Computational Materials Science最新文献_第2页

Simulation of stochastic discrete dislocation dynamics in ductile Vs brittle materials 韧性材料与脆性材料中随机离散位错动力学模拟

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-27 DOI: 10.1016/j.commatsci.2024.113541

Santosh Chhetri , Maryam Naghibolhosseini , Mohsen Zayernouri

Defects are inevitable during the manufacturing processes of materials. Presence of these defects and their dynamics significantly influence the responses of materials. A thorough understanding of dislocation dynamics of different types of materials under various conditions is essential for analysing the performance of the materials. Ductility of a material is directly related with the movement and rearrangement of dislocations under applied load. In this work, we look into the dynamics of dislocations in ductile and brittle materials using simplified two dimensional discrete dislocation dynamics (2D-DDD) simulation. We consider Aluminium (Al) and Tungsten (W) as representative examples of ductile and brittle materials respectively. We study the velocity distribution, strain field, dislocation count, and junction formation during interactions of the dislocations within the domain. Furthermore, we study the probability densities of dislocation motion for both materials. In mesoscale, moving dislocations can be considered as particle diffusion, which are often stochastic and super-diffusive. Classical diffusion models fail to account for these phenomena and the long-range interactions of dislocations. Therefore, we propose the nonlocal transport model for the probability density and obtained the parameters of nonlocal operators using a machine learning framework.

在材料的制造过程中，缺陷是不可避免的。这些缺陷的存在及其动态对材料的反应有很大影响。透彻了解不同类型材料在各种条件下的位错动力学对于分析材料的性能至关重要。材料的延展性与位错在外加载荷下的运动和重新排列直接相关。在这项工作中，我们使用简化的二维离散位错动力学（2D-DDD）模拟来研究韧性和脆性材料中的位错动力学。我们将铝（Al）和钨（W）分别作为韧性和脆性材料的代表。我们研究了位错在域内相互作用时的速度分布、应变场、位错数量和结点形成。此外，我们还研究了这两种材料的位错运动概率密度。在中尺度中，位错运动可视为粒子扩散，通常具有随机性和超扩散性。经典扩散模型无法解释这些现象和差排的长程相互作用。因此，我们提出了概率密度的非局部传输模型，并利用机器学习框架获得了非局部算子的参数。

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引用次数: 0

Data driven studies of magnetic ground state and transition temperature in two-dimensional magnets 二维磁体中磁性基态和转变温度的数据驱动研究

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-26 DOI: 10.1016/j.commatsci.2024.113542

Weidong Wang , Runhu Xiao , Shiwei Zhu , Changsheng Song

The magnetic characteristics of two dimensional (2D) van der Waals (vdW) magnets are governed by a delicate balance among various factors, posing a significant challenge in the design of novel 2D magnets. In this work, we employ a data-driven approach to investigate the magnetic properties of monolayers composed A₂B₂X₆, building upon the well-established ferromagnetic Cr₂Ge₂Te₆. Here, using random forest and gradient lift regression algorithms, we perform a high-throughput scan of 696 materials from a database to classify ferromagnetic and antiferromagnetic compounds based on their magnetic ground state. First principles-based computations and Monte Carlo simulations, followed by Heisenberg model-based, are employed to estimate the transition temperature (

T_{c}

) of these magnets. The classification accuracy reaches approximately 84%, while the regression accuracy is around 81%. Our results not only enrich the family of 2D magnets and present high-temperature ferromagnetic materials but also offer insights into the realization of high temperature magnets. This work paves the way for accelerating the discovery of novel magnetic compounds with high transition temperatures for spintronic applications.

二维（2D）范德华（vdW）磁体的磁特性受制于各种因素之间的微妙平衡，这给新型 2D 磁体的设计带来了巨大挑战。在这项工作中，我们采用了一种数据驱动的方法来研究由 A2B2X6 组成的单层材料的磁性能，它建立在已被证实具有铁磁性的 Cr2Ge2Te6 的基础之上。在这里，我们使用随机森林和梯度提升回归算法，对数据库中的 696 种材料进行了高通量扫描，根据它们的磁基态对铁磁性和反铁磁性化合物进行了分类。我们采用基于第一性原理的计算和蒙特卡罗模拟，以及基于海森堡模型的计算，来估算这些磁体的转变温度（Tc）。分类准确率约为 84%，回归准确率约为 81%。我们的研究结果不仅丰富了二维磁体和高温铁磁材料家族，还为高温磁体的实现提供了启示。这项工作为加速发现自旋电子应用中具有高转变温度的新型磁性化合物铺平了道路。

