Acta Materialia最新文献_第6页

Topological descriptors for disordered networks enable property prediction of multicomponent oxide glasses 无序网络的拓扑描述符使多组分氧化玻璃的性质预测成为可能

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

Acta Materialia

Pub Date : 2025-12-30 DOI: 10.1016/j.actamat.2025.121881

Xuan Ge , Daming Sun , Xiaowei Xu , Caijuan Shi , Zixing Zhen , Zhencai Li , Søren S. Sørensen , Christian G. Hoover , Lars R. Jensen , Randall E. Youngman , Yuanzheng Yue , Jianguo Li , Qiaodan Hu , Morten M. Smedskjaer

Establishing the structure-property relationships in multicomponent oxide glasses is highly challenging due to their inherent compositional and structural complexity. In this work, we present a topology-inspired structural decoding strategy to predict the structural impact on the properties of 45S5-based mixed alkali bioactive (MAB) glasses, a prototypical multicomponent system. Two novel topological descriptors, angular rigidity (

γ_{ac}

) and persistent homology matrix (

P H_{m}

), are introduced to map the structure-property landscape in MAB glasses. In detail,

γ_{ac}

accounts for the spatial averaging of network distortions, quantitatively predicting properties associated with network reorganization, such as glass transition temperature and hardness.

P H_{m}

evaluates the topological similarity between glass and crystalline phases, thereby characterizing the resistance of MAB glasses against crystallization (i.e., glass stability). Compared with conventional network analysis approaches, our two topological descriptors concurrently capture the higher-order nonlinear evolution of properties driven by the synergistic interplay between composition and cooling history. Importantly, these topological descriptors are derived solely from static glass structures generated via experimental measurements, suggesting potential utility for understanding diverse disordered materials. This work thus establishes a closed-loop framework that integrates synthesis, characterization, and predictive modelling for the specific 45S5-based MAB glass systems. The demonstrated ability to correlate topological features with distinct properties within this system represents a step towards the rational design of multicomponent oxide glasses.

由于其固有的成分和结构复杂性，建立多组分氧化玻璃的结构-性能关系是极具挑战性的。在这项工作中，我们提出了一种拓扑启发的结构解码策略来预测结构对基于45s5的混合碱生物活性（MAB）玻璃（一个典型的多组分体系）性能的影响。引入角刚度（γ - ac）和持久同源矩阵（PHm）这两个新颖的拓扑描述符来映射MAB玻璃的结构-性能景观。具体来说，γ - ac解释了网络扭曲的空间平均，定量预测了与网络重组相关的性质，如玻璃化转变温度和硬度。PHm评估玻璃和结晶相之间的拓扑相似性，从而表征MAB玻璃的抗结晶性（即玻璃稳定性）。与传统的网络分析方法相比，我们的两个拓扑描述符同时捕获了由成分和冷却历史之间的协同相互作用驱动的性质的高阶非线性演化。重要的是，这些拓扑描述符仅来源于通过实验测量产生的静态玻璃结构，这表明了理解各种无序材料的潜在效用。因此，这项工作建立了一个闭环框架，集成了合成、表征和预测建模的特定45s5基MAB玻璃系统。在该系统中，将拓扑特征与不同性质相关联的能力表明，向合理设计多组分氧化玻璃迈出了一步。

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引用次数: 0

Nanoscale interfacial melting enables bonding during high velocity microparticle impacts 纳米级界面熔化使高速微粒撞击过程中的键合成为可能

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

Acta Materialia

Pub Date : 2025-12-30 DOI: 10.1016/j.actamat.2025.121888

Muhammad Shehryar Khan , Christopher A. Schuh

Melting during high-velocity particle impact has been understood to be typically detrimental to bonding by lowering the strength at the interface and promoting rebound before solidification can occur. Here we establish a possible remedy to this challenge: by dramatically restricting the volume of molten material, its resolidification is accelerated, effectively forming a nanoscale, braze-type joint during impact. In-situ single particle impact imaging is combined with post-mortem structural and chemical analyses to reveal a regime where adhesion is governed not by extensive plastic deformation, but by the kinetics of melt layer resolidification. These findings redefine the role of melting in impact-based processes, establishing transient melting and rapid solidification as a viable strategy for engineering successful adhesion events.

