\"false\" height=\"2.086ex\" role=\"img\" style=\"vertical-align: -0.466ex;\" viewbox=\"0 -697.5 778.5 898.2\" width=\"1.808ex\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"><g fill=\"currentColor\" stroke=\"currentColor\" stroke-width=\"0\" transform=\"matrix(1 0 0 -1 0 0)\"><g is=\"true\"><use xlink:href=\"#MJMAIN-2265\"></use></g></g></svg><span role=\"presentation\"><math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mo is=\"true\">≥</mo></math></span></span><script type=\"math/mml\"><math><mo is=\"true\">≥</mo></math></script></span> 20 <span><span style=\"\"></span><span data-mathml='<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow is=\"true\"><mi is=\"true\">&#x3BC;</mi><mi mathvariant=\"normal\" is=\"true\">C</mi></mrow","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"117 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142665418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Grain boundary segregation spectrum in basal-textured Mg alloys: From solute decoration to structural transition","authors":"Anumoy Ganguly, Hexin Wang, Julien Guénolé, Aruna Prakash, Sandra Korte-Kerzel, Talal Al-Samman, Zhuocheng Xie","doi":"10.1016/j.actamat.2024.120556","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120556","url":null,"abstract":"Mg alloys are promising lightweight structural materials due to their low density and excellent mechanical properties. However, their limited formability and ductility necessitate improvements in these properties, specifically through texture modification via grain boundary segregation. While significant efforts have been made, the segregation behavior in Mg polycrystals, particularly with basal texture, remains largely unexplored. In this study, we performed atomistic simulations to investigate grain boundary segregation in dilute and concentrated solid solution Mg-Al alloys. We computed the segregation energy spectrum of basal-textured Mg polycrystals, highlighting the contribution from specific grain boundary sites, such as junctions, and identified a newly discovered bimodal distribution which is distinct compared to the conventional skew-normal distribution found in randomly-oriented polycrystals. Using a hybrid molecular dynamics/Monte Carlo approach, we simulated segregation behavior at finite temperatures, identifying grain boundary structural transitions, particularly the varied fraction and morphology of topologically close-packed grain boundary phases when changing thermodynamic variables. The outcomes of this study offer crucial insights into basal-textured grain boundary segregation and phase formation, which can be extended to other relevant Mg alloys containing topologically close-packed intermetallics.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"8 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142665420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta MaterialiaPub Date : 2024-11-17DOI: 10.1016/j.actamat.2024.120577
{"title":"Grain boundary nanochemistry and intergranular corrosion of Fe-0.01wt.%P alloy: Roles of elemental segregations and misorientation","authors":"","doi":"10.1016/j.actamat.2024.120577","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120577","url":null,"abstract":"The grain boundary (GB) segregation of alloying elements in an ultralow carbon Fe–P alloy was investigated at different annealing temperatures (500°C,…","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"80 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142665486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta MaterialiaPub Date : 2024-11-17DOI: 10.1016/j.actamat.2024.120552
Jinxin Yu, Alfonso H.W. Ngan, David J. Srolovitz, Jian Han
{"title":"Mesoscale description of interface-mediated plasticity","authors":"Jinxin Yu, Alfonso H.W. Ngan, David J. Srolovitz, Jian Han","doi":"10.1016/j.actamat.2024.120552","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120552","url":null,"abstract":"Dislocation-interface interactions dictate the mechanical properties of polycrystalline materials through dislocation absorption, emission, reflection, and interface sliding. We derive a mesoscale interface boundary condition to describe these, based on bicrystallography and Burgers vector reaction/conservation. The proposed interface boundary condition is built upon Burgers vector reaction kinetics and is applicable to any type of interfaces in crystalline materials with any number of slip systems. This approach is applied to predict slip transfer for any crystalline interface and stress state; comparisons are made to widely-applied empirical methods. The results are directly applicable to many existing dislocation plasticity simulation methods.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"31 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142665464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta MaterialiaPub Date : 2024-11-17DOI: 10.1016/j.actamat.2024.120555
Houssam Kharouji, Vincent Taupin, Julien Guénolé
