Acta Materialia最新文献_第4页

Confined necking and improved tensile ductility in heterostructured bi-metallic steels made by additive manufacturing 增材制造双金属异质结构钢的限制颈缩和提高拉伸延展性

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-20 DOI: 10.1016/j.actamat.2026.121952

Xiao Shang , Chenwei Shao , Soumya S. Dash , Lulu Guo , Joseph Agyapong , Lizhong Lang , Alec Chen , Sang Bum Yi , Tianyi Lyu , Hao Chen , Solomon Boakye-Yiadom , Yu Zou

Achieving high tensile ductility is critical for structural materials, ensuring reliable load-bearing capability and adequate formability.. Steels, the most widely used structural metals, show a wide range of elongation to failure, from a few percent to a few tens of percent. Recently, heterostructured materials (HMs) have been reported to exhibit superior tensile properties that surpass those of their homogeneous counterparts. Classical HMs with heterogeneity in the length scale less than a few hundred nanometres attribute their enhanced mechanical performance mainly to the hetero-deformation induced (HDI) hardening. However, the underlying mechanisms for HMs with mesoscale heterogeneities, i.e., in the length scale of a few hundred micrometers, are overlooked. Recent advances in additive manufacturing (AM) have provided opportunities to fabricate HMs over the mesoscale range with structural complexity. In this work, we employ the AM method to fabricate a new type of mesoscale HM: bi-metallic heterostructured steels (HSs), consisting of 316L and PH17–4 stainless steels that possess distinct tensile strength and ductility. By tuning the ratios and fractions of 316L/PH17–4, we achieve 27.3%, 11.5%, and 1.8% improvements in the tensile ductility, ultimate tensile strength, and yield strength over 316L, respectively. Such enhanced tensile properties are mainly attributed to (i) confined-necking co-deformation, where the necking of PH17–4 is confined and delayed by 316L, offering more work hardening to the whole sample, (ii) switching between necking-induced and shear-induced failure modes, and (iii) the HDI hardening effect. This study paves the way for understanding and designing bi-metallic HSs with improved tensile properties using AM methods.

在结构材料中实现高拉伸延展性是至关重要的，因为它支持可靠的承载性能和良好的成形性。钢是应用最广泛的结构金属，其延伸率到失效的范围很广，从几个百分点到几十个百分点不等。最近，异质结构材料（HMs）表现出优于同类材料的优异拉伸性能。非均质性小于几百纳米的经典材料，其力学性能的增强主要归因于异质变形诱导（HDI）硬化。然而，具有中尺度异质性的HMs的潜在机制，即几百微米的长度尺度，被忽视了。增材制造（AM）的最新进展为在结构复杂的中尺度范围内制造HMs提供了机会。在这项工作中，我们采用增材制造方法制造了一种中尺度HM：双金属异质结构钢（HSs），由316L和PH17-4不锈钢组成，具有不同的拉伸强度和延展性。通过调整316L/PH17-4的比例和分数，我们在拉伸延展性、极限拉伸强度和屈服强度方面分别比316L提高了27.3%、11.5%和1.8%。这种增强的拉伸性能主要归因于(i)局限颈缩共变形，其中PH17-4的颈缩受到316L的限制和延迟，为整个样品提供了更多的加工硬化，（ii）颈缩诱导和剪切诱导破坏模式之间的切换，以及（iii） HDI硬化效应。本研究为利用增材制造方法理解和设计具有改进拉伸性能的双金属高速钢铺平了道路。

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引用次数: 0

A dual-phase strain-transformable zirconium alloy with exceptional yield strength (1.2 GPa) and low elastic modulus (70 GPa) via TWIP and phase reversion 通过TWIP和相还原制备了一种具有优异屈服强度（1.2 GPa）和低弹性模量（70 GPa）的双相应变变形锆合金

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-25 DOI: 10.1016/j.actamat.2026.121966

Junhui Tang , Nicolas Jobit , Agata Sotniczuk , Witold Chromiński , Denis Laillé , Daniel Galy , Philippe Vermaut , Phillippe Castany , Thierry Gloriant , Ju Li , Frédéric Prima , Fan Sun