在高速颗粒撞击过程中的熔化通常会降低界面强度，并在凝固发生之前促进回弹，从而对结合有害。在这里，我们提出了一种可能的解决方案：通过大幅限制熔融材料的体积，加速其再凝固，在冲击过程中有效地形成纳米级钎焊式接头。现场单颗粒冲击成像与死后结构和化学分析相结合，揭示了粘合不是由广泛的塑性变形控制的，而是由熔体层再凝固动力学控制的。这些发现重新定义了熔化在基于冲击的过程中的作用，建立了瞬态熔化和快速凝固作为工程成功粘合事件的可行策略。

引用次数: 0

Growth kinetic study of Cr-coated zirconium alloy interface during α-phase thermal aging α-相热时效过程中cr包覆锆合金界面生长动力学研究

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

Acta Materialia

Pub Date : 2025-12-29 DOI: 10.1016/j.actamat.2025.121883

Yang Liu , Linfeng Wang , Bo Li , Chun Cheng , Yi Zhao , Lu Wu , Xiaoyong Wu , Sho Kano , Hiroaki Abe , Huilong Yang

Preparation of a Cr-coating onto zirconium (Zr) alloy provides an enhanced safety margin for fuel cladding in nuclear power plants. However, the simultaneously introduced Cr-Zr interface, at which the interfacial microstructure and structure will undergo inevitable change under long-term high temperature operation, would play a critical role affecting the structural integrity of the cladding. In this study, the microstructural, chemical, and structural evolution growth kinetic behavior at the Cr-Zr interface in Cr-coated Zr alloy prepared by multi-arc ion plating was systematically studied after applying isothermal annealing treatments. Results show that an interlayer of a Zr(Fe,Cr)₂ intermetallic compound phase was formed after thermal aging, and the kinetic study of the interlayer growth gives rise to a diffusion activation energy of 88.1 kJ/mol, based on which, the mathematic model for predicting the interlayer growth was experimentally constructed. Presence of an Fe-poor ZrCr₂ nanocrystal strip is confirmed in the thermally-aged specimens. As a diffusion barrier, this nanocrystal strip decelerates the diffusion rate of Cr atoms, contributing to a retarded interlayer growth rate compared to a perfect Zr-Cr bilayer interface. Additionally, the grain growth in Cr-coating was observed upon thermal aging, and its kinetic growth model was constructed. Application of this model reveals that the Cr grain growth rate is relatively insignificant at normal operating temperature, nevertheless would become increasingly prominent at temperature >773 K. The hardness of the Zr(Fe, Cr)₂ phase interlayer is estimated as 11.8 ± 2.4 GPa, which is much greater than those at Zr-substrate and Cr-coating, inferring an enhanced failure risk at Cr-Zr interface during the long-term reactor operation. The obtained kinetic models of the interlayer growth and Cr-grain growth would help to guide the subsequent optimization of the surface coating and in-pile performance prediction of the ATF claddings.

在锆（Zr）合金上制备cr涂层，提高了核电站燃料包壳的安全裕度。但同时引入的Cr-Zr界面在长期高温作用下，其界面组织和结构将不可避免地发生变化，这将对熔覆层的结构完整性产生关键影响。本研究系统研究了经等温退火处理的多弧离子镀cr包覆Zr合金在Cr-Zr界面的组织、化学和组织演化生长动力学行为。结果表明：热时效后形成了一个Zr(Fe,Cr)2金属间化合物相的中间层，对中间层生长的动力学研究得出中间层生长的扩散活化能为88.1 kJ/mol，并在此基础上实验建立了预测中间层生长的数学模型。热时效试样中存在贫铁ZrCr2纳米晶条。作为扩散屏障，这种纳米晶带减缓了Cr原子的扩散速度，与完美的Zr-Cr双层界面相比，导致层间生长速度减慢。此外，观察了cr涂层在热时效过程中的晶粒生长，并建立了其动力学生长模型。该模型的应用表明，Cr晶粒生长速率在正常工作温度下相对不显著，但在温度>；773 K时逐渐显著。Zr(Fe, Cr)2相中间层的硬度为11.8±2.4 GPa，远高于Zr衬底和Cr涂层的硬度，表明在反应器长期运行过程中，Cr-Zr界面的失效风险增大。所得的层间生长动力学模型和cr晶粒生长动力学模型有助于指导ATF包层后续的表面涂层优化和桩内性能预测。

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引用次数: 0

Super-ductile magnesium alloy at room temperature 室温下超延展性镁合金

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

Acta Materialia

Pub Date : 2025-12-29 DOI: 10.1016/j.actamat.2025.121884

He Li , Maowen Liu , Tengfei Xu , Ruifeng Zhang , Wu Gong , Takuro Kawasaki , Stefanus Harjo , Nobuhiro Tsuji , Qiuming Wei , Chaoli Ma , Ruixiao Zheng

