Acta Materialia最新文献_第6页

Boosting Low-E electro-strain via high-electronegativity B-site substitution in lead-free K0.5Na0.5NbO3-based ceramics 通过在无铅 K0.5Na0.5NbO3 基陶瓷中取代高电负性 B 晶位来增强低电应变

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-28 DOI: 10.1016/j.actamat.2024.120520

Jie Wang, Binquan Wang, Geng Huangfu, Hongjie Zhang, Yiping Guo

Lead-free piezoelectric actuators emerge as promising substitutes for their lead-containing counterparts to address environmental concerns. However, they often confront a trade-off between low driving electric fields and high electro-strain. Herein, a novel strategy to boost electro-strain under low electric fields is proposed by doping high-electronegativity B-site atoms into perovskite potassium sodium niobate-based ceramics. Our findings reveal that high-electronegativity B-site atoms elevate the covalency of B-O bonding, softening the short-range repulsion and introducing local multiphase coexistence. This leads to more nanoscale domain structures and lower coercive field, thereby enabling large strains to be produced at lower electric fields. Notably, a substantial 0.2 % bipolar electro-strain and 0.1 % unipolar electro-strain under 10 kV cm^-1 is achieved in Sr, Sb co-doped potassium sodium niobate ceramics, with a broad working frequency and temperature range, as well as excellent fatigue resistance. This study unveils innovative insights into designing lead-free piezoelectric ceramics with remarkable electro-strain performance and low driving electric field, promising a significant advancement in lead-free piezoelectric materials science and piezoelectric actuators.

为解决环境问题，无铅压电致动器有望取代含铅致动器。然而，它们往往面临低驱动电场和高电应变之间的权衡。在此，我们提出了一种新策略，通过在过氧化物铌酸钠钾基陶瓷中掺入高电负性 B 位原子来提高低电场下的电应变。我们的研究结果表明，高电负性 B 位原子提高了 B-O 键的共价性，软化了短程斥力并引入了局部多相共存。这导致了更多的纳米级畴结构和更低的矫顽力场，从而能在较低的电场下产生较大的应变。值得注意的是，在 10kV cm-1 的电压下，掺杂硒和锑的铌酸钾钠陶瓷可产生 0.2% 的双极性电应变和 0.1% 的单极性电应变，而且工作频率和温度范围更广，抗疲劳性也非常出色。这项研究揭示了设计具有显著电应变性能和低驱动电场的无铅压电陶瓷的创新见解，有望在无铅压电材料科学和压电致动器领域取得重大进展。

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引用次数: 0

Unveiling the mechanisms of ultra-low thermal and oxygen-ion conductivity in entropy-stabilized ferroelastic rare-earth tantalates 揭示熵稳定铁弹性稀土钽酸盐的超低热导率和氧离子导率机制

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-28 DOI: 10.1016/j.actamat.2024.120523

Jun Wang , Qianqian Jin , Peng Wu , ZiFan Zhao , Zhenhua Ge , Xiaoyu Chong , Jing Feng

Most current thermal and environmental barrier coating materials, even with high relative densities, exhibit high oxygen-ion conductivity, which accelerates the oxidation of the substrate and ultimately results in coating failure. Herein, high-entropy rare-earth tantalates ((6RE_1/6)TaO₄) are presented with lattice distortion that causes local disruption of the ordered stacking of oxygen-ions and cations, thereby resulting in reduced oxygen-ion and thermal conductivities. The oxygen-ion conductivity of (6RE_1/6)TaO₄ decreased by three to five orders of magnitude compared with that of 8YSZ and was further decreased by the high-entropy effect compared with that of single-RE RETaO₄ from 600 to 900 ℃, which is the result of strong bond strength, severe lattice distortion, high oxygen vacancy clusters and a high concentration of immobile vacancies. Furthermore, the intrinsic thermal conductivity of (6RE_1/6)TaO₄ is 14.3∼40.5 % less than single-RE RETaO₄ and ∼65.3 % lower than that of 8YSZ at 1200 °C. It also presents lower intrinsic thermal conductivity across the temperature range of 100 to 1200 °C. This is the result of scattering by Umklapp processes, oxygen vacancies, lattice distortions, ferroelastic domains and dislocations. Entropy-stabilized (6RE_1/6)TaO₄ also has excellent thermal stability and mechanical properties, thereby making it a promising thermal and environmental barrier coating material.

