Acta Materialia最新文献

{"title":"Hybrid machine learning and finite element modeling for accurate prediction of sintering-induced deformation in material extrusion additive manufacturing","authors":"Sri Bharani Ghantasala,&nbsp;Gurminder Singh","doi":"10.1016/j.actamat.2025.121225","DOIUrl":"10.1016/j.actamat.2025.121225","url":null,"abstract":"<div><div>The current study developed a physics-based, data-driven finite element analysis (FEA) model using commercially available software to predict the shrinkage and deformation of copper specimens fabricated by material extrusion 3D printing (ME3DP) during the pressureless sintering process. Identifying shrinkage and deformation prior to designing the 3D CAD model helps designers optimize and adjust the component geometry, considering the sintering effects. In this regard, two datasets were captured: one from the developed phenomenological model and the other from the experimental outcomes of the sintering process. The artificial neural network (ANN) being a machine learning (ML) technique, was configured using the complete dataset by optimizing and identifying the most suitable network parameters to determine the relative density during the sintering of ME3DP copper specimens. The configured ANN was rebuilt and used as a constitutive equation to predict the shrinkage and deformation of copper specimens in COMSOL Multiphysics by modifying the existing constitutive laws. The results obtained from the experiments, FEA, and ML-FEA models were compared for two different shapes: cubic and I-section geometries. Additionally, the stresses evolved in the cube and I-section copper specimens captured by the FEA and ML-FEA models are presented. Furthermore, Shapley additive explanations (SHAP), an interpretability tool, was incorporated to quantitatively analyze the influential order of the input features and their contribution to the prediction of relative density.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121225"},"PeriodicalIF":8.3,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144237441","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":"Thermodynamics of grain boundary segregation transition and their relevance for liquid metal embrittlement in Fe-Zn system","authors":"Yuki Ikeda ,&nbsp;Theophilus Wallis ,&nbsp;Robert Maaß ,&nbsp;Reza Darvishi Kamachali","doi":"10.1016/j.actamat.2025.121134","DOIUrl":"10.1016/j.actamat.2025.121134","url":null,"abstract":"<div><div>Grain boundaries (GBs) are common sites of failure in polycrystalline materials. Recently, a massive Zn segregation transition at Fe GBs was discovered and shown to act as a potent precursor of liquid metal embrittlement (LME) in the Fe-Zn system (Kamachali et al., Scripta Materialia 238 (2024) 115758). In this study, we elaborate on how temperature, GB type and the chemo-structurally coupled phase decomposition at the GB impact this segregation transition. CALPHAD and atomistic simulation data were utilized as inputs to conduct quantitative density-based thermodynamic modeling and phase-field simulations across various GBs, alloy compositions, and temperatures. We reveal that once the segregation transition becomes possible, the GB structural variation stabilizes spinodally formed Zn-rich phases within the GB region, with a higher tendency in disordered GBs. GB phase diagrams were constructed to identify and analyze the range of critical temperatures and alloy compositions associated with the segregation transition. The phase diagrams reveal that the miscibility gap for more disordered GB expands and, although the segregation transition is inevitable and occurs for all GBs, the barrier to triggering it is lower for more disordered GBs. Based on our thermodynamic analyses, potential processing modifications and GB engineering strategies for mitigating segregation-induced LME are thoroughly discussed.