The present study focuses on the development of a novel Zr-12Nb-3Sn alloy displaying a body-centered tetragonal (BCT) / β dual-phase microstructure and engineered to achieve a superior combination of high strength and low elastic modulus. The BCT phase is shown to play a critical role in enhancing strength without increasing elastic modulus. Comprehensive analyses using in situ straining electron backscatter diffraction (EBSD) experiment and transmission electron microscopy (TEM) were conducted to characterize the microstructure of the BCT phase and the associated deformation mechanisms, including dislocation slip, stress-induced reversion from BCT to β transformation, and mechanical twinning. The present findings reveal that the BCT phase and mechanical twinning both contribute to material strengthening, whereas the stress-induced reversion of the BCT phase to β acts as a mechanism for stress relaxation. As a result, the alloy demonstrates exceptional mechanical performance, achieving a yield strength exceeding 1200 MPa, an elastic modulus of approximately 70 GPa, and an elongation of ∼13%.

本研究的重点是开发一种具有体心四方(BCT) / β双相组织的新型Zr-12Nb-3Sn合金，并通过工程设计实现了高强度和低弹性模量的卓越结合。BCT阶段在不增加弹性模量的情况下对增强强度起关键作用。利用原位应变电子背散射衍射（EBSD）实验和透射电子显微镜（TEM）综合分析了BCT相的微观结构和相关的变形机制，包括位错滑移、应力诱导的BCT向β转变的逆转和机械孪晶。目前的研究结果表明，BCT相和机械孪晶都有助于材料的强化，而应力诱导的BCT相向β的逆转是应力松弛的机制。因此，该合金表现出优异的机械性能，屈服强度超过1200 MPa，弹性模量约为70 GPa，伸长率约为13%。

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引用次数: 0

Fe2CrSi thin film as magnetocaloric refrigerant to liquefy/solidify high-boiling-point harmful organic substances and its associated critical phenomena Fe2CrSi薄膜作为磁热制冷剂液化/固化高沸点有害有机物及其相关临界现象

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-24 DOI: 10.1016/j.actamat.2026.121964

Sourav Mandal, Tapan Kumar Nath

Harmful organic chemical substances require liquefaction or solidification for safe handling, but their high boiling points present significant challenges. Liquefaction of H₂ gas using the magnetocaloric response (MCR) near its boiling point has been proposed, highlighting the need for effective magnetic refrigerants at similar temperatures. This study introduces a potential refrigerant: a 52.4 nm thin film of half-metallic ferromagnetic (HMF) Full-Heusler alloy Fe₂CrSi, deposited on a single-crystalline p-type Si <100> wafer via electron-beam physical vapor deposition (EBPVD), aimed at enabling the safe handling of such substances. The thin film exhibits a continuous ‘ferromagnetic-to-paramagnetic phase transition’ above the ‘Curie temperature’ (

θ_{C W}

= + 607.828 K), a ‘second-order magnetic phase transition’ (SOMPT). This HMF film possesses adequate significance for refrigeration and spintronics applications for high ‘relative cooling power’ (‘RCP’) of 380.85 mJ.cm^-3 (equivalent to 57.01 J.Kg^-1) at a 20 kOe field change; large ‘operating temperature range’ of 78.18 K; low constituent cost; non-toxic elements; zero thermal hysteresis; and high Curie temperature, respectively. The ‘spontaneous magnetization value close to 0 K’, M_s(0), is determined to be 56.868 emu/g (∼ 1.953 µ_B/f.u.) by extrapolating the Arrott plot to the H/M = 0 axis. It is consistent with the ‘Slater-Pauling (S-P) rule’. Additionally, using Critical Isotherms (CI), ‘Rusbrooke equality’ and ‘Widom-scaling relation’, the most feasible values of its ‘critical exponents’ (α ≈ -1.144, β ≈ 0.735, γ ≈ 1.674 and δ ≈ 3.278), across the film’s SOMPT, are predicted.