目前大多数隔热和环境阻隔涂层材料，即使具有较高的相对密度，也表现出较高的氧离子传导性，这会加速基底的氧化，最终导致涂层失效。这里介绍的高熵稀土钽酸盐（(6RE1/6)TaO4）具有晶格畸变，会导致氧离子和阳离子的有序堆叠发生局部破坏，从而降低氧离子和热导率。与 8YSZ 相比，(6RE1/6)TaO4 的氧离子电导率降低了 3 至 5 个数量级，与 600 至 900 ℃ 的单RE RETaO4 相比，高熵效应进一步降低了其氧离子电导率，这是强结合强度、严重晶格畸变、高氧空位簇和高浓度不动空位的结果。此外，在 1200 ℃ 时，(6RE1/6)TaO4 的本征热导率比单RE RETaO4 低 14.3∼40.5%，比 8YSZ 低 65.3%。在 100 至 1200°C 的温度范围内，它的本征热导率也较低。这是由 Umklapp 过程、氧空位、晶格畸变、铁弹性域和位错散射造成的。熵稳定的（6RE1/6）TaO4 还具有出色的热稳定性和机械性能，因此是一种很有前途的隔热和环境屏障涂层材料。

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引用次数: 0

Electron work function guided tailoring of (W4-x, Mx)C4 /doped Ni matrix interfacial bonding: Insights from first-principles calculations 电子功函数引导下的(W4-x, Mx)C4 /掺杂镍基体界面键合：第一原理计算的启示

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-26 DOI: 10.1016/j.actamat.2024.120511

P. Aghdasi, D.Y. Li

Heavy tungsten carbide (WC) may cause inhomogeneous distributions in WC-metal matrix composite hardfacing overlays, thus negatively affecting its performance as reinforcement. WC can be lightened by partially substituting W with lighter metals, e.g., Mo and Cr, while maintaining its strength. However, the bonding between modified WC and matrix metals such as nickel (a typical metal-matrix for overlays) is uncertain. This article reports a study on the interfacial bonding between (W_4-x, M_x)C₄ (M=Mo or Cr) and Ni matrix via first-principle calculations. Different atomic interactions i.e., metal-metal and metal-carbon interactions, at the interface were studied to understand the interfacial bonding through analyses of electron work function (EWF), electron localization function, electronic density of states, bond order, and net charge. It was demonstrated that the lighter (W_4-x, M_x)C₄ carbides exhibit strong bonding with Ni, comparable to or even stronger than that of WC/Ni interface, and the interfacial bonding includes covalent, ionic and metallic bond components. It is demonstrated that the interfacial bonding can be tuned by doping elements in the Ni matrix with different EWFs, e.g., Mn, Cu, Au, Pt, and Se. Efforts have been made to verify a hypothesis that EWF is an indicator, which can be used to guide selecting effective dopants for tailoring the interfacial bond strength.

厚重的碳化钨（WC）可能会导致碳化钨-金属基复合材料硬面覆盖层中的不均匀分布，从而对其作为增强材料的性能产生负面影响。在保持碳化钨强度的前提下，可以用更轻的金属（如钼和铬）部分替代碳化钨。然而，改性碳化钨与基体金属（如镍，一种典型的覆盖层金属基体）之间的粘合情况尚不确定。本文通过第一原理计算，报告了 (W4-x, Mx)C4 （M=钼或铬）与镍基体之间的界面键合研究。通过对电子功函数（EWF）、电子局域函数、电子态密度、键序和净电荷的分析，研究了界面上不同的原子相互作用，即金属-金属和金属-碳相互作用，以了解界面成键情况。研究表明，较轻的（W4-x, Mx）C4 碳化物与镍的结合力很强，与 WC/Ni 界面的结合力相当甚至更强，界面结合包括共价键、离子键和金属键成分。研究表明，可以通过在镍基体中掺入不同 EWF 的元素（如锰、铜、金、铂和硒）来调整界面键合。我们努力验证了一个假设，即 EWF 是一个指标，可用于指导选择有效的掺杂剂来调整界面结合强度。