The quest for lightweight and highly formable magnesium (Mg) alloys has drawn significant attention due to the growing demand for energy-efficient structural materials. Achieving high ductility in Mg at room temperature, which is critical for mass production of structural components, remains a formidable challenge despite decades of research. In this study, we demonstrate super-ductility in an ultrafine-grained (UFG) Mg alloy at room temperature. By microalloying with trace manganese (Mn) and reducing the grain size to sub-micron scale, Mg-0.3Mn (at. %) binary alloy achieves an exceptional room temperature tensile elongation of ∼135% at a quasi-static strain rate of ∼10⁻³ s⁻¹. Detailed microstructural analysis reveals that grain boundary (GB) sliding, rather than intragranular dislocation slip, is the dominant deformation mechanism in the UFG Mg-0.3Mn alloy. Unlike conventional alloying strategies that lead to GB pinning, the segregation of Mn element along GBs in a manner of nano-clusters could reduce interfacial bonding strength, acting as a lubricant to facilitate GB sliding and thus dramatically boost the ductility. This innovative GB engineering approach unlocks unprecedentedly remarkable deformability of Mg-based alloys at room temperature, paving the way for next-generation lightweight structural applications.

由于对节能结构材料的需求不断增长，对轻质和高成形镁合金的追求引起了人们的极大关注。尽管经过数十年的研究，在室温下实现镁的高延展性仍然是一个艰巨的挑战，这对于大规模生产结构部件至关重要。在这项研究中，我们证明了超细晶镁合金在室温下的超延展性。通过微量锰（Mn）的微合金化，将晶粒尺寸降至亚微米级，Mg-0.3Mn (at。%)二元合金的室温拉伸伸长率为~ 135%，准静态应变速率为~ 10 - 3 s - 1。详细的显微组织分析表明，UFG Mg-0.3Mn合金的主要变形机制是晶界滑移，而非晶内位错滑移。与传统合金化策略导致GB钉住不同，Mn元素沿GB以纳米团簇的方式偏析可以降低界面结合强度，作为润滑剂促进GB滑动，从而显著提高延展性。这种创新的GB工程方法解锁了mg基合金在室温下前所未有的卓越变形能力，为下一代轻质结构应用铺平了道路。

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引用次数: 0

Strengthening and deformation mechanisms in CoCrFeMnNi-based medium- and high-entropy alloys at room and cryogenic temperatures cocrfemnni基中高熵合金在室温和低温下的强化和变形机制

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

Acta Materialia

Pub Date : 2025-12-29 DOI: 10.1016/j.actamat.2025.121879

David D.S. Silva , Francisco G. Coury , Levente Vitos , Wei Li , Shuo Huang , Norbert Schell , Paul Mason , Amy J. Clarke , Michael J. Kaufman , Claudemiro Bolfarini

In this study, novel non-equiatomic CoCrFeMnNi-based medium- and high-entropy alloys (M/HEAs) were designed to activate distinct deformation mechanisms, including twinning-induced plasticity (TWIP) and/or transformation-induced plasticity (TRIP). Tensile tests were performed at 298 and 173 K. A variety of ex-situ multiscale characterization techniques, strengthening modeling, thermodynamic modeling (CALPHAD method), and ab initio density functional theory (DFT) calculations were employed to investigate the structural and microstructural evolution, enabling accurate identification of the strengthening and active deformation mechanisms operating in the M/HEAs. Strengthening modeling revealed that grain boundary strengthening was the primary contributor to yield strength at both temperatures. A key finding of this study is that a controlled FCC

\to

HCP martensitic transformation, associated with TRIP, enhances the strength-ductility balance even when the resulting HCP phase reaches ∼50% volume fraction. This demonstrates that TRIP-enabled metastability engineering is a promising strategy for designing high-performance M/HEAs for next-generation structural applications in energy, aerospace, and defense.