有害的有机化学物质需要液化或固化才能安全处理，但它们的高沸点带来了重大挑战。利用沸点附近的磁热响应（MCR）液化h2气体已经被提出，强调需要在相似温度下有效的磁性制冷剂。本研究介绍了一种潜在的制冷剂：通过电子束物理气相沉积（EBPVD）将半金属铁磁（HMF） Full-Heusler合金Fe2CrSi的52.4 nm薄膜沉积在单晶p型Si <；100>；晶圆上，旨在实现此类物质的安全处理。在居里温度（θCW = + 607.828 K）以上，薄膜表现出连续的“铁磁-顺磁相变”，即“二阶磁相变”（SOMPT）。这种HMF薄膜对于380.85 mJ的高“相对冷却功率”（RCP）的制冷和自旋电子学应用具有足够的意义。cm-3（相当于57.01 j.k kg -1）在20koe场变化；78.18 K的大工作温度范围；组成成本低；无毒的元素;零热滞后；和高居里温度。通过向H/M = 0轴外推Arrott图，确定接近0 K的自发磁化值Ms(0)为56.868 emu/g（~ 1.953µB/f.u.）。这符合“Slater-Pauling （S-P）规则”。此外，利用临界等温线（CI）、“Rusbrooke等式”和“widom尺度关系”，预测了整个电影SOMPT的“临界指数”（α≈-1.144,β≈0.735,γ≈1.674和δ≈3.278）的最可行值。

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引用次数: 0

Reaction kinetics and phase evolution of nanoporous TaC from metallic precursors 金属前驱体制备纳米多孔TaC的反应动力学及相演化

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-02-02 DOI: 10.1016/j.actamat.2026.121980

Catherine Ott , Adam Peters , Ian McCue

Ultra-high temperature ceramics (UHTCs) are promising materials for use in next-generation aerospace structures but have processing challenges, particularly with respect to densification. Here, a nano-sized UHTC powder precursor was synthesized via atmospheric pressure gas-phase carburization of nanoporous tantalum to the ultra-high-temperature ceramic, TaC, at unconventionally low temperatures (700–900 °C). First, a 1-D moving interface model was constructed to predict carburization depth and compare data from the present work to that in the literature, and the model was validated for finite geometries (i.e., powders). Then, the kinetic properties of Ta conversion in a carburizing environment were examined over a range of temperatures to determine rate-limiting behavior and activation energy for the process. It was found that the apparent activation energy for carburization was initially low, and conversion proceeded much faster than predicted, suggesting accelerated carbon diffusion pathways. Detailed microstructural analysis was carried out on in-house atomized powders, which did not show evidence of grain boundary diffusion. Instead, it revealed that the effects of residual strain and defects from processing may play a significant role in the carburization rates of tantalum.

超高温陶瓷（UHTCs）是下一代航空航天结构中很有前途的材料，但在加工方面存在挑战，特别是在致密化方面。在这里，通过常压气相渗碳纳米多孔钽到超高温陶瓷TaC，在非常规低温（700-900℃）下合成了纳米尺寸的UHTC粉末前驱体。首先，构建了一个一维移动界面模型来预测渗碳深度，并将本工作的数据与文献中的数据进行比较，并对有限几何形状（即粉末）的模型进行了验证。然后，在一定温度范围内测试了渗碳环境中Ta转化的动力学性质，以确定该过程的限速行为和活化能。结果表明，渗碳的表观活化能较低，渗碳过程比预测的要快得多，表明碳的扩散途径加快。对内部雾化粉末进行了详细的显微组织分析，没有显示晶界扩散的证据。结果表明，残余应变和加工缺陷的影响可能对钽的渗碳速率起重要作用。

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引用次数: 0

DFT-assisting experimental insights into the thermally grown oxide of thermal barrier coatings with Cr2AlC as the bond coat 以Cr2AlC为粘结层的热障涂层的热生长氧化物的dft辅助实验见解

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-28 DOI: 10.1016/j.actamat.2026.121974

Jinze Zhang , Chunzhu Jiang , Xiaodong He , Chuchu Yang , Zhiyao Lu , Kebin Qin , Hang Yin , Yongting Zheng , Guangping Song , Hongming Zhang , Yuelei Bai