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引用次数: 0

Unusual deformation mechanisms evoked by hetero-zone interaction in a heterostructured FCC high-entropy alloy 异质结构 FCC 高熵合金中异质区相互作用诱发的异常变形机制

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-26 DOI: 10.1016/j.actamat.2024.120516

Jiahao Li , Xinkai Ma , Kejie Lu , Yanfei Wang , Yuntian Zhu

Understanding the synergistic mechanical effects of heterostructured materials remains challenging due to the complexities in the underlying deformation mechanisms, which are usually diverse, activated at different length scales and possibly interacting. Here, we unravel a deformation fundamental for heterostructures: in addition to the direct contribution on strength, hetero-zone interaction and the development of long-range internal stress could assist in evoking extra plastic mechanisms that are difficult to activate in their homogeneous counterparts. Specifically, the deformation of a heterostructure in Al_0.1CoCrFeNi alloy, featuring nanostructured hard lamellae embedded in fine-grained soft matrix, is taken as an example for study. Drawing from experimental insights, the long-range internal stress buildup at elastoplastic transition stage due to intense dislocation pile-ups against hetero-zone boundary, which increases yield strength significantly, is theoretically analyzed. At the plastic stage, the high internal stress helps to activate phase transformation in the fine-grained zones, and the inter-zone constraint leads to form dispersed stable strain bands in the nanostructured zones. These extra mechanisms, together with enhanced deformation twinning, facilitate work hardening and coordinate the strain partitioning between zones, imparting improved ductility at high flow stress. These findings indicate a principle for heterostructural design: introducing strong hetero-zone interaction to enhance internal stress and thereby invoke new deformation mechanisms.

由于基本变形机制的复杂性，理解异质结构材料的协同机械效应仍具有挑战性，这些机制通常多种多样，在不同的长度尺度上激活，并可能相互作用。在此，我们揭示了异质结构的变形基本原理：除了对强度的直接贡献外，异质区相互作用和长程内应力的发展还有助于唤起同质材料难以激活的额外塑性机制。具体来说，我们以 Al0.1CoCrFeNi 合金中的异质结构变形为例进行研究，该异质结构的特点是纳米结构的硬薄片嵌入细粒软基体中。借鉴实验结果，从理论上分析了在弹塑性转变阶段，由于异质区边界的密集位错堆积而导致的长程内应力积聚，从而显著提高了屈服强度。在塑性阶段，高内应力有助于激活细晶粒区的相变，而区间约束则导致在纳米结构区形成分散的稳定应变带。这些额外的机制与增强的变形孪晶一起，促进了加工硬化，并协调了各区之间的应变分配，从而提高了高流动应力下的延展性。这些发现表明了异质结构设计的一个原则：引入强大的异质区相互作用来增强内应力，从而激发新的变形机制。

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引用次数: 0

Corrigendum to “Critical impacts of thermodynamic instability and short-range order on deformation mechanisms of VCoNi medium-entropy alloy” [Acta Materialia 277 (2024) 120190] 热力学不稳定性和短程有序性对钴镍中熵合金变形机制的关键影响》[Acta Materialia 277 (2024) 120190]更正

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-25 DOI: 10.1016/j.actamat.2024.120490

T.H. Chou , W.P. Li , L.Y. Zhu , F. Zhu , X.C. Li , J. Huang , Y.X. Wang , R. Zhou , W.Y. Chen , J.H. Luan , Y.L. Zhao , Z.X. Wu , F.R. Chen , J.C. Huang , P.K. Liaw , X.L. Wang , T. Yang

引用次数: 0

Strategic lattice manipulation in transition metal nitrides for improved solubility 在过渡金属氮化物中进行晶格策略性处理以提高溶解度

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-25 DOI: 10.1016/j.actamat.2024.120514

Rebecca Janknecht , Nikola Koutná , Katharina Weiss , Eleni Ntemou , Szilárd Kolozsvári , Paul H. Mayrhofer , Rainer Hahn