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引用次数: 0

Atomic mechanisms of oxidative behavior of ferrochromium alloys by water-oxygen environment 水氧环境下铬铁合金氧化行为的原子机制

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-26 DOI: 10.1016/j.commatsci.2024.113567

Zongxiao Zhu , Jialong Wang , Dingfeng Qu , Zhilong Zhao , Hui Tan , Qichun Sun , Tao Zheng

The formation of chromium-rich oxide layers on the surface of Fe-Cr alloys significantly impacts their performance at elevated temperatures. Understanding the formation process of these oxide layers at the atomic scale is crucial for further elucidating oxidation behavior, though it presents substantial challenges. In this study, ReaxFF molecular dynamics simulations were used to investigate the oxidation behavior of Fe-Cr alloys in high temperature water vapor and oxygen environments. The results demonstrate that chromium atoms are the primary contributors to the oxidation process, with Cr atoms diffusing to the surface more readily than iron atoms, leading to uneven stress distribution and creating high-stress regions near the Cr atoms. Additionally, hydrogen atoms generated from the breakdown of water molecules infiltrate the alloy matrix, promoting the creation, movement, and clustering of cation and anion vacancies, thereby enhancing oxidation reactions in high-temperature, humid conditions. The study further analyzes electron transfer during single-atom chemical reactions and explores the linear relationship between varying Cr content (10 %–30 %) and oxidation behavior under identical environmental conditions. These findings provide an important theoretical basis for optimizing the performance of Fe-Cr alloys for applications in high temperature environments.

铁铬合金表面富铬氧化层的形成极大地影响了其在高温下的性能。在原子尺度上了解这些氧化层的形成过程对于进一步阐明氧化行为至关重要，但这也是一项巨大的挑战。本研究采用 ReaxFF 分子动力学模拟来研究铁铬合金在高温水蒸气和氧气环境中的氧化行为。结果表明，铬原子是氧化过程的主要成分，铬原子比铁原子更容易扩散到表面，从而导致应力分布不均匀，并在铬原子附近形成高应力区。此外，水分子分解产生的氢原子渗入合金基体，促进阳离子和阴离子空位的产生、移动和聚集，从而增强了高温潮湿条件下的氧化反应。研究进一步分析了单原子化学反应过程中的电子转移，并探讨了在相同环境条件下，不同铬含量（10%-30%）与氧化行为之间的线性关系。这些发现为优化铁铬合金在高温环境中的应用性能提供了重要的理论依据。

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引用次数: 0

N-body interatomic potential for molecular dynamics simulations of V-Cr-Nb-Mo-Ta-W system 用于 V-Cr-Nb-Mo-Ta-W 体系分子动力学模拟的 N 体原子间势能

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-25 DOI: 10.1016/j.commatsci.2024.113533

V.N. Maksimenko , A.G. Lipnitskii , V.N. Saveliev , A.I. Kartamyshev , A.V. Vyazmin , D.O. Poletaev

Diffusion in high-entropy alloys is an important phenomenon controlling its evolution during exploitation. Its detailed investigation, especially at elevated temperatures, is a challenging task. Molecular dynamics simulations facilitate significantly findings in this area and provide valuable insights into it. The key part of the molecular dynamics is the interatomic potential representing the dependence of the potential energy of the system of atoms on their coordinates. To correctly calculate the diffusivity, the potentials should satisfy several criteria such as an accurate reproduction of the melting point and thermal expansion. The last one is crucial as diffusion is strongly influenced by the size factor. We used the N-body approach to construct the interatomic potential for the high-entropy alloy V-Cr-Nb-Mo-Ta-W system, which consists of the potentials for pure elements and binary systems constituting the six-component one. The constituting potentials reproduce structure, elastic, defect and melting properties of pure elements and concentration dependent properties of binary systems. As a test for the VNbMoTaW and VCrNbMoTaW alloys, we calculated the forces acting on atoms for a set of different compositions and obtained the adequate agreement with the density functional theory (DFT) results. Additionally, we computed the surface and excess screw dislocation energies for both pure elements and alloys. The experimental surface energy values averaged over the elements show remarkable agreement (less than 10%) for the equiatomic VNbMoTaW and VCrNbMoTaW alloys. The excess screw dislocation energies of pure elements are predicted in qualitative agreement with DFT results, with tungsten having the highest energy and vanadium and niobium having the lowest. The corresponding values for five- and six-component alloys are less than DFT ones with deviations of 7% and 34%, respectively. They are close or moderately less than the energies averaged over pure elements.