在这项研究中，设计了一种新型的非等原子cocrfemnni基中高熵合金（M/HEAs）来激活不同的变形机制，包括孪生诱导塑性（TWIP）和/或变形诱导塑性（TRIP）。在298和173 K下进行拉伸试验。采用多种非原位多尺度表征技术、强化建模、热力学建模（CALPHAD方法）和从头算密度泛函理论（DFT）计算来研究M/HEAs的结构和微观结构演变，从而准确识别M/HEAs中的强化和主动变形机制。强化模型显示，晶界强化是两种温度下屈服强度的主要贡献者。本研究的一个关键发现是，与TRIP相关的可控FCC→HCP马氏体相变，即使产生的HCP相达到~ 50%的体积分数，也能增强强度-塑性平衡。这表明，在能源、航空航天和国防领域的下一代结构应用中，启用trip的亚稳态工程是设计高性能M/HEAs的一种很有前途的策略。

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引用次数: 0

A general kinetic framework for dislocation mobility derived from probabilistic cellular automaton simulations of the kink-pair mechanism 从扭结对机制的概率元胞自动机模拟中导出了位错迁移的一般动力学框架

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

Acta Materialia

Pub Date : 2025-12-27 DOI: 10.1016/j.actamat.2025.121876

Cathy Bing , Philip Eisenlohr

Dislocation mobility laws are essential components of dislocation-density-based crystal plasticity models. For dislocations governed by the kink-pair mechanism, however, existing formulations are typically limited to specific regimes due to the complex coupling between stochastic kink-pair nucleation and lateral kink migration. In this study, we develop a general kinetic framework that expresses the average dislocation velocity as a function of mechanism-level variables: positive/negative kink-pair nucleation rates, kink migration velocity, dislocation segment length, critical kink-pair width, and kink height. Probabilistic cellular automaton simulations are used to capture the behavior of conceptual dislocation segments between the limiting conditions of migration outpacing nucleation on the one end and nucleation outpacing migration on the other. An elementary functional form that captures the system dynamics is suggested and fitted against the simulation results. This framework remains valid for arbitrary combinations of the six variables and is, therefore, compatible with any admissible constitutive relations that describe their stress and temperature dependence. Comparisons with established approaches and experimental results confirm the robustness and physical consistency of the formulation, making it broadly applicable to material systems in which dislocation motion is governed by the kink-pair mechanism.

位错迁移率规律是基于位错密度的晶体塑性模型的重要组成部分。然而，对于由扭结对机制控制的位错，由于随机扭结对成核和侧向扭结迁移之间的复杂耦合，现有的公式通常局限于特定的情况。在这项研究中，我们开发了一个通用的动力学框架，将平均位错速度表示为机制水平变量的函数：正/负扭结对成核速率、扭结迁移速度、位错段长度、临界扭结对宽度和扭结高度。利用概率元胞自动机模拟捕捉了迁移速度超过成核和成核速度超过迁移速度这两种极限条件之间的概念位错段的行为。提出了捕捉系统动力学的基本函数形式，并与仿真结果进行了拟合。该框架仍然适用于六个变量的任意组合，因此，与描述其应力和温度依赖性的任何可接受的本构关系兼容。与已建立的方法和实验结果的比较证实了该公式的鲁棒性和物理一致性，使其广泛适用于位错运动由扭结对机制控制的材料体系。

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引用次数: 0

Multiscale investigation of early-stage boundary sliding mechanisms in lath martensite of low-carbon-steel 低碳钢板条马氏体早期边界滑动机制的多尺度研究

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

Acta Materialia

Pub Date : 2025-12-27 DOI: 10.1016/j.actamat.2025.121877

Shuang Gong , Junya Inoue

Previous studies have identified two primary deformation mechanisms in lath martensite under tensile loading, particularly highlighting intra-lath crystallographic slip based on direct dislocation observations. In this study, a multiscale approach was employed to further advance the understanding of boundary sliding in low-carbon lath martensite. High-resolution digital image correlation (HR-DIC), molecular dynamics (MD) simulations, and electron channeling contrast imaging (ECCI) were integrated to investigate the boundary sliding process in the early stage of plastic deformation. Both macro-scale HR-DIC analysis and atomic MD simulation revealed that the sub-block and twin boundaries preferentially accommodate boundary sliding. Systematic shear simulations on twist boundaries representing various variant pairs clarified that the critical resolved shear stress (CRSS) for low-angle boundaries with dense hexagonal dislocation networks correlates with the ratio of <111> to <100> screw dislocation lengths within the network. Furthermore, simulations demonstrated that mobile “in-out” edge dislocations interact with these interfacial networks, facilitating misorientation changes that promote boundary sliding. Complementary submicron-scale ECCI observations provide experimental evidence for the presence of such dislocation networks near substructure boundaries.