In this study, we propose a new concept for achieving metastable ternary transition metal nitride solid solutions, focusing on face centered cubic (fcc) structured Ti(N,B) as a model system. Combining non-reactive magnetron sputtering with computational analysis, we develop a microalloying strategy to manipulate the metallic sublattice, thereby influencing the solubility of B in the non-metal sublattice. We show that imposed tensile strain on the fcc-TiN lattice facilitates the solubility of B, with a 1.5 % strain enabling the incorporation of ∼28.5 at.% B at the non-metal sublattice. Conversely, compressive strain hinders the formation of the fcc-Ti(N,B) solid solution, highlighting the importance of lattice manipulation in controlling solubility. At the same time, our experimental findings reveal that adding larger atoms, such as Zr, to the metal sublattice enhances the solubility of B in fcc-TiN more effectively (∼2 at.% Zr proves to be sufficient to solute 10 at.% B in the fcc-TiN lattice) than smaller atoms, like Cr or similar-sized Ti atoms. The size effect of the alloying atoms on the B solubility is further supported by radial distribution function analysis, showing lower local lattice distortions for Zr compared to Cr.

在本研究中，我们以面心立方（fcc）结构的 Ti(N,B) 为模型系统，提出了实现可陨落三元过渡金属氮化物固溶体的新概念。结合非反应性磁控溅射和计算分析，我们开发了一种微合金化策略来操纵金属亚晶格，从而影响 B 在非金属亚晶格中的溶解度。我们的研究表明，在 fcc-TiN 晶格上施加拉伸应变有利于硼的溶解，1.5% 的应变可使非金属亚晶格中的硼含量达到 28.5%。相反，压缩应变会阻碍 fcc-Ti（N，B）固溶体的形成，这突出了晶格操作在控制溶解度方面的重要性。同时，我们的实验结果表明，与较小的原子（如 Cr 或类似大小的 Ti 原子）相比，在金属亚晶格中加入较大的原子（如 Zr）能更有效地提高 B 在 fcc-TiN 中的溶解度（事实证明，在 fcc-TiN 晶格中，2% 的 Zr 就足以溶解 10%的 B）。合金原子的大小对硼溶解度的影响得到了径向分布函数分析的进一步支持，该分析表明 Zr 的局部晶格畸变低于 Cr。

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引用次数: 0

Buckling of thin films: Lateral growth and kinetic evolution of telephone cords 薄膜的弯曲电话线的横向生长和动力学演变

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-24 DOI: 10.1016/j.actamat.2024.120505

Senjiang Yu , Ibrahim Goda , Guillaume Parry , Julien Durinck , Yong Ni , Christophe Coupeau

We conduct a thorough investigation of the lateral growth and kinetic evolution of telephone cord buckles within thin films, employing both experimental and numerical techniques. Our exploration begins with in-situ experiments conducted on annealed silicon nitride films, aimed at capturing empirical data on the formation and evolution of these distinctive patterns. These experiments yield valuable insights into the morphological changes of telephone cords, such as wave flipping and merging, which lead to the enlargement of buckles at double wavelengths and widths. Subsequently, we employ a combined approach of geometrically nonlinear plate modeling and surface-based cohesive interface framework within a finite element numerical model to analyze the interplay between buckling-induced delamination and growth triggered by mode mixity-dependent interfacial toughness. Through this integrated approach, we effectively capture the mutual evolution of buckling and delamination occurrences, thus highlighting their inherently dynamic nature. Our numerical simulations show that the width and wavelength of telephone cords are doubled, consistent with experimental findings.

我们采用实验和数值技术，对薄膜内电话线扣的横向生长和动力学演变进行了深入研究。我们的探索从在退火氮化硅薄膜上进行的原位实验开始，旨在捕捉这些独特图案形成和演变的经验数据。通过这些实验，我们对电话线的形态变化（如波翻转和合并）有了宝贵的认识，这些变化导致双波长和双宽度的倒扣扩大。随后，我们在有限元数值模型中采用几何非线性板建模和基于表面的内聚界面框架相结合的方法，分析了降伏诱发的分层和由模式混合性相关界面韧性引发的生长之间的相互作用。通过这种综合方法，我们有效地捕捉到了屈曲和分层发生的相互演变，从而突出了它们内在的动态性质。我们的数值模拟结果表明，电话线的宽度和波长都增加了一倍，这与实验结果一致。