高熵合金中的扩散是在开发过程中控制其演变的一个重要现象。对其进行详细研究是一项具有挑战性的任务，尤其是在高温条件下。分子动力学模拟大大促进了这一领域的研究成果，并提供了宝贵的见解。分子动力学的关键部分是原子间势能，它代表了原子系统的势能对其坐标的依赖关系。要正确计算扩散率，原子间势能应满足几个标准，如准确再现熔点和热膨胀。最后一个标准至关重要，因为扩散受尺寸因子的影响很大。我们使用 N-body 方法构建了高熵合金 V-Cr-Nb-Mo-Ta-W 系统的原子间位势，它由纯元素和二元系统的位势组成，构成了六组分位势。构成势再现了纯元素的结构、弹性、缺陷和熔化特性以及二元体系的浓度相关特性。作为对钒铌钽钨合金和钒铬铌钽钨合金的测试，我们计算了一组不同成分的原子作用力，结果与密度泛函理论（DFT）结果完全一致。此外，我们还计算了纯元素和合金的表面能和过量螺旋位错能。对于等原子 VNbMoTaW 和 VCrNbMoTaW 合金而言，元素平均表面能的实验值显示出显著的一致性（小于 10%）。纯元素的过量螺旋位错能量预测与 DFT 结果基本一致，其中钨的能量最高，钒和铌的能量最低。五组份和六组份合金的相应值低于 DFT 值，偏差分别为 7% 和 34%。它们接近或略低于纯元素的平均能量。

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引用次数: 0

Ultrafast water diffusion along the interface between oxidized and pristine regions in graphene oxide: Reactive molecular dynamics study 氧化石墨烯氧化区与原始区界面的超快水扩散：反应分子动力学研究

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-25 DOI: 10.1016/j.commatsci.2024.113461

Anastasia Zelenina , Ekaterina V. Skorb , Daria V. Andreeva , Nikita Orekhov

Graphene oxide (GO) is a promising membrane material due to its high water permeability. However, the exact physical mechanisms governing this process at the molecular level remain poorly understood, despite more than a decade of practical applications. In this article, we use classical molecular dynamics with the reactive potential ReaxFF to study the mobility of water molecules intercalated in GO and analyze the influence of its structure on diffusion processes. We highlight the previously unmentioned role of the interfacial area between oxidized and pristine graphene regions, which, according to our calculations, may be responsible for the ultrafast water transport observed in GO. This diffusion exhibits characteristics of a ballistic regime, suggesting another possible mechanism underlying GO’s high water permeability.

氧化石墨烯（GO）具有很高的透水性，是一种很有前途的膜材料。然而，尽管经过十多年的实际应用，人们对分子水平上支配这一过程的确切物理机制仍然知之甚少。在这篇文章中，我们利用经典分子动力学和反应势 ReaxFF 研究了插层在 GO 中的水分子的流动性，并分析了其结构对扩散过程的影响。根据我们的计算，氧化石墨烯区域和原始石墨烯区域之间的界面区域可能是在 GO 中观察到的超快水传输的原因。这种扩散表现出弹道机制的特征，暗示了 GO 高透水性的另一种可能机制。

引用次数: 0

Structural, electronic, and optical properties of two-dimensional bilayer MgCl2 intercalated with Be and Mg single atom: Insulator to semiconductor transformation 插有铍和镁单原子的二维双层氯化镁的结构、电子和光学特性：绝缘体到半导体的转变

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-24 DOI: 10.1016/j.commatsci.2024.113468

