Computational Materials Science最新文献_第4页

Time series forecasting of multiphase microstructure evolution using deep learning 利用深度学习对多相微观结构演变进行时间序列预测

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

Computational Materials Science

Pub Date : 2024-11-18 DOI: 10.1016/j.commatsci.2024.113518

Saurabh Tiwari , Prathamesh Satpute , Supriyo Ghosh

Microstructure evolution, which plays a critical role in determining materials properties, is commonly simulated by the high-fidelity but computationally expensive phase-field method. To address this, we approximate microstructure evolution as a time series forecasting problem within the domain of deep learning. Our approach involves implementing a cost-effective surrogate model that accurately predicts the spatiotemporal evolution of microstructures, taking an example of spinodal decomposition in binary and ternary mixtures. Our surrogate model combines a convolutional autoencoder to reduce the dimensional representation of these microstructures with convolutional recurrent neural networks to forecast their temporal evolution. We use different variants of recurrent neural networks to compare their efficacy in developing surrogate models for phase-field predictions. On average, our deep learning framework demonstrates excellent accuracy and speedup relative to the “ground truth” phase-field simulations. We use quantitative measures to demonstrate how surrogate model predictions can effectively replace the phase-field timesteps without compromising accuracy in predicting the long-term evolution trajectory. Additionally, by emulating a transfer learning approach, our framework performs satisfactorily in predicting new microstructures resulting from alloy composition and physics unknown to the model. Therefore, our approach offers a useful data-driven alternative and accelerator to the materials microstructure simulation workflow.

微观结构演化在决定材料性能方面起着至关重要的作用，通常采用高保真但计算成本高昂的相场方法进行模拟。为了解决这个问题，我们将微观结构演变近似视为深度学习领域的时间序列预测问题。我们的方法是以二元和三元混合物中的旋光分解为例，实施一种能准确预测微结构时空演变的经济高效的代理模型。我们的代用模型将卷积自动编码器与卷积递归神经网络相结合，前者用于降低这些微结构的维度表示，后者用于预测它们的时空演变。我们使用不同的递归神经网络变体来比较它们在开发相场预测代用模型方面的功效。平均而言，与 "地面实况 "相场模拟相比，我们的深度学习框架表现出卓越的准确性和速度。我们使用定量指标来证明代用模型预测如何在不影响长期演化轨迹预测准确性的情况下有效地替代相场时间步。此外，通过模仿迁移学习方法，我们的框架在预测模型未知的合金成分和物理特性所产生的新微观结构方面表现令人满意。因此，我们的方法为材料微观结构模拟工作流程提供了一种有用的数据驱动替代方法和加速器。

{"title":"Time series forecasting of multiphase microstructure evolution using deep learning","authors":"Saurabh Tiwari , Prathamesh Satpute , Supriyo Ghosh","doi":"10.1016/j.commatsci.2024.113518","DOIUrl":"10.1016/j.commatsci.2024.113518","url":null,"abstract":"<div><div>Microstructure evolution, which plays a critical role in determining materials properties, is commonly simulated by the high-fidelity but computationally expensive phase-field method. To address this, we approximate microstructure evolution as a time series forecasting problem within the domain of deep learning. Our approach involves implementing a cost-effective surrogate model that accurately predicts the spatiotemporal evolution of microstructures, taking an example of spinodal decomposition in binary and ternary mixtures. Our surrogate model combines a convolutional autoencoder to reduce the dimensional representation of these microstructures with convolutional recurrent neural networks to forecast their temporal evolution. We use different variants of recurrent neural networks to compare their efficacy in developing surrogate models for phase-field predictions. On average, our deep learning framework demonstrates excellent accuracy and speedup relative to the “ground truth” phase-field simulations. We use quantitative measures to demonstrate how surrogate model predictions can effectively replace the phase-field timesteps without compromising accuracy in predicting the long-term evolution trajectory. Additionally, by emulating a transfer learning approach, our framework performs satisfactorily in predicting new microstructures resulting from alloy composition and physics unknown to the model. Therefore, our approach offers a useful data-driven alternative and accelerator to the materials microstructure simulation workflow.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"247 ","pages":"Article 113518"},"PeriodicalIF":3.1,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142700024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Atomic structure modelling and its electronic states analysis of aluminium-related bismuth active centre (BAC-Al) in bismuth-doped optical fibre 掺铋光纤中与铝有关的铋活性中心（BAC-Al）的原子结构建模及其电子状态分析