Because of the high oxidation resistance and appropriate coefficient of thermal expansion (CTE), Cr₂AlC has emerged as a promising bond coat (BC) for thermal barrier coatings (TBCs), but the insufficient understanding for its thermally grown oxide (TGO) and underlying mechanisms potentially hinders its practical applications. Herein, the isothermal oxidation behavior and associated TGO of TBCs with Cr₂AlC as the BC was experimentally examined at 900-1150°C with the mechanism revealed by density functional theory (DFT). Interestingly, facilitated by enhanced Al diffusivity and reactivity, a dense, continuous and nanocrystalline α-Al₂O₃-dominated TGO layer formed on top of the Cr₂AlC BC, accompanied by its decomposition into Cr₃C₂. Besides, the favorable CTE match among Cr₂AlC, Cr₃C₂, Al₂O₃ and 8YSZ ensured the TGO integrity, while it exhibited cubic oxidation kinetics, with consistently reduced thickness compared to MCrAlY. DFT simulations corroborated these experimental trends and revealed the intrinsic mechanisms: lower oxygen adsorption energy (ΔE_ads) on Cr₂AlC (-5.22 to -4.33 eV) versus MCrAlY (-0.94 eV). This was attributed to high oxygen affinity of Al in Cr₂AlC and inherent Al-O reactivity, promoting oxygen capture and initial nucleation of protective oxides. Moreover, cramped Cr-C interlayers were found to effectively inhibit the oxygen penetration through the (0001) surface, providing an additional mechanism for enhanced oxidation resistance of Cr₂AlC. These findings provide fundamental insights into oxidation mechanisms of the Cr₂AlC BC and offer a guidance to optimize its oxidation resistance for high-temperature applications.

Cr2AlC具有较高的抗氧化性和适当的热膨胀系数（CTE），是热障涂层（tbc）中很有前途的粘结层，但对其热生长氧化物（TGO）及其机理的认识不足，可能阻碍其实际应用。本文利用密度泛函理论（DFT）分析了tbc在900 ~ 1150℃的等温氧化行为和与Cr2AlC作为BC相关的TGO。有趣的是，在Al扩散率和反应性增强的促进下，Cr2AlC BC表面形成致密、连续、以α- al2o3为主的纳米晶TGO层，并伴随其分解成Cr3C2。此外，Cr2AlC、Cr3C2、Al2O3和8YSZ之间良好的CTE匹配保证了TGO的完整性，同时表现出立方氧化动力学，与MCrAlY相比厚度持续降低。DFT模拟证实了这些实验趋势，并揭示了内在机制：Cr2AlC（-5.22至-4.33 eV）比MCrAlY （-0.94 eV）更低的氧吸附能（ΔEads）。这是由于Cr2AlC中Al的高氧亲和性和固有的Al- o反应性，促进氧捕获和保护性氧化物的初始成核。此外，狭窄的Cr-C中间层可以有效地抑制氧通过（0001）表面的渗透，为增强Cr2AlC的抗氧化性提供了额外的机制。这些发现为深入了解Cr2AlC BC的氧化机制提供了基础，并为优化其高温应用的抗氧化性提供了指导。

{"title":"DFT-assisting experimental insights into the thermally grown oxide of thermal barrier coatings with Cr2AlC as the bond coat","authors":"Jinze Zhang , Chunzhu Jiang , Xiaodong He , Chuchu Yang , Zhiyao Lu , Kebin Qin , Hang Yin , Yongting Zheng , Guangping Song , Hongming Zhang , Yuelei Bai","doi":"10.1016/j.actamat.2026.121974","DOIUrl":"10.1016/j.actamat.2026.121974","url":null,"abstract":"<div><div>Because of the high oxidation resistance and appropriate coefficient of thermal expansion (CTE), Cr<sub>2</sub>AlC has emerged as a promising bond coat (BC) for thermal barrier coatings (TBCs), but the insufficient understanding for its thermally grown oxide (TGO) and underlying mechanisms potentially hinders its practical applications. Herein, the isothermal oxidation behavior and associated TGO of TBCs with Cr<sub>2</sub>AlC as the BC was experimentally examined at 900-1150°C with the mechanism revealed by density functional theory (DFT). Interestingly, facilitated by enhanced Al diffusivity and reactivity, a dense, continuous and nanocrystalline α-Al<sub>2</sub>O<sub>3</sub>-dominated TGO layer formed on top of the Cr<sub>2</sub>AlC BC, accompanied by its decomposition into Cr<sub>3</sub>C<sub>2</sub>. Besides, the favorable CTE match among Cr<sub>2</sub>AlC, Cr<sub>3</sub>C<sub>2</sub>, Al<sub>2</sub>O<sub>3</sub> and 8YSZ ensured the TGO integrity, while it exhibited cubic oxidation kinetics, with consistently reduced thickness compared to MCrAlY. DFT simulations corroborated these experimental trends and revealed the intrinsic mechanisms: lower oxygen adsorption energy (Δ<em>E</em><sub>ads</sub>) on Cr<sub>2</sub>AlC (-5.22 to -4.33 eV) versus MCrAlY (-0.94 eV). This was attributed to high oxygen affinity of Al in Cr<sub>2</sub>AlC and inherent Al-O reactivity, promoting oxygen capture and initial nucleation of protective oxides. Moreover, cramped Cr-C interlayers were found to effectively inhibit the oxygen penetration through the (0001) surface, providing an additional mechanism for enhanced oxidation resistance of Cr<sub>2</sub>AlC. These findings provide fundamental insights into oxidation mechanisms of the Cr<sub>2</sub>AlC BC and offer a guidance to optimize its oxidation resistance for high-temperature applications.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"307 ","pages":"Article 121974"},"PeriodicalIF":9.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146072317","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}