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121134"},"PeriodicalIF":8.3,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144236813","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":"Enabling high strength yet ductility in a refractory high-entropy alloy through oxygen-nitrogen synergistic effect","authors":"Xiaodi Wang ,&nbsp;Tianxin Li ,&nbsp;Dingfeng Xu ,&nbsp;Yuan Wu ,&nbsp;Qianqian Wang ,&nbsp;Peter K. Liaw ,&nbsp;Yiping Lu","doi":"10.1016/j.actamat.2025.121229","DOIUrl":"10.1016/j.actamat.2025.121229","url":null,"abstract":"<div><div>Most refractory high-entropy alloys (RHEAs) are susceptible to brittle fracture when subjected to tensile loading. The TiZrHfNb RHEA and its derivative possess good tensile ductility, but still encounter issues with low yield strength. In this study, we propose an Oxygen-Nitrogen Synergistic Effect (ONSE) for reinforcing the TiZrHfNb RHEA. Oxygen atoms create local chemical order (LCO), seeding more dislocation nucleation sites, promoting dislocation multiplication and ensuring uniform deformation. Nitrogen atoms induce lattice distortion, hinder dislocation motion, and generate a significant solid solution strengthening effect. The introduction of ONSE results in high-density mobile dislocations distributed throughout the alloy, as opposed to the conventional belief that dislocations are limited to narrow slip bands by LCOs. The model alloy (TiZrHfNb)₉₈N_1.5O_0.5 (at. %) designed by ONSE showed a significantly improved yield strength of 1412.9 ± 13.5 MPa, representing a 92 % enhancement compared to the TiZrHfNb RHEA, while maintaining a fracture elongation of 10 %. Our strengthening approach provides a new option for improving the strength of other body-centered-cubic (BCC) RHEAs.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121229"},"PeriodicalIF":8.3,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144237442","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":"Superior irradiation resistance via nanocrystalline grains of 316L austenitic stainless steel","authors":"Aoxiang Gong ,&nbsp;Chaojun Luo ,&nbsp;Chi Xu ,&nbsp;Zhenfeng Tong","doi":"10.1016/j.actamat.2025.121228","DOIUrl":"10.1016/j.actamat.2025.121228","url":null,"abstract":"<div><div>The microstructural changes in nanocrystalline (NC) 316L and cold worked (CW) 316L austenitic stainless steels were investigated under irradiation. The nanocrystalline grain structure remained stable under all irradiation conditions of 0.3, 1.14, and 157 dpa and temperatures up to 300 °C due to the significantly higher grain boundary density compared to coarse grains. This character enables the superior radiation resistance of the material. The grain boundary structures act effectively as defect sinks, resulting in fewer dislocation loops and smaller/fewer bubbles, with a better performance against irradiation swelling and radiation induced segregation. Meanwhile, bubble depleted zones were observed around the GBs, due to the sink effect. Their width was found to decrease with the increase of the angle of the grain boundaries in the NC sample under He irradiation, which is closely related to the stress-strain and the dislocation density at the grain boundaries.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121228"},"PeriodicalIF":8.3,"publicationDate":"2025-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144237191","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":"Reversible detwinning and texture evolution in a nanocrystalline NiTi alloy during deformation","authors":"Yuxuan Chen ,&nbsp;Xiaobin Shi ,&nbsp;Junsong Zhang ,&nbsp;Yang Ren ,&nbsp;Shan Huang ,&nbsp;Zepei Yao ,&nbsp;Shuzhi Zhang ,&nbsp;Xinyu Zhang ,&nbsp;Riping Liu ,&nbsp;Yinong Liu","doi":"10.1016/j.actamat.2025.121224","DOIUrl":"10.1016/j.actamat.2025.121224","url":null,"abstract":"<div><div>This study investigated the phenomenon of crystallographic and mechanical reversibility of detwinning of martensite in a nanocrystalline Ni_50.8Ti_49.2 alloy wire by means of <em>in-situ</em> high energy X-ray diffraction and phenomenological theoretical analyses. By studying the formation and evolution of crystallographic textures of the R phase and the B19′ phase during pseudoelastic deformation, it was found that for the R phase the reorientation of lattice correspondence variant pairs (CVPs) and detwinning between the variants within a CVP occur concurrently upon loading, forming a single variant R phase prior to the stress-induced R → B19′ martensitic transformation. This texture evolution of the R phase was reversible upon unloading, indicating retwining of the R phase. The stress-induced B19′ phase formed exhibited two textures, signaling the formation of one internally twined CVP. Detwinning of the B19′ variants within the CVP