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

Computational Materials Science

Pub Date : 2024-11-17 DOI: 10.1016/j.commatsci.2024.113520

Weirun Zhu , Baonan Jia , Shihao Sun , Pengfei Lu , Binbin Yan , Gang-Ding Peng

Bismuth-doped optical fibre (BDF) is a significant potential optical material for optical communication owing to its broad gain spectrum attributed to several bismuth active centres (BACs). In this work, we propose and study a simple model of aluminium-related bismuth active centre (BAC-Al) considering both Al and Bi in a member ring, using first principle methods. We analyse an Al-substituted member-ring with different Bi cases: substituted Bi¹⁺, Bi²⁺ and Bi³⁺ as well as interstitial Bi⁰, BiO, BiOH, and Bi₂O, and found that the interstitial Bi⁰ model produces the energy level diagram similar to that of BAC-Al. In addition, we studied the interstitial Bi⁰ in Al-substituted member-rings with different sizes and shapes. Based on our results, we confirmed that the interstitial Bi⁰ in an Al-substituted six-member-ring produces the best agreement in terms of BAC-Al energy level diagram.

掺铋光纤（BDF）由于具有多个铋有源中心（BAC）而具有宽广的增益谱，是一种极具潜力的光通信光学材料。在这项工作中，我们利用第一原理方法，提出并研究了一个简单的铝铋活性中心（BAC-Al）模型，该模型同时考虑了成员环中的铝和铋。我们分析了铝取代成员环中不同的 Bi 情况：取代 Bi1+、Bi2+ 和 Bi3+，以及间隙 Bi0、BiO、BiOH 和 Bi2O，发现间隙 Bi0 模型产生的能级图与 BAC-Al 相似。此外，我们还研究了不同尺寸和形状的 Al 取代成员环中的间隙 Bi0。根据我们的研究结果，我们证实了在铝取代的六元环中的间隙 Bi0 与 BAC-Al 能级图的一致性最好。

引用次数: 0

Effect of change in number of electrons to optical properties and surface plasmon resonance of noble metals 电子数变化对贵金属光学特性和表面等离子体共振的影响

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

Computational Materials Science

Pub Date : 2024-11-17 DOI: 10.1016/j.commatsci.2024.113519

Muhammad Riswan , Muhammad Arifin , Iman Santoso , Kenji Nawa , Kohji Nakamura , Edi Suharyadi

We have performed first-principles calculations to investigate the effect of change in the number of electrons on optical properties of Cu, Ag, and Au metals in visible and near-infrared energy ranges for surface plasmon resonance (SPR) applications in Kretschmann configuration. We find that an increase in the deviation of the number of electrons leads to a decrease in the real part of the optical conductivity,

σ_{1}

, and an increase in the real part of the dielectric constant,

ε_{1}

, for Ag and Au, but the decrease occurs in Cu. The changes in optical properties correspond to changes in the characteristics of the SPR curves; for Ag and Au, the SPR angle decreases, and the minimum reflectance increases, and in contrast, for Cu, the SPR angle increases, and the minimum reflectance decreases. Band-by-band decomposition analysis identifies that the prominent peak of optical conductivity arises from the interband transitions between the unoccupied uppermost d state and the conduction sp-like state, where an increase in the number of electrons causes a decrease in the prominent peak of optical conductivity in the metal, and vice versa. SPR simulation based on the calculated optical properties delineates the observed trend in SPR measurements. The results provide a scenario to improve the SPR biosensor’s performance by applying an electric field through the change in the number of electrons.

我们进行了第一原理计算，以研究电子数的变化对可见光和近红外能量范围内铜、银和金金属的光学特性的影响，这些金属可用于克雷奇曼构型的表面等离子体共振 (SPR)。我们发现，电子数偏差的增加会导致银和金的光导率 σ1 的实部减小和介电常数 ε1 的实部增大，但铜的光导率会减小。光学特性的变化与 SPR 曲线特性的变化相对应；对于银和金，SPR 角减小，最小反射率增大；相反，对于铜，SPR 角增大，最小反射率减小。逐带分解分析表明，光导率的突出峰值来自未占据的最上d态与传导sp样态之间的带间跃迁，电子数的增加会导致金属中光导率突出峰值的降低，反之亦然。根据计算出的光学特性进行的 SPR 模拟勾勒出了 SPR 测量中观察到的趋势。这些结果为通过电子数的变化施加电场来提高 SPR 生物传感器的性能提供了一种方案。