{"title":"On the atomistic origin of internal length scale in strain-gradient plasticity models: The case of grain boundary structures and energies","authors":"Houssam Kharouji, Vincent Taupin, Julien Guénolé","doi":"10.1016/j.actamat.2024.120555","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120555","url":null,"abstract":"The mechanical behavior of polycrystalline materials is controlled by microstructural size effects such as grain size or precipitate size. Various models of strain gradient plasticity have been proposed to capture such size effects, many of which have incorporated geometrically-necessary dislocation (GND) densities to introduce characteristic internal lengths. Recent developments have focused on models that incorporate a GND density into the internal energy functional. In such models, one needs to physically justify the functional form chosen and quantify the inherent internal length parameter. Our present study aims at probing relevant forms and internal length values in the case of grain boundary (GB) atomistic structures and core energies. We use an atomistic-to-continuum crossover approach that predicts an atomistic structure dependent GB energy by molecular static simulations, which is then recovered at the continuum-level by using a strain gradient, atomistically informed, field dislocation mechanics fast Fourier transform model. This allows (i) delineating the atomistic structure of GBs using an equivalent Nye GND density, and (ii) capturing the associated continuous elastic fields in the GB core area. We probe (i) a generalized non-quadratic GND density dependent energy functional to account for the core energy of defects, and (ii) elucidate the contributions of core versus elastic energy to the overall GB excess energy. We investigate and discuss the possible relevant choices for the energy functional form, as well as the physical origin of the inherent internal length parameter and its dependence to the types of grain boundaries, atomistic structures, and spatial resolution.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"13 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142645854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta MaterialiaPub Date : 2024-11-15DOI: 10.1016/j.actamat.2024.120562
Yuanhui Su, Yu Huan, Wang Liu, Mengyue Ma, Jinkai Li, Tao Wei, Yunhui Huang, Kevin Huang
{"title":"Color-coding real-time detection for the health of lithium-ion batteries","authors":"Yuanhui Su, Yu Huan, Wang Liu, Mengyue Ma, Jinkai Li, Tao Wei, Yunhui Huang, Kevin Huang","doi":"10.1016/j.actamat.2024.120562","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120562","url":null,"abstract":"Lithium-ion batteries (LIBs) are pivotal energy devices in our daily lives, yet ensuring the quality and health of LIBs throughout their manufacturing and application processes remains a significant challenge. Here we propose a universal “color-coding” technique to indicate the health of LIBs, by which specific property characteristic and evolution inside LIBs can be unfolded. By defining the standard color coding for the entire manufacturing and application processes of LIBs, we show the change in material characteristics during various processes can be described by variations in standard color coding. Therefore, by establishing a universal color-property database, the proposed “color-coding” method has potential to be used as a practical tool to ensure the quality of materials and healthy operation of batteries.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"17 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta MaterialiaPub Date : 2024-11-15DOI: 10.1016/j.actamat.2024.120569
N.F. Shkodich, T. Smoliarova, H. Ali, B. Eggert, Z. Rao, M. Spasova, I. Tarasov, H. Wende, K. Ollefs, B. Gault, M. Farle
{"title":"Effect of high energy ball milling, heat treatment and spark plasma sintering on structure, composition, thermal stability and magnetism in CoCrFeNiGax (x = 0.5; 1) high entropy alloys","authors":"N.F. Shkodich, T. Smoliarova, H. Ali, B. Eggert, Z. Rao, M. Spasova, I. Tarasov, H. Wende, K. Ollefs, B. Gault, M. Farle","doi":"10.1016/j.actamat.2024.120569","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120569","url":null,"abstract":"Nanocrystalline (∼10 nm) singe-<em>fcc</em> CoCrFeNiGa<sub>x</sub> (x = 0.5, 1.0) high entropy alloy (HEA) particles with excellent structural and compositional homogeneity were prepared from elemental powders using a single-step, short-term (190 min) high energy ball milling (HEBM) at room temperature (RT). Both HEA powders exhibit paramagnetic behaviour at RT with a small ferromagnetic contribution at low fields (the saturation magnetization <em>M</em><sub>s</sub>= 4.5 Am<sup>2</sup>/kg – 7.5 Am<sup>2</sup>/kg; the average Curie temperature <em>T</em><sub>c</sub> = 130 K – 150 K). They are thermally stable up to 1295 K–1305 K despite the low melting Ga (302.9 K). Heat treatment up to 1000 K enhances <em>M</em><sub>s</sub> to 59.9 Am<sup>2</sup>/kg and <em>T</em><sub>c</sub> to 740 K for the CoCrFeNiGa HEA powder due to an irreversible <em>fcc</em>→<em>bcc</em> structural transformation, whereas the magnetic properties of CoCrFeNiGa<sub>0.5</sub> do not show this enhancement. In-situ TEM heating reveals nanosized σ-phase Cr-rich precipitates (< 50 nm) at 875 K only for the CoCrFeNiGa HEA powder. Spark plasma sintering (SPS) of powders produces homogeneous nanocrystalline bulk HEAs. SPS at 1073 K of the CoCrFeNiGa<sub>0.5</sub> powder increased the crystallinity of the <em>fcc</em> phase. Three-dimensional local compositional mapping at atomic resolution by atom probe tomography indicates a homogeneous distribution of all elements. Bulk HEAs exhibit similar magnetic behavior to heat-treated HEA powders. Combining HEBM and SPS yields homogeneous bulk HEAs with low-melting Ga and enhanced structural, composition, thermal stability, as well as improved magnetic properties (<em>M</em><sub>s</sub> = 55Am<sup>2</sup>/kg and <em>T</em><sub>c</sub> = 750 K), which 45% and 47 K higher, respectively, compared to conventional melting approaches.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"136 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta MaterialiaPub Date : 2024-11-15DOI: 10.1016/j.actamat.2024.120571