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引用次数: 0

Investigating the thermal decomposition of BP into B12P2: experimental insights and kinetic modelling at high temperatures 研究 BP 热分解为 B12P2：高温下的实验启示和动力学建模

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-24 DOI: 10.1016/j.actamat.2024.120495

Yves Tahan , Olivier Rapaud , Nicolas Pradeilles , Pierre Carles , Alexandre Maître , Sarah Dine , Dominique Vrel , Hicham Moutaabbid , Yann Le Godec , Cécile Genevois , Mathieu Allix

This study investigates the thermal decomposition of BP into B₁₂P₂, with a particular focus on the heterogeneous solid-gas mechanism involving BP powders synthesized via self-propagating high temperature reactions. Various techniques, including XRD, TGA, SEM, TEM, EELS and SAED, were combined to examine morphological and structural changes at different temperatures. The results reveal an ignition temperature for decomposition at 1120 °C, beyond which BP grains undergo fragmentation into smaller particles, accompanied by the release of phosphorous gases (P_2(g), P_4(g)). Additionally, Rietveld refinements on thermally treated powders facilitated the determination of advancement rate values of the decomposition reaction under different isothermal conditions. Based on these kinetic data obtained at 1300 °C, a one-process nucleation-growth model with instantaneous nucleation and anisotropic growth has be established. In particular, the law, which describes the process for a spherical grain with inward development and a reaction occurring at the internal interface as the step determining the rate, displayed a strong correlation coefficient, offering novel insights into the kinetic evolution of the BP to B₁₂P₂ conversion. These results contribute to a deeper understanding of the thermal decomposition process and its underlying elementary mechanisms.

本研究探讨了 BP 热分解为 B12P2 的过程，尤其关注通过自蔓延高温反应合成的 BP 粉末的异质固气机理。研究结合了 XRD、TGA、SEM、TEM、EELS 和 SAED 等多种技术，考察了不同温度下的形态和结构变化。结果显示，分解的点火温度为 1120°C，超过这一温度，BP 晶粒会碎裂成更小的颗粒，同时释放出磷气体（P2(g)、P4(g)）。此外，对热处理过的粉末进行里特维尔德细化，有助于确定不同等温条件下分解反应的推进率值。根据这些在 1300°C 下获得的动力学数据，建立了一个具有瞬时成核和各向异性生长的单过程成核-生长模型。特别是，该模型描述了球形晶粒向内发展的过程，以及在内部界面发生的反应作为决定速率的步骤，显示出很强的相关系数，为 BP 向 B12P2 转化的动力学演变提供了新的见解。这些结果有助于加深对热分解过程及其基本机制的理解。

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引用次数: 0

Anisotropy of plastic flow in Zr-2.5Nb pressure tube material analysed using a viscoplastic self-consistent approach 利用粘弹性自稳方法分析 Zr-2.5Nb 压力管材料中塑料流动的抗变形性

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-24 DOI: 10.1016/j.actamat.2024.120503

N. Christodoulou , C.N. Tomé

Plastic anisotropy is observed during plastic flow in samples from the axial and transverse directions of Zr-2.5Nb pressure tubes used in CANDU¹ nuclear reactors tested in uniaxial tension. Plastic anisotropy was also measured in shear by testing in torsion ‘mini’ pressure tubes from the same material. Room temperature results from these experiments were analysed using a visco-plastic self-consistent model that takes into account the crystallographic texture of the material and allows for the single crystal work hardening behaviour to be described by means of a deformation law specific to each slip system.

The visco-plastic self-consistent model was used to derive: (i) the evolution with strain of the critical resolved shear stress values consistent with prismatic, basal and pyramidal dislocation glide, (ii) the evolution of slip system activity as a function of strain, and (iii) the values of Hill's plastic anisotropy coefficients that are consistent with the observed anisotropy of yielding and their dependence on accumulated strain. The model also allows for the prediction of the components of the flow stress tensor that cannot be measured experimentally and their dependence on the work hardening behaviour of pressure tube material. Moreover, the yield surface after different amounts of plastic strain was calculated using the visco-plastic self-consistent model, compared to the one that results from using the Hill's anisotropy coefficients. Our work exposes the limitations of the Hill ellipsoid for describing plastic yield when microstructural evolution is present.