{"title":"Effect of change in number of electrons to optical properties and surface plasmon resonance of noble metals","authors":"Muhammad Riswan , Muhammad Arifin , Iman Santoso , Kenji Nawa , Kohji Nakamura , Edi Suharyadi","doi":"10.1016/j.commatsci.2024.113519","DOIUrl":"10.1016/j.commatsci.2024.113519","url":null,"abstract":"<div><div>We have performed first-principles calculations to investigate the effect of change in the number of electrons on optical properties of Cu, Ag, and Au metals in visible and near-infrared energy ranges for surface plasmon resonance (SPR) applications in Kretschmann configuration. We find that an increase in the deviation of the number of electrons leads to a decrease in the real part of the optical conductivity, <span><math><mrow><msub><mi>σ</mi><mn>1</mn></msub></mrow></math></span>, and an increase in the real part of the dielectric constant, <span><math><mrow><msub><mi>ε</mi><mn>1</mn></msub></mrow></math></span>, for Ag and Au, but the decrease occurs in Cu. The changes in optical properties correspond to changes in the characteristics of the SPR curves; for Ag and Au, the SPR angle decreases, and the minimum reflectance increases, and in contrast, for Cu, the SPR angle increases, and the minimum reflectance decreases. Band-by-band decomposition analysis identifies that the prominent peak of optical conductivity arises from the interband transitions between the unoccupied uppermost <em>d</em> state and the conduction <em>sp</em>-like state, where an increase in the number of electrons causes a decrease in the prominent peak of optical conductivity in the metal, and vice versa. SPR simulation based on the calculated optical properties delineates the observed trend in SPR measurements. The results provide a scenario to improve the SPR biosensor’s performance by applying an electric field through the change in the number of electrons.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"247 ","pages":"Article 113519"},"PeriodicalIF":3.1,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Ternary transition-metal nitride halide monolayers MNI (M = Zr, Hf) with low thermal conductivity and high thermoelectric figure of merit 具有低热导率和高热电性能的三元过渡金属氮化物卤化物单层 MNI（M = Zr、Hf

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

Computational Materials Science

Pub Date : 2024-11-16 DOI: 10.1016/j.commatsci.2024.113508

Radhakrishnan Anbarasan , Duckjong Kim , Jae Hyun Park

Machine learning-based approaches are promising in pursuing the thermal properties of two-dimensional materials. Here, a comprehensive study of thermal transport and thermoelectric properties of the

β

-form of ZrNI and HfNI monolayers, a family of ternary transition-metal nitride halides (TMNH), is presented by employing machine learning-based interatomic potential, Boltzmann transport theory, and first-principles calculations. The monolayer isolation and its stability are confirmed via cleavage energies, phonon dispersions, and ab initio molecular dynamics simulations. At room temperature, the lattice thermal conductivity of the ZrNI and HfNI monolayers are 7.8 W/(m

\cdot

K) and 11.7 W/(m

\cdot

K), respectively, which are considerably lower than those of typical 2D materials. The power factor of n-type doped ZrNI layer is 9 times higher than the HfNI monolayer due to high electrical conductivity of ZrNI. Also, the maximum figure of merit values of the n-type ZrNI always appears higher than the HfNI monolayer regardless of temperature. However, both the ZrNI and HfNI layers show superior thermoelectric properties over typical 2D materials. It reveals that the n-type ZrNI monolayer is a beneficial material for thermoelectric applications.

基于机器学习的方法在研究二维材料的热特性方面大有可为。本文通过采用基于机器学习的原子间势能、玻尔兹曼输运理论和第一性原理计算，全面研究了三元过渡金属氮化物卤化物（TMNH）家族中 ZrNI 和 HfNI 单层的 β 形式热输运和热电特性。通过裂解能、声子色散和 ab initio 分子动力学模拟，证实了单层隔离及其稳定性。室温下，ZrNI 和 HfNI 单层的晶格热导率分别为 7.8 W/(m⋅K) 和 11.7 W/(m⋅K)，大大低于典型的二维材料。由于 ZrNI 的高导电性，n 型掺杂 ZrNI 层的功率因数比 HfNI 单层高 9 倍。此外，无论温度如何，n 型 ZrNI 的最大功勋值始终高于 HfNI 单层。然而，与典型的二维材料相比，氮化锆和氮化铪层都显示出更优越的热电特性。这表明 n 型 ZrNI 单层是一种有利于热电应用的材料。