引用次数: 0

Phase transition of NaNbO3-based antiferroelectric ceramics: Doping research based on DFT calculation 纳米硼基反铁电陶瓷的相变：基于DFT计算的掺杂研究

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-26 DOI: 10.1016/j.actamat.2026.121967

Yile Yang , Jing Shang , Jinbo Zhang , Pengfan Lv , Jiachen Li , Yiting Hui , Lei Zhang , Min Chen , Shaobin Zhang , Man Yu , Yongping Pu

The practical application in electronic devices of NaNbO₃ (NN)-based ceramics by utilizing the antiferroelectric (AFE) behavior is highly limited by its phase instability and insufficient breakdown strength. Traditional approaches rely heavily on extensive experimental validation, and the fundamental mechanisms remain poorly understood. To address these challenges, density functional theory (DFT) calculations were performed in the present study to predict the effects of Sm doping at the A-site of NN on structural and energy variation. The calculated results indicate that Sm doping stabilizes the AFE-R phase by lowering its formation energy relative to the FE-Q and AFE-P phases, revealing a clear preference toward the AFE-R configuration. Guided by theoretical predictions, Na_1-_xSm_xNbO_3+δ ceramics were designed and synthesized in this study to verify the calculated results. Experimental results indicate that substitutional doping at the A-site could effectively help to stabilize the AFE-R phase. With the increasing doping concentration, the substitution effect of Sm³⁺ becomes more pronounced, leading to an enhanced relaxor behavior in the AFE-R phase and resulting in a slim P-E loop, consistent with the larger calculated ∆E values. Additionally, the SmNbO₄ phase with low dielectric constant and high breakdown strength gradually precipitates at the grain boundaries, contributing to improved electrical performance of the ceramics. The potential mechanism of the improved breakdown strength and the energy storage performance were further revealed by electron paramagnetic resonance (EPR) and piezoresponse force microscopy (PFM) measurements. These results provide theoretical insights and experimental evidence for the development of lead-free ceramics with high-performance energy storage capabilities.

利用反铁电（AFE）行为制备的纳米bo3 （NN）基陶瓷在电子器件中的实际应用受到相不稳定性和击穿强度不足的严重限制。传统的方法严重依赖于广泛的实验验证，基本机制仍然知之甚少。为了解决这些挑战，本研究采用密度泛函理论（DFT）计算来预测Sm在神经网络a位掺杂对结构和能量变化的影响。计算结果表明，相对于FE-Q和fe - p相，Sm掺杂降低了fe - r相的形成能，从而稳定了fe - r相，显示出明显的偏向于fe - r的构型。在理论预测的指导下，本研究设计并合成了Na1-xSmxNbO3+δ陶瓷，以验证计算结果。实验结果表明，a位的取代掺杂可以有效地稳定fe - r相。随着掺杂浓度的增加，Sm3+的取代效应更加明显，导致af - r相弛豫行为增强，P-E环变细，与较大的计算∆E值一致。此外，具有低介电常数和高击穿强度的SmNbO4相在晶界处逐渐析出，有助于提高陶瓷的电性能。通过电子顺磁共振（EPR）和压电响应力显微镜（PFM）的测量进一步揭示了提高击穿强度和储能性能的潜在机制。这些结果为开发具有高性能储能能力的无铅陶瓷提供了理论见解和实验证据。