在 CANDU1 核反应堆中使用的 Zr-2.5Nb 压力管的轴向和横向样品中观察到塑性各向异性。此外，还通过对相同材料的 "迷你 "压力管进行扭转测试，测量了其在剪切过程中的塑性各向异性。使用粘弹性自洽模型对这些实验的室温结果进行了分析，该模型考虑了材料的晶体学纹理，并允许通过每个滑移系统特有的变形定律来描述单晶加工硬化行为。粘塑自洽模型用于推导：(i) 与棱柱形、基座形和金字塔形位错滑移一致的临界分辨剪切应力值随应变的演变；(ii) 滑移系统活动随应变的演变；(iii) 希尔塑性各向异性系数的值，这些值与观察到的屈服各向异性及其对累积应变的依赖性一致。该模型还可以预测无法通过实验测量的流动应力张量成分及其与压力管材料加工硬化行为的关系。此外，与使用希尔各向异性系数得出的屈服面相比，使用粘弹性自洽模型计算了不同塑性应变量后的屈服面。我们的研究揭示了希尔椭圆体在微结构演变时描述塑性屈服的局限性。

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引用次数: 0

Modeling of the perovskite nickelate SmNiO3 nucleation from amorphous thin films: A Volmer's thermodynamical approach 非晶态薄膜中的包晶镍酸盐 SmNiO3 成核模型：沃尔默热力学方法

IF 8.3 1区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Acta Materialia

Pub Date : 2024-10-24 DOI: 10.1016/j.actamat.2024.120509

Silvère Barrat, Zil Fernández-Gutiérrez, Carlos Calvo-Mola, Pierre-Antoine Tostivint, Stéphanie Bruyère, David Pilloud, Fabien Capon

We present a thermodynamical model based on Volmer's nucleation theory adapted to the case of the perovskite nickelate SmNiO₃ crystallization (SNO) from an amorphous (aSNO) thin film. This amorphous phase is synthesized via reactive magnetron sputtering and then subsequently annealed in air at temperatures between 725 and 925 K to crystallize it. This model allows to predict the theoretical nucleation rate of the crystallized perovskite phase according to the annealing temperature, the type of the nucleation (homogeneous and heterogeneous mechanisms) and to estimate some physical and thermodynamical data related to this transformation. A theoretical evaluation of the nucleation rate shows that the optimum temperature for crystallization is close to 800 K for which the nucleation rate can reach 10²¹ m^-3.s^-1 if considering both homogeneous and heterogeneous nucleation mechanisms. As the annealing temperature moves away from 800 K, the theoretical nucleation rate drops drastically, as observed experimentally by X-ray Diffraction (XRD) when we annealed 200 nm thick aSNO films. The good agreement between the presented model and the experimental crystallization results allows us to numerically evaluate some physical parameters not yet reported to date in the literature for SNO perovskites such as the surface energy between the amorphous and the crystallized SNO phases, the strain energy when the crystallization occurs and the enthalpy associated with crystallization.

我们提出了一个基于沃尔默成核理论的热力学模型，该模型适用于从无定形（aSNO）薄膜结晶出包晶态镍酸盐 SmNiO3（SNO）的情况。这种非晶相是通过反应磁控溅射合成的，随后在 725 至 925 K 的温度下进行空气退火，使其结晶。该模型可根据退火温度、成核类型（均相和异相机制）预测结晶包晶相的理论成核率，并估算与这种转变相关的一些物理和热力学数据。对成核率的理论评估表明，结晶的最佳温度接近 800 K，如果同时考虑均相和异相成核机制，成核率可达 1021 m-3.s-1。当退火温度远离 800 K 时，理论成核率会急剧下降，正如我们在退火 200 nm 厚的 aSNO 薄膜时通过 X 射线衍射 (XRD) 实验观察到的那样。所提出的模型与实验结晶结果之间的良好一致性使我们能够对迄今为止文献中尚未报道的 SNO 包晶体的一些物理参数进行数值评估，如无定形和结晶 SNO 相之间的表面能、发生结晶时的应变能以及与结晶相关的焓。

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引用次数: 0