Nasir Shehzad , Ismail Shahid , Fazle Subhan , Waheed-Ur-Rahman , Meng-Qu Cai

The intercalation of alkaline earth metals Be and Mg single atoms in the two-dimensional (2D) bilayer MgCl₂ (B-MgCl₂) system has been investigated in the present study, showing their effect on the structural, electronic, and optical characteristics using density functional theory (DFT) computation. The electronic behavior of B-MgCl₂ has been identified as that of an insulator. In contrast, the behavior of the Be and Mg-intercalated B-MgCl₂ shifts to that of a narrow band gap semiconductor, with the band gap measured at 1.00 eV and 0.98 eV for Be-MgCl₂ and Mg-MgCl₂, respectively. This notable change in electronic behavior presents intriguing opportunities for practical applications in optoelectronics and semiconductor devices. Moreover, the intercalation of Be and Mg atoms significantly influences the built-in electric field of the B-MgCl₂ system. The rise in the built-in electric field after the intercalation of Be and Mg atoms further emphasizes the potential for manipulating the electronic properties of this system for specific applications, potentially enabling improved charge transport and optoelectronic properties. Besides altering the electronic band structure, the intercalation of Be and Mg single atoms into the bilayer MgCl₂ system also induces prominent peaks in the infrared, visible, and ultraviolet (UV) regions of the solar spectrum. These observed optical characteristics represent a crucial aspect in the development of intercalation compounds for optoelectronic nanodevices, as they offer enhanced absorption and emission properties that can be harnessed in a wide range of technological applications and opening up avenues for innovation in the field of semiconductors.

本研究采用密度泛函理论（DFT）计算方法，研究了碱土金属 Be 和 Mg 单原子在二维双层氯化镁（B-MgCl2）体系中的掺杂，显示了它们对结构、电子和光学特性的影响。B-MgCl2 的电子行为被确定为绝缘体的电子行为。相比之下，掺杂了铍和镁的 B-MgCl2 的行为则转变为窄带隙半导体，铍-MgCl2 和镁-MgCl2 的带隙分别为 1.00 eV 和 0.98 eV。电子行为的这一显著变化为光电子学和半导体器件的实际应用提供了引人入胜的机会。此外，铍原子和镁原子的掺杂极大地影响了 B-MgCl2 体系的内置电场。掺杂铍原子和镁原子后内置电场的升高进一步强调了针对特定应用操纵该体系电子特性的潜力，从而有可能改善电荷传输和光电特性。除了改变电子能带结构外，铍和镁单原子掺杂到双层氯化镁体系中还会在太阳光谱的红外线、可见光和紫外线（UV）区域产生突出的峰值。观察到的这些光学特性是开发光电纳米器件用插层化合物的一个重要方面，因为它们具有增强的吸收和发射特性，可用于广泛的技术应用，并为半导体领域的创新开辟了道路。

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引用次数: 0

Pressure waves induced by the bcc-hcp phase transition in dynamically loaded single crystal iron 动态加载单晶铁中 bcc-hcp 相变诱发的压力波

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-24 DOI: 10.1016/j.commatsci.2024.113559

N. Amadou , T. de Rességuier

Molecular Dynamics simulations have been used to investigate the dynamic response of single crystal iron to ramp compression along the [001] crystallographic direction, with a focus on the coupling between the propagation and interaction of pressure waves and the phase transformation process. In particular, we report an original observation at the atomic level of release and recompression waves specifically induced by the phase transition. We provide a straightforward, physically-based explanation of the origin of these waves based on impedance mismatch between the parent, daughter, and mixed-phase region, and show how they depend directly on the kinetics of the transformation. This analysis may be generalized to other time-dependent phase transformations in other materials subjected to dynamic loading, and it is probably still valid at the much larger space and time scales encountered in experiments, which could have practical implications.

我们利用分子动力学模拟研究了单晶体铁沿 [001] 晶体学方向受到斜坡压缩时的动态响应，重点研究了压力波的传播和相互作用与相变过程之间的耦合关系。特别是，我们报告了在原子水平上观察到的由相变诱发的释放波和再压缩波。我们根据母相、子相和混合相区域之间的阻抗失配，对这些波的起源提供了一个简单明了的物理解释，并展示了它们是如何直接依赖于相变动力学的。这一分析可推广到其他材料在动态加载条件下发生的其他随时间变化的相变，而且在实验中遇到的更大空间和时间尺度上可能仍然有效，这可能会产生实际影响。

引用次数: 0

The effects of biaxial strain and sulfur/boron doping on the photocatalytic performance of the g-C3N5 system: A first-principles study 双轴应变和硫/硼掺杂对 g-C3N5 系统光催化性能的影响：第一原理研究