{"title":"Phase transition of NaNbO3-based antiferroelectric ceramics: Doping research based on DFT calculation","authors":"Yile Yang , Jing Shang , Jinbo Zhang , Pengfan Lv , Jiachen Li , Yiting Hui , Lei Zhang , Min Chen , Shaobin Zhang , Man Yu , Yongping Pu","doi":"10.1016/j.actamat.2026.121967","DOIUrl":"10.1016/j.actamat.2026.121967","url":null,"abstract":"<div><div>The practical application in electronic devices of NaNbO<sub>3</sub> (NN)-based ceramics by utilizing the antiferroelectric (AFE) behavior is highly limited by its phase instability and insufficient breakdown strength. Traditional approaches rely heavily on extensive experimental validation, and the fundamental mechanisms remain poorly understood. To address these challenges, density functional theory (DFT) calculations were performed in the present study to predict the effects of Sm doping at the A-site of NN on structural and energy variation. The calculated results indicate that Sm doping stabilizes the AFE-R phase by lowering its formation energy relative to the FE-Q and AFE-P phases, revealing a clear preference toward the AFE-R configuration. Guided by theoretical predictions, Na<sub>1-</sub><em><sub>x</sub></em>Sm<em><sub>x</sub></em>NbO<sub>3+δ</sub> ceramics were designed and synthesized in this study to verify the calculated results. Experimental results indicate that substitutional doping at the A-site could effectively help to stabilize the AFE-R phase. With the increasing doping concentration, the substitution effect of Sm<sup>3+</sup> becomes more pronounced, leading to an enhanced relaxor behavior in the AFE-R phase and resulting in a slim <em>P</em>-<em>E</em> loop, consistent with the larger calculated ∆<em>E</em> values. Additionally, the SmNbO<sub>4</sub> phase with low dielectric constant and high breakdown strength gradually precipitates at the grain boundaries, contributing to improved electrical performance of the ceramics. The potential mechanism of the improved breakdown strength and the energy storage performance were further revealed by electron paramagnetic resonance (EPR) and piezoresponse force microscopy (PFM) measurements. These results provide theoretical insights and experimental evidence for the development of lead-free ceramics with high-performance energy storage capabilities.</div></div>","PeriodicalId":238,"journal":{"name":"Acta Materialia","volume":"307 ","pages":"Article 121967"},"PeriodicalIF":9.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146047857","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}

引用次数: 0

CuCoCrRuMo HEA achieving Cl− repulsion and Mg resource recovery in industrial-current-density seawater electrolysis cuccrrumo HEA在工业电流密度海水电解中实现Cl -排斥和镁资源回收

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-28 DOI: 10.1016/j.actamat.2026.121971

Hao He , Zhiyuan Chen , Wansen Ma , Qigang Chen , Qian Li , Xuewei Lv , Jie Dang

Seawater-electrolysis is a promising green method for hydrogen production, but the high corrosiveness of seawater and magnesium hydroxide precipitation during electrolysis quickly deactivate the cathode. Therefore, developing efficient and low-cost electrocatalysts remains a key challenge in this field. Herein, we develop a high-entropy alloy (CuCoCrRuMo HEA) catalyst for seawater electrolysis hydrogen production, simultaneously achieving the recovery of magnesium resources from seawater. The formation of MoO₄²⁻ during the OER process effectively repels Cl⁻, mitigating catalyst corrosion. Additionally, the Cr₂O₃ enhances the corrosion resistance of the catalyst. The alloy also facilitates the deposition and recovery of Mg(OH)₂ by repelling Mg²⁺, enabling efficient utilization of seawater resources. In 1 M KOH, the CuCoCrRuMo HEA exhibits overpotentials of 402 mV for HER and 450 mV for OER at the current density of 1000 mA cm⁻². In 1 M KOH + 0.5 M NaCl (simulated seawater), the overpotentials decrease to 368 mV for HER and 430 mV for OER. Moreover, sustaining HER and OER performance for 1000 h at the same high current density in 1 M KOH + 0.5 M NaCl. These outstanding electrochemical performances highlight the potential of the CuCoCrRuMo HEA catalyst for efficient and stable seawater electrolysis and the comprehensive utilization of seawater resources.