occurred upon further deformation in conjunction with elastic and plastic deformation. The detwinning of the B19′ martensite was also spontaneously reversible upon unloading, in contrast with the common perception that variant reorientation and detwinning are thermodynamically irreversible. This is explained on the basis of local lattice distortions and internal elastic stresses generated as a result of, or as a penalty for, the violation of habit plane requirement caused by variant detwinning within a CVP. These internal lattice stresses serve as the driving force for self-recovery, or retwinning, of the martensite upon unloading. These findings provide a guidance to the interpretation of the mechanical behavior and design of NiTi alloys of ultra-low elastic moduli.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121224"},"PeriodicalIF":8.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144237230","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":"A combined DFT and MD study on interface stability in ferrite–cementite systems","authors":"Pablo Canca ,&nbsp;Chu-Chun Fu ,&nbsp;Christophe J. Ortiz ,&nbsp;Blanca Biel","doi":"10.1016/j.actamat.2025.121157","DOIUrl":"10.1016/j.actamat.2025.121157","url":null,"abstract":"<div><div>Understanding the atomic structure and energetic stability of ferrite–cementite interfaces is essential for optimising the mechanical performance of steels, especially under extreme conditions such as those encountered in nuclear fusion environments. In this work, we combine Classical Molecular Dynamics (MD) and Density Functional Theory (DFT) to systematically investigate the stability of ferrite–cementite interfaces within the Bagaryatskii Orientation Relationship. Three interface orientations and several cementite terminations are considered to identify the most stable configurations.</div><div>MD simulations reveal that the <span><math><mrow><msub><mrow><mrow><mo>(</mo><mn>010</mn><mo>)</mo></mrow></mrow><mrow><mi>θ</mi></mrow></msub><mrow><mo>|</mo><mo>|</mo></mrow><msub><mrow><mrow><mo>(</mo><mn>11</mn><mover><mrow><mn>2</mn></mrow><mrow><mo>̄</mo></mrow></mover><mo>)</mo></mrow></mrow><mrow><mi>α</mi></mrow></msub></mrow></math></span> and <span><math><mrow><msub><mrow><mrow><mo>(</mo><mn>001</mn><mo>)</mo></mrow></mrow><mrow><mi>θ</mi></mrow></msub><mrow><mo>|</mo><mo>|</mo></mrow><msub><mrow><mrow><mo>(</mo><mn>1</mn><mover><mrow><mn>1</mn></mrow><mrow><mo>̄</mo></mrow></mover><mn>0</mn><mo>)</mo></mrow></mrow><mrow><mi>α</mi></mrow></msub></mrow></math></span> orientations are energetically favourable for selected terminations, and these predictions are validated and refined by subsequent DFT calculations. A key result of our study is the destabilising effect of interfacial carbon atoms, which increase the interface energy and decrease the Griffith energy, indicating a reduced resistance to fracture. This finding contrasts with earlier reports suggesting a stabilising role for carbon.</div><div>Our analysis of the electronic structure shows that Fe–C bonding at the interface perturbs the metallic environment of interfacial Fe atoms. This bonding response explains the observed variations in magnetic moment and helps rationalise the trends in interface energy. We also establish correlations between interface energy, magnetic perturbation, and a bond-based descriptor quantifying new and broken bonds. These insights provide a physically grounded, predictive framework for the design and optimisation of ferrite–cementite interfaces in advanced steels.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121157"},"PeriodicalIF":8.3,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144228766","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":"Double-tough ceramics: Optimization-supported multiscale computational design","authors":"Jian Zhang ,&nbsp;Francesco Aiello ,&nbsp;Mauro Salazar ,&nbsp;Diletta Giuntini","doi":"10.1016/j.actamat.2025.121162","DOIUrl":"10.1016/j.actamat.2025.121162","url":null,"abstract":"<div><div>To overcome the brittleness limitation of ceramics, various toughening mechanisms have been proposed. Some of the most remarkable, especially for oxides, include the tetragonal-to-monoclinic phase transformation leading to crack shielding in zirconia, and bioinspired brick-and-mortar microstructures fostering