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-24 DOI: 10.1016/j.commatsci.2024.113560

Yongde Yao , Fujian Tang , Shangtong Yang

Strain and doping are effective methods for enhancing the intrinsic properties of the photocatalyst g- C₃N₅. This paper investigates the electronic properties, optical characteristics, and changes in Gibbs free energy of g-C₃N₅ under the combined effects of biaxial strain and sulfur/boron (S/B) doping through first-principles calculations. By calculating the formation energy of the doping system, the optimal doping positions for B/S are identified. The results indicate that intrinsic g-C₃N₅ exhibits indirect band gap semiconductor properties with a band gap of 1.851 eV. In contrast, S/B doping reduces the band gap, with the S-doped g-C₃N₅ system (S-g-C₃N₅) displaying direct band gap semiconductor properties and a band gap of 1.677 eV. The application of tensile or compressive strain induces a red shift or blue shift in the absorption spectra of both the intrinsic g-C₃N₅ system and the doped system. Tensile strain positions the band edges of all systems favorably, enhancing carrier mobility and redox capability. This study provides valuable insights for the development of photocatalytic carbon nitride through atomic doping and strain modulation.

应变和掺杂是增强光催化剂 g-C3N5 固有特性的有效方法。本文通过第一原理计算，研究了在双轴应变和硫/硼（S/B）掺杂的共同作用下 g-C3N5 的电子特性、光学特征和吉布斯自由能的变化。通过计算掺杂体系的形成能，确定了 B/S 的最佳掺杂位置。结果表明，本征 g-C3N5 具有间接带隙半导体特性，带隙为 1.851 eV。相比之下，S/B 掺杂降低了带隙，S 掺杂的 g-C3N5 系统（S-g-C3N5）显示出直接带隙半导体特性，带隙为 1.677 eV。施加拉伸或压缩应变会导致本征 g-C3N5 系统和掺杂系统的吸收光谱发生红移或蓝移。拉伸应变使所有体系的带边缘位置发生有利的变化，从而提高了载流子的迁移率和氧化还原能力。这项研究为通过原子掺杂和应变调制开发光催化氮化碳提供了宝贵的见解。

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引用次数: 0

Developing Mode I cohesive traction laws for crystalline Ultra-high molecular weight polyethylene interphases using molecular dynamics simulations 利用分子动力学模拟开发超高分子量聚乙烯结晶相间的 I 型内聚牵引定律

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-24 DOI: 10.1016/j.commatsci.2024.113552

I.A. Mukherjee , M.A.N. Dewapriya , J.W. Gillespie Jr. , J.M. Deitzel

Ultra-high molecular weight polyethylene fiber with a diameter of 17 µm contains over 100,000 fibrils with diameters ranging from 10 to 100 nm. These fibrils can exhibit various relative rotations around the axial direction, forming interphases between distinct crystal planes. Fiber failure can occur due to defibrillation governed by the adhesion between fibrils. In this study, adhesion is quantified through cohesive traction laws that describe the strength, progressive damage, and energy absorption during fibril separation. We predict Mode I cohesive traction laws for polyethylene (PE) interphases between crystals with various orientations using molecular dynamics (MD) simulations. Results were compared with the stress-displacement response of perfect bulk crystals of similar thickness. Surface effects primarily manifested in the outermost layer of PE chains where molecular structure deviates from the bulk crystal structure resulting in a higher surface energy. This resulted in an interphase thickness equivalent to the thickness of two PE chain layers (1.2 nm). The disturbed crystal structure at the interfaces led to a 32% reduction in peak traction and a 46% reduction in energy absorption compared to the perfect bulk crystal. Additionally, results show that strain rate does not have an influence of the traction laws over the range of 10⁸ s⁻¹ to 10¹⁰ s⁻¹. The MD-based traction-separation relations were used to fit parameters for a cohesive zone model. The interphase traction laws predicted in this study can be used as interface properties to bridge length scales in multiscale simulations of defibrillation.