先前的研究已经确定了板条马氏体在拉伸载荷下的两种主要变形机制，特别强调了基于直接位错观察的板条内晶体滑移。本研究采用多尺度方法进一步加深了对低碳板条马氏体边界滑动的认识。结合高分辨率数字图像相关（HR-DIC）、分子动力学（MD）模拟和电子通道对比成像（ECCI）研究了塑性变形早期的边界滑动过程。宏观尺度的HR-DIC分析和原子MD模拟表明，子块边界和双边界优先适应边界滑动。系统地对代表不同变对的扭转边界进行剪切模拟，表明具有密集六边形位错网络的低角度边界的临界分解剪切应力（CRSS）与网络内<；111>；与<；100>；螺位错长度之比相关。此外，模拟表明，移动的“输入-输出”边缘位错与这些界面网络相互作用，促进了取向错误的变化，从而促进了边界滑动。互补的亚微米尺度ECCI观测为这种位错网络在亚结构边界附近的存在提供了实验证据。

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引用次数: 0

High-temperature phase transformation mechanisms in the U-2.5Mo-2.5Ti-5.0Zr (U-MT5Z) quaternary alloy u -2.5 mo -2.5 ti -5.0 zr （U-MT5Z）四元合金高温相变机理

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

Acta Materialia

Pub Date : 2025-12-27 DOI: 10.1016/j.actamat.2025.121875

Wangwei Ru , Kun Yang , Weiqian Zhuo , Mingliang Kang , Danwen Qin , Yibo Wang , Xiaobin Tang

Metallic fuels are considered ideal candidates for fast reactors due to their excellent neutron economy, manufacturability, and high burnup potential. To date, the development of metallic fuels has been restricted by their relatively low structural and phase stability. The current research focuses on the high-temperature behavior of the quaternary metallic fuel (U-2.5Mo-2.5Ti-5.0Zr) by fundamentally understanding the thermally driven elemental and microstructural evolution using multiscale advanced material characterization techniques and first-principles calculations. Experimental results reveal that the addition of Ti and Mo significantly broadens the thermal stability range of the high-temperature γ-U phase, suppressing its thermal decomposition during thermal cycling. Furthermore, both DFT calculations and experimental results indicate that the formation of a Zr-Ti compound effectively retards zirconium migration, thereby improving microstructural stability under high-temperature scenarios. This research reveals the mechanisms of phase transformations and the microstructural evolution of quaternary uranium-based metallic fuels at the atomic scale, thereby advancing the theoretical foundation for fuel design and performance optimization in advanced fast-reactor fuel systems.

金属燃料因其优异的中子经济性、可制造性和高燃耗潜力而被认为是快堆的理想候选燃料。迄今为止，金属燃料的发展一直受到其相对较低的结构和相稳定性的限制。目前的研究重点是通过多尺度先进材料表征技术和第一性原理计算，从根本上了解热驱动元素和微观结构的演变，从而研究季元金属燃料（U-2.5Mo-2.5Ti-5.0Zr）的高温行为。实验结果表明，Ti和Mo的加入显著拓宽了高温γ-U相的热稳定范围，抑制了其在热循环过程中的热分解。此外，DFT计算和实验结果都表明，Zr-Ti化合物的形成有效地延缓了锆的迁移，从而提高了高温条件下微观结构的稳定性。本研究在原子尺度上揭示了季系铀基金属燃料的相变机理和微观结构演化，为先进快堆燃料系统的燃料设计和性能优化提供了理论基础。

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引用次数: 0

Thermally induced formation of nanotwins in magnetron sputtered TaB1+Δ films 磁控溅射TaB1+x薄膜中热诱导纳米孪晶的形成

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

Acta Materialia

Pub Date : 2025-12-26 DOI: 10.1016/j.actamat.2025.121873

Katarína Viskupová , Branislav Grančič , Tomáš Fiantok , Peter Švec , Richard Vrablec , Tomáš Roch , Martin Truchlý , Viktor Šroba , Vitalii Izai , Zuzana Hájovská , Marián Mikula

Transition metal monoborides represent a structurally diverse class of materials known for their excellent thermal stability and mechanical properties. Synthesis by magnetron sputtering at temperatures ∼500 °C usually results in the development of highly disordered or amorphous films. In this work we investigate the structural evolution of sputtered TaB_1+Δ films induced by vacuum annealing. High-resolution scanning transmission electron microscopy reveals that crystallization of the disordered material into orthorhombic TaB-Cmcm structure is accompanied by formation of (110) stacking faults promoting the development of crystalline twins. The slight boron overstoichiometry in the films is accommodated by the structure through incorporation of B-rich planar defects resulting in local formation of hexagonal TaB₂-P6/mmm phase. Experimental results are supported by density functional theory calculations demonstrating that twinning in the TaB-Cmcm structure is energetically favorable and thus a natural phenomenon. Importantly, our results indicate that overstoichiometry in TaB_1+Δ is not likely to be caused by Ta vacancies, suggesting that planar and intergrowth-type defects represent the dominant mechanisms for incorporation of excess B.