海水电解是一种很有前途的绿色制氢方法，但电解过程中海水的高腐蚀性和氢氧化镁的沉淀会使阴极迅速失活。因此，开发高效、低成本的电催化剂仍然是该领域的关键挑战。本研究开发了一种用于海水电解制氢的高熵合金（cuccrrumo HEA）催化剂，同时实现了海水中镁资源的回收。在OER过程中形成的MoO42−有效地排斥Cl−，减轻了催化剂的腐蚀。此外，Cr2O3还增强了催化剂的耐腐蚀性。该合金还通过排斥Mg2+，促进了Mg(OH)2的沉积和回收，实现了海水资源的有效利用。在1 M KOH条件下，当电流密度为1000 mA cm−2时，CuCoCrRuMo HEA的HER过电位为402 mV， OER过电位为450 mV。在1 M KOH + 0.5 M NaCl（模拟海水）条件下，HER过电位降至368 mV， OER过电位降至430 mV。此外，在1 M KOH + 0.5 M NaCl中，在相同的高电流密度下，保持HER和OER性能1000小时。这些优异的电化学性能凸显了cuccrrumo HEA催化剂在高效稳定的海水电解和海水资源综合利用方面的潜力。

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引用次数: 0

Operando-spectroscopy revealing interfacial two-coordinated ordered water in electrochemical activation of Ni(OH)₂ 操作光谱揭示界面双配位有序水在Ni(OH) 2电化学活化中的作用

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-28 DOI: 10.1016/j.actamat.2026.121970

Jingjuan Li , Zhiqi Zhu , Taowen Dong , Yuxiang Gao , Aofei Wei , Xiangyu Wu , Binbin Yang , Wenwen Li , Xiaolong Li , Tao Gan , Wei Zhang , Weitao Zheng

Elucidating the underlying mechanisms of electrochemical activation lays the foundation to establish structure-performance correlation in electrochemical systems. The available reports mainly focus on structural changes of the electrode itself. However, the corresponding evolution of the electrode-electrolyte interface; particularly the reconstruction of the interfacial hydrogen-bond networks, is frequently overlooked. Herein, we report the discovery of dynamic reconfigurations at the electrode-electrolyte interface in an electrochemical activation of the Ni(OH)₂ electrode. By using a suite of spectroscopy analyses, we demonstrate that the pristine Ni(OH)₂ can be dynamically converted into oxygen-vacancy rich Ni(OH)@NiOOH via two distinct stages. Furthermore, operando Raman spectroscopy and molecular dynamics (MD) simulations indicate that the interfacial four-coordinated, randomly distributed hydrogen-bonded water evolves into two-coordinated, more ordered hydrogen-bonded water. As a consequence, it facilitates OH^– transport across the electrode-electrolyte interface, leading to an extraordinary 5-fold enhancement of specific capacity. Our results reinvent the current cognition of electrochemical activation. That is, both the evolution of the electrode and the reconstruction of the interfacial water are fully involved, leads to the formation of a new solid-liquid interface.

阐明电化学活化的潜在机制是建立电化学体系结构-性能相关性的基础。现有的报道主要集中在电极本身的结构变化上。然而，电极-电解质界面的相应演变；特别是界面氢键网络的重建，经常被忽视。在此，我们报告了在Ni(OH)2电极的电化学活化中发现的电极-电解质界面的动态重新配置。通过一系列光谱分析，我们证明了原始的Ni(OH)2可以通过两个不同的阶段动态转化为富氧空位的Ni(OH)@NiOOH。此外，operando拉曼光谱和分子动力学（MD）模拟表明，界面上随机分布的四配位氢键水演变为更有序的两配位氢键水。因此，它促进了OH -在电极-电解质界面上的传输，从而使比容量提高了5倍。我们的研究结果重塑了目前对电化学活化的认知。即电极的演化和界面水的重建都充分参与，导致新的固液界面的形成。

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引用次数: 0

Tailoring microstructures with mild magnetic-field processing: A case study of CuNiFe alloys 用微磁场加工定制微结构：以CuNiFe合金为例

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-25 DOI: 10.1016/j.actamat.2026.121965

X. Zhang , C.D. Woodgate , G. Hadjipanayis , J.B. Staunton , L.H. Lewis

Combined experimental and computational investigations of the CuNiFe spinodal system confirm that application of a mild magnetic field during thermal treatment alters elemental redistribution and the resulting microstructure, relative to that obtained from zero-field annealing. Spinodal decomposition of a Cu₄₀Ni₄₂Fe₁₈ alloy was initiated during thermal treatment at 773 K, conducted either under zero field or modest (60 mT) magnetic field conditions for up to 200 h. Periodic (∼10 nm) chemical modulations into Cu-rich and NiFe-rich regions were observed under both conditions, with the amplitude and wavelength of the segregated regions increasing with treatment time. However, magnetic field annealing resulted in a more than twofold increase in the amplitude of elemental modulations relative to zero-field conditions – consistent with enhanced diffusional fluxes during spinodal decomposition – while the modulation wavelength remained largely unaffected. These microstructural differences are reflected in various extrinsic magnetic properties. In parallel, first-principles DFT calculations indicate that long-range ferromagnetic order, as induced by an applied magnetic field, substantially alters the strength and nature of atomic interactions, enhancing the thermodynamic instability of the CuNiFe solid solution. Collectively, these results suggest that incorporating a mild (millitesla-level) magnetic field – distinct from the strong (tesla-level) fields commonly used in prior studies – during thermal processing has the potential to deliver enhanced control of microstructures for targeted engineering outcomes.