Tian-Le Cheng, Fei Xue, Yinkai Lei, Richard P. Oleksak, Ömer N. Doğan, You-Hai Wen
{"title":"Phase-Field Modeling of Thermally-Grown Oxide and Damage Evolution in Environmental Barrier Coatings","authors":"Tian-Le Cheng, Fei Xue, Yinkai Lei, Richard P. Oleksak, Ömer N. Doğan, You-Hai Wen","doi":"10.1016/j.actamat.2024.120571","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120571","url":null,"abstract":"Silicon carbide-based ceramic matrix composites protected by environmental barrier coatings (EBCs) present a promising materials solution for next-generation gas turbines. Developming more robust and efficient EBCs is therefore of significant technological importance. During the service in high-temperature oxidative environments, there is a thermally grown oxide (TGO) layer, spontaneously formed in the EBC system. TGO is recognized as a critical factor for the degradation and failure of EBCs, yet the detailed mechanisms of TGO growth and its effect on EBC failure remain unclear. In this study we develop a comprehensive chemo-mechano-phase-field model to simulate growth of the TGO in EBCs, factoring in creep and deformation, and especially the cracking behaviors. The volume expansion due to TGO growth and the resulting large inelastic deformation are addressed by using our recently developed, so-called incremental realization of inelastic deformation (IRID) algorithm, in combination with an adapted Hu-Chen spectral solver for elasticity. Simulations of TGO growth are performed considering different growth modes of TGOs determined mainly by the ratio of oxidant permeability in the topcoat to that in the TGO itself. Large-scale three-dimensional (3D) simulations are performed to model the formation of interconnecting vertical/channel cracks (often called ‘mud cracks’). The simulated crack morphology are in excellent agreement with the experimental observations from the literature. The simulations also provide insights into the cracking of EBCs and its dependence on the structure and constituent properties of the coating system. These results demonstrate the developed damage model can be a useful tool for design of more durable EBCs.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"21 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Acta MaterialiaPub Date : 2024-11-14DOI: 10.1016/j.actamat.2024.120572
Hongchao Li, Jun Wang, Wenyuan Zhang, Jiawang Zhao, Jinshan Li, M.W. Fu
{"title":"Achieving superior ductility with ultrahigh strength via deformation and strain hardening in the non-recrystallized regions of the heterogeneous-structured high-entropy alloy","authors":"Hongchao Li, Jun Wang, Wenyuan Zhang, Jiawang Zhao, Jinshan Li, M.W. Fu","doi":"10.1016/j.actamat.2024.120572","DOIUrl":"https://doi.org/10.1016/j.actamat.2024.120572","url":null,"abstract":"Developing metallic structural materials with ultra-high strength and exceptional ductility remains a significant challenge due to the trade-off between both properties. This study presents a heterogeneous-structured high-entropy alloy achieving a superior combination of strength and ductility compared to the reported heterogeneous-structured HEAs through deformation and strain hardening in the non-recrystallized regions. The cold rolling followed by annealing at 760°C resulted in a heterogeneous microstructure consisting of a small fraction of ultrafine recrystallized grains and extensive non-recrystallized regions, with a significant amount of L1<sub>2</sub> precipitates throughout the alloy. The architected microstructure led to a significant enhancement of yield strength through mechanisms including dislocation strengthening, L1<sub>2</sub> strengthening, and grain boundary strengthening. During the deformation, the non-recrystallized regions accommodated substantial strain through the reactivation of pre-existing deformation bands and the synergistic deformation of the FCC and L1<sub>2</sub> phases, thereby markedly enhancing ductility. Moreover, the metastable FCC matrix underwent FCC→BCC phase transformation, leading to the formation of numerous short-range BCC domains, which further contributed to the pronounced strain hardening. Consequently, the alloy annealing at 760 °C achieved a yield strength of 1.73 GPa, an ultimate strength of 2.05 GPa, and an elongation of 21.0%. This study underscores a novel strategy for the concurrent enhancement of strength and ductility and provides valuable insights for the design of high-performance alloys.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"45 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142637682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}