过渡金属单硼化物代表了一种结构多样的材料，以其优异的热稳定性和机械性能而闻名。在温度~ 500°C的磁控溅射合成通常导致高度无序或非晶膜的发展。本文研究了真空退火诱导的溅射TaB1+Δ薄膜的结构演变。高分辨率扫描透射电子显微镜显示，无序材料结晶为正交TaB-Cmcm结构，并伴有（110）层错的形成，促进了孪晶的发育。通过加入富硼平面缺陷，导致局部形成六方的TaB2-P6/mmm相，可以调节薄膜中轻微的硼超化学计量。实验结果得到了密度泛函理论计算的支持，表明TaB-Cmcm结构中的孪生在能量上是有利的，因此是一种自然现象。重要的是，我们的结果表明，TaB1+Δ中的过度化学计量不太可能是由Ta空位引起的，这表明平面和互生长型缺陷是过量B结合的主要机制。

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引用次数: 0

High-entropy design for improved CBTa-based piezoelectric ceramics and high-temperature ultrasonic applications 改进cbta基压电陶瓷的高熵设计及高温超声应用

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

Acta Materialia

Pub Date : 2025-12-25 DOI: 10.1016/j.actamat.2025.121870

Hao Chen , Chao Jiang , Voon-Kean Wong , David Boon Kiang Lim , Jie Yin , Zhi Tan , Kui Yao , Jianguo Zhu

Aurivillius-type bismuth layer-structured ferroelectric CaBi₂Ta₂O₉ (CBTa) material has shown potential for high-temperature piezoelectric ultrasonic transducer application. However, practical implementation is limited by the relatively low piezoelectric coefficient, high sintering temperature, and a lack of ultrasonic experimental verification. In this work, we introduce an A/B-site substituted CBTa system based on a high-entropy strategy and significantly enhance the piezoelectric constant d₃₃ from 5.4 pC/N in pure CBTa ceramic to 12.1 pC/N in Ca_0.74Li_0.03Na_0.1Ce_0.04Bi_2.09Ta_1.4Nb_0.2W_0.2Ti_0.2O₉ (CLNCBTaNWT-2) ceramic, attributed to the enhanced ferroelectricity with the effective incorporation of the substituting ions into the CBTa lattice. The sintering temperature is significantly reduced from 1200 °C to 900 °C due to the reduction in the energy barrier for grain boundary diffusion. In addition, our ultrasonic experiments demonstrate that the symmetric zero-order mode (S₀) and antisymmetric zero-order mode (A) ultrasonic wave modes generated by obtained CLNCBTaNWT-2 ceramic remained high signal-to-noise ratios of 12.2 dB and 19.7 dB, respectively, up to 400 °C. These results demonstrate that the CBTa-based ceramic system designed with high-entropy strategy is promising for high-temperature ultrasonic structural health monitoring (SHM) applications.

aurivillius型铋层结构铁电材料CaBi2Ta2O9 （CBTa）在高温压电超声换能器方面具有潜在的应用前景。然而，由于压电系数较低、烧结温度较高，以及缺乏超声实验验证，实际实施受到限制。在这项工作中，我们引入了一种基于高熵策略的A/ b位取代CBTa体系，并将压电常数d33从纯CBTa陶瓷的5.4 pC/N显著提高到Ca0.74Li0.03Na0.1Ce0.04Bi2.09Ta1.4Nb0.2W0.2Ti0.2O9 （CLNCBTaNWT-2）陶瓷的12.1 pC/N，这是由于取代离子有效地结合到CBTa晶格中而增强的铁电性。由于晶界扩散的能垒降低，烧结温度从1200℃显著降低到900℃。此外，我们的超声波实验表明，所获得的CLNCBTaNWT-2陶瓷产生的对称零阶模式（S0）和反对称零阶模式（A0）超声波模式在高达400 °C时仍然保持高信噪比，分别为12.2 dB和19.7 dB。这些结果表明，采用高熵策略设计的基于cbta的陶瓷系统在高温超声结构健康监测（SHM）中具有广阔的应用前景。

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引用次数: 0