结合CuNiFe spinodal系统的实验和计算研究证实，相对于零场退火，在热处理过程中施加弱磁场改变了元素的再分配和最终的微观结构。Cu40Ni42Fe18合金在773 K的温度下，在零场或中等（60 mT）磁场条件下进行了长达200小时的Spinodal分解。在这两种条件下，都观察到富cu和富nife区域的周期性（~ 10 nm）化学调制，分离区域的振幅和波长随着处理时间的增加而增加。然而，磁场退火导致相对于零场条件下元素调制幅度增加了两倍以上，这与spinodal分解期间增强的扩散通量一致，而调制波长基本未受影响。这些微观结构的差异反映在不同的外在磁性能上。与此同时，第一性原理DFT计算表明，在外加磁场的诱导下，远程铁磁有序极大地改变了原子相互作用的强度和性质，增强了CuNiFe固溶体的热力学不稳定性。总的来说，这些结果表明，在热加工过程中加入一个温和的（毫特斯拉级）磁场——不同于之前研究中常用的强（特斯拉级）磁场——有可能为目标工程结果提供增强的微观结构控制。

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引用次数: 0

Rb(Cd,Zn)4As3 as a new n-type Zintl phase thermoelectric compound Rb(Cd,Zn) 4 As 3是一种新型n型Zintl相热电化合物

IF 9.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2026-04-01 Epub Date: 2026-01-27 DOI: 10.1016/j.actamat.2026.121968

Keigo Ono , Yosuke Goto , Hidetomo Usui , Masayuki Murata , Satoshi Tsutsui , Kazuhiko Kuroki , Yoichi Kamihara , Chul-Ho Lee

Despite 143-Zintl phase was recently found to be a new family of high performance thermoelectric compounds, the lack of n-type restricts its potential for application in practical thermoelectric modules. Here we report a novel n-type 143-Zintl phase compound of RbCd

_{4 - x}

Zn

_{x}

As

_{3}

as a counterpart. The samples were prepared using solid-state reactions and densified via hot pressing. The Seebeck coefficients were negative, demonstrating that they represent n-type conductors. The Hall carrier concentration was found to decrease upon Zn doping, suggesting that the band gap opened upon doping, consistent with the results of first-principles calculations. Notably, the Hall mobility was extremely high, namely

μ_{H}

= 2.0 × 10³ cm²/Vs at

T

= 300 K, originating from the electrical conductivities of the Cd 5s and As 4p electrons. On the other hand, a low lattice thermal conductivity was obtained, i.e., the minimum value of 0.56 W/mK (

x

= 0.4) at

T

= 624 K, and the maximum value of the dimensionless figure-of-merit (

Z T

) was determined to be 0.43 (

x

= 0.4) at

T

= 620 K. These results pave the way for the development of high-performance n-type thermoelectric compounds of the 143-Zintl phase.

尽管最近发现143-Zintl相是一种新的高性能热电化合物，但缺乏n型限制了其在实际热电模块中的应用潜力。在这里，我们报道了一种新的RbCd4 - xZnxAs3的n型143-Zintl相化合物作为对应物。样品采用固相反应制备，热压致密化。塞贝克系数为负，表明它们代表n型导体。发现掺杂Zn后霍尔载流子浓度降低，表明掺杂后带隙打开，与第一性原理计算结果一致。值得注意的是，在T = 300 K时，由于Cd 5s和As 4p电子的导电性，霍尔迁移率极高，μH = 2.0 × 103 cm2/Vs。另一方面，获得了较低的晶格导热系数，即在T = 624 K时最小值为0.56 W/mK (x = 0.4)，在T = 620 K时无因次优值（ZT）的最大值为0.43 （x = 0.4）。这些结果为143-Zintl相高性能n型热电化合物的开发铺平了道路。

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引用次数: 0