crack deflection. It has, however, proven challenging to incorporate both these mechanisms into a single all-ceramic material. In this work, we propose a computational methodology for the design of a material that combines these two toughening strategies, using a multiscale modeling approach that captures both their individual contributions and the overall fracture performance. This is achieved by developing an all-ceramic composite with a brick-and-mortar microstructure, in which the nanocrystalline mortar is transformation-toughened. Key factors influencing phase transformation, such as grain boundary properties, grain orientations, and kinetic coefficients, are analyzed, and the resulting transformation stress–strain behavior is incorporated into the microscale mortar constitutive model. We demonstrate that the synergistic effect of the two toughening mechanisms is achievable, and that it is an extremely effective strategy to boost fracture performance. The influence of brick size, mortar thickness, and properties of the constituent materials is then systematically investigated. Finally, a gradient-free optimization algorithm is employed to identify optimal geometric and material parameters, revealing that longer, thinner bricks with minimal mortar thickness provide the best fracture resistance. Optimal combinations of material properties are identified for given brick sizes and mortar thicknesses.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121162"},"PeriodicalIF":8.3,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144228764","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":"MX precipitate behavior in an irradiated advanced Fe-9Cr steel: Self-ion irradiation effects on phase stability","authors":"T.M. Kelsy Green ,&nbsp;Tim Gräning ,&nbsp;Weicheng Zhong ,&nbsp;Ying Yang ,&nbsp;Kevin G. Field","doi":"10.1016/j.actamat.2025.121203","DOIUrl":"10.1016/j.actamat.2025.121203","url":null,"abstract":"<div><div>In an effort to optimize Fe-9Cr reduced activation ferritic/martensitic (RAFM) steels and to inform the design and operation of fusion reactors, this work represents the first in a series of cohesive studies dedicated to the evolution of MX-TiC precipitates under accelerated single and dual ion irradiations. This study investigates CNA9, a simplified Fe-9Cr RAFM steel featuring initial MX-TiC precipitate densities of (2.3±0.3)×10²¹ m⁻³. This material was subjected to single self-ion irradiation at damage levels ranging from 1 to 100 displacements per atom (dpa) over a temperature range of 300 to 600°C, with a nominal dose rate of 7×10⁻⁴ dpa/s. Irradiation-induced coarsening was observed, as evidenced by statistically significant increases in mean diameter sizes, at 15 dpa at both 500°C and 600°C, whereas no coarsening was noted at 300°C or 400°C. Complete dissolution of precipitates occurred at damage levels of 50 and 100 dpa across the two temperatures tested (300°C and 500°C) while no significant changes were observed at any doses below 15 dpa at 500°C. Experimentally parameterized recoil resolution modeling suggests that the observed radiation stability of MX-TiC precipitates is intricately linked to diffusional changes of solutes resulting from the co-evolution of microstructural features within the experiments. The findings align with current theoretical perspectives on radiation-induced precipitate stability in complex alloys.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121203"},"PeriodicalIF":8.3,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144228765","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":"Enhancing Coercivity and Thermal Stability in High-Remanence Nd-Fe-B Magnets via TbF3 Grain Boundary Diffusion","authors":"Shilin Li, Youhong Peng, Yaodong Wu, Yuqing Xing, Yu Zhang, Tao Liu, Sitian Cai, Qiong Wu, Ming Yue, Haifeng Du, Jin Tang","doi":"10.1016/j.actamat.2025.121176","DOIUrl":"https://doi.org/10.1016/j.actamat.2025.121176","url":null,"abstract":"Applications in the field of magnetic motors, separators, etc., necessitate permanent magnets exhibiting a synergy between coercivity and remanence. However, sintered Nd-Fe-B magnets with high remanence feature relatively large grains leading to a decrease in coercivity. In this study, we investigate the impact of the TbF₃ grain boundary diffusion process (GBDP) on