直径为 17 微米的超高分子量聚乙烯纤维含有 10 万多条直径在 10 纳米到 100 纳米之间的纤维。这些纤维可围绕轴向进行各种相对旋转，在不同的晶面之间形成相间。纤维失效的原因可能是纤维之间的粘附力导致的颤动。在本研究中，粘附力通过内聚牵引定律进行量化，该定律描述了纤维分离过程中的强度、渐进损伤和能量吸收。我们利用分子动力学（MD）模拟预测了不同取向晶体间聚乙烯（PE）相间的模式 I 内聚牵引定律。结果与厚度相似的完美块状晶体的应力-位移响应进行了比较。表面效应主要体现在聚乙烯链的最外层，其分子结构偏离了块状晶体结构，导致表面能较高。这导致相间厚度相当于两个聚乙烯链层的厚度（1.2 纳米）。与完美的块状晶体相比，界面上紊乱的晶体结构导致峰值牵引力降低 32%，能量吸收降低 46%。此外，研究结果表明，在 108 s-1 到 1010 s-1 的范围内，应变速率对牵引力规律没有影响。基于 MD 的牵引分离关系被用来拟合内聚区模型的参数。本研究预测的相间牵引力定律可作为界面属性，在多尺度去颤模拟中弥合长度尺度。

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引用次数: 0

Utilizing deep learning for swift analysis of high-throughput spectroscopic ellipsometry data on anodized oxides of valve metals 利用深度学习快速分析阀金属阳极氧化物的高通量光谱椭偏仪数据

IF 3.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Computational Materials Science

Pub Date : 2024-11-23 DOI: 10.1016/j.commatsci.2024.113549

Xiaocha He , Juan Zuo , Wenhui Zhang , Andrei Ionut Mardare , Chaohui Guan , Tenglei Han , Dewei Zhao

Spectroscopic ellipsometry is a powerful high-throughput method for mapping the optical properties of combinatorial anodic oxides on alloys. However, the traditional ellipsometry data fitting using non-linear regression highly depends on correct assumptions and is tedious. The determination of the transition concentration of parent alloys that influences its properties to change, based on existing experimental data, without requiring further experimental measurements is also crucial for alloy engineering. Herein, anodic oxides grown on Nb-Ta and Nb-Ti combinatorial thin film binary libraries using a co-sputtering process are prepared (Nb concentration range is 10 ∼ 90 at.%, the oxidation voltage range is 1 ∼ 10 V). A deep learning method is developed to predict the refractive index (n) and extinction coefficient (k) of the oxide film from the ellipsometry data (606 groups). Four algorithms Convolutional Neural Networks (CNN), Convolutional Sequence-to-Sequence (ConvSeq2Seq), Temporal Convolutional Network (TCN), Gated Recurrent Unit Sequence-to-Sequence (GRUSeq2Seq) are compared. CNN achieves superior performance, yielding root mean square error values (RMSE) as low as 0.094 for predicting n and 0.037 for k. Additionally, a predictive model to reveal band-gap trends as a function of parent alloy composition and oxidation voltage at unmeasured locations along the libraries is developed. This approach helps identify the transition concentration that lead to optical property changes, thereby avoiding high experimental costs and potential experimental errors.

光谱椭偏仪是一种强大的高通量方法，可用于绘制合金上组合阳极氧化物的光学特性图。然而，使用非线性回归进行数据拟合的传统椭偏仪高度依赖于正确的假设，而且操作繁琐。在现有实验数据的基础上，确定影响母合金性质变化的过渡浓度，而不需要进一步的实验测量，这对合金工程也至关重要。本文采用共溅射工艺制备了生长在 Nb-Ta 和 Nb-Ti 组合薄膜二元库上的阳极氧化物（Nb 浓度范围为 10 ∼ 90 at.%，氧化电压范围为 1 ∼ 10 V）。我们开发了一种深度学习方法，从椭偏仪数据（606 组）中预测氧化膜的折射率（n）和消光系数（k）。比较了四种算法：卷积神经网络（CNN）、卷积序列到序列（ConvSeq2Seq）、时序卷积网络（TCN）、门控递归单元序列到序列（GRUSeq2Seq）。CNN 性能优越，预测 n 的均方根误差值 (RMSE) 低至 0.094，预测 k 的均方根误差值 (RMSE) 低至 0.037。此外，还开发了一个预测模型，以揭示带隙趋势与母合金成分和库沿线未测量位置的氧化电压的函数关系。这种方法有助于确定导致光学特性变化的转变浓度，从而避免高昂的实验成本和潜在的实验误差。

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引用次数: 0