sintered Nd-Fe-B magnets possessing a high remanence of 14.92 kGs but a low coercivity of 9.92 kOe. Through TbF₃ diffusion, we observe a substantial increase in room-temperature coercivity by 84%, reaching 18.25 kOe, accompanied by a relatively minor reduction in remanence (<em>∼</em> 0.31 kGs). Notably, the diffused magnets maintain a coercivity of 5.3 kOe at elevated temperatures (150°C), demonstrating effective improvement in thermal stability. The modifications in core-shell structures and grain boundaries due to the GBDP are systematically characterized using an electron probe micro-analyzer and transmission electron microscopy. Furthermore, micromagnetic simulations are employed to discuss the enhancement in coercivity attributed to shell thickness. Our findings, which achieve a synergy between coercivity and remanence in Nd-Fe-B sintered magnets, hold the potential to advance applications of permanent magnets.","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"176 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144219372","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":"Unique temperature-dependence of polarization switching paths in ferroelectric BaTiO3: A molecular dynamics simulation study","authors":"Hikaru Azuma ,&nbsp;Tomohiro Ogawa ,&nbsp;Shuji Ogata ,&nbsp;Ryo Kobayashi ,&nbsp;Masayuki Uranagase ,&nbsp;Takahiro Tsuzuki ,&nbsp;Frank Wendler","doi":"10.1016/j.actamat.2025.121216","DOIUrl":"10.1016/j.actamat.2025.121216","url":null,"abstract":"<div><div>Polarization switching in ferroelectrics under an external electric field is crucial for their application in memory devices and actuators. Experimental research has identified two distinct polarization switching processes in tetragonal BaTiO₃ (BT) when applying an external electric field in the direction opposite to the polarization: (i) direct inversion of polarization and (ii) two-step inversion composed of two-times 90° rotation of polarization. In this study, we performed molecular dynamics simulations using accurate shell-model interatomic potential to unravel the mechanisms distinguishing these two processes. We established updated shell-model parameters by fitting them to various physical properties, including phonon dispersions obtained from density-functional theory utilizing an appropriate combination of meta-generalized gradient approximation exchange-correlation functional and dispersion force correction. When applying an external electric field in the <span><math><mrow><mo>−</mo><mi>c</mi></mrow></math></span>-direction to a tetragonal BT crystal polarized along <span><math><mi>c</mi></math></span>-direction, the polarization switches through two-times 90° rotation at low temperatures and through formation of a polarization-inverted nucleus at high temperatures. The coercive field <span><math><msubsup><mi>E</mi><mrow><mi>c</mi></mrow><mo>∥</mo></msubsup></math></span> along <span><math><mrow><mo>−</mo><mi>c</mi></mrow></math></span>-direction increases with temperature at low temperatures, while decreases at high temperatures. In contrast, when the external electric field is applied along <span><math><mi>b</mi></math></span>-direction, the coercive field <span><math><msubsup><mi>E</mi><mrow><mi>c</mi></mrow><mi>⊥</mi></msubsup></math></span> is smaller than <span><math><msubsup><mi>E</mi><mrow><mi>c</mi></mrow><mo>∥</mo></msubsup></math></span> and increases monotonically with temperature. The polarization rotated in <span><math><mi>b</mi></math></span>-direction without nucleation along with deformation through orthorhombic structure. Unique temperature dependencies of <span><math><msubsup><mi>E</mi><mrow><mi>c</mi></mrow><mo>∥</mo></msubsup></math></span> and <span><math><msubsup><mi>E</mi><mrow><mi>c</mi></mrow><mi>⊥</mi></msubsup></math></span> are attributed to the pronounced fluctuations in local polarizations perpendicular to the system polarization and the proximity of temperature to the orthorhombic-tetragonal transition point. Present findings offer essential information in designing BT-based ferroelectrics with doping.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"296 ","pages":"Article 121216"},"PeriodicalIF":8.3,"publicationDate":"2025-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144219371","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}