{"title":"Ternary transition-metal nitride halide monolayers MNI (M = Zr, Hf) with low thermal conductivity and high thermoelectric figure of merit","authors":"Radhakrishnan Anbarasan , Duckjong Kim , Jae Hyun Park","doi":"10.1016/j.commatsci.2024.113508","DOIUrl":"10.1016/j.commatsci.2024.113508","url":null,"abstract":"<div><div>Machine learning-based approaches are promising in pursuing the thermal properties of two-dimensional materials. Here, a comprehensive study of thermal transport and thermoelectric properties of the <span><math><mi>β</mi></math></span>-form of ZrNI and HfNI monolayers, a family of ternary transition-metal nitride halides (TMNH), is presented by employing machine learning-based interatomic potential, Boltzmann transport theory, and first-principles calculations. The monolayer isolation and its stability are confirmed via cleavage energies, phonon dispersions, and ab initio molecular dynamics simulations. At room temperature, the lattice thermal conductivity of the ZrNI and HfNI monolayers are 7.8 W/(m<span><math><mi>⋅</mi></math></span>K) and 11.7 W/(m<span><math><mi>⋅</mi></math></span>K), respectively, which are considerably lower than those of typical 2D materials. The power factor of n-type doped ZrNI layer is 9 times higher than the HfNI monolayer due to high electrical conductivity of ZrNI. Also, the maximum figure of merit values of the n-type ZrNI always appears higher than the HfNI monolayer regardless of temperature. However, both the ZrNI and HfNI layers show superior thermoelectric properties over typical 2D materials. It reveals that the n-type ZrNI monolayer is a beneficial material for thermoelectric applications.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"247 ","pages":"Article 113508"},"PeriodicalIF":3.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Density functional theory to decrypt metal-organic framework-A review 解密金属有机框架的密度泛函理论--综述

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

Computational Materials Science

Pub Date : 2024-11-16 DOI: 10.1016/j.commatsci.2024.113537

Shinta Davis, E. Athira, Vijisha K. Rajan

Metal-organic frameworks (MOFs), which are extremely crystalline but have molecular structures, exist at the interface between molecules and materials. The interwoven chemistry of MOFs allows for the construction of a virtually unlimited variety of materials, some of which can be employed in place of porous materials that have previously been used for many applications like gas storage, drug delivery, and so on. Due to the exponential development in the number of MOFs and their potential uses, it is impractical to test them for every prospective usage when novel MOFs are synthesised. Herein lies the significance of computational investigations. The major technique in computational investigations on metal–organic frameworks is the density-functional theory (DFT), which consistently yields atomic charges, electronic energies, molecular geometries, excited states vibrational analyses, NMR spectra, and so on. DFT can decipher the complete MOF clan. This review investigates MOFs and their electrical and optical properties, which can be employed in a variety of applications including catalysis, photoluminescence, absorption, separations, screening, and sensing of various materials utilising DFT and its tools.

金属有机框架（MOFs）具有极高的结晶性，但具有分子结构，存在于分子和材料之间的界面上。MOFs 相互交织的化学性质使其几乎可以制造出无限种类的材料，其中一些材料可以替代多孔材料，而多孔材料以前一直被用于气体储存、药物输送等许多应用领域。由于 MOFs 及其潜在用途的数量呈指数级增长，因此在合成新型 MOFs 时，对其每种潜在用途进行测试是不切实际的。计算研究的意义就在于此。对金属有机框架进行计算研究的主要技术是密度泛函理论（DFT），它能持续得出原子电荷、电子能量、分子几何形状、激发态振动分析、核磁共振光谱等结果。DFT 可以解密完整的 MOF 家族。本综述利用 DFT 及其工具研究 MOF 及其电学和光学特性，这些特性可用于催化、光致发光、吸收、分离、筛选和传感等多种应用领域。

{"title":"Density functional theory to decrypt metal-organic framework-A review","authors":"Shinta Davis, E. Athira, Vijisha K. Rajan","doi":"10.1016/j.commatsci.2024.113537","DOIUrl":"10.1016/j.commatsci.2024.113537","url":null,"abstract":"<div><div>Metal-organic frameworks (MOFs), which are extremely crystalline but have molecular structures, exist at the interface between molecules and materials. The interwoven chemistry of MOFs allows for the construction of a virtually unlimited variety of materials, some of which can be employed in place of porous materials that have previously been used for many applications like gas storage, drug delivery, and so on. Due to the exponential development in the number of MOFs and their potential uses, it is impractical to test them for every prospective usage when novel MOFs are synthesised. Herein lies the significance of computational investigations. The major technique in computational investigations on metal–organic frameworks is the density-functional theory (DFT), which consistently yields atomic charges, electronic energies, molecular geometries, excited states vibrational analyses, NMR spectra, and so on. DFT can decipher the complete MOF clan. This review investigates MOFs and their electrical and optical properties, which can be employed in a variety of applications including catalysis, photoluminescence, absorption, separations, screening, and sensing of various materials utilising DFT and its tools.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"247 ","pages":"Article 113537"},"PeriodicalIF":3.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142657001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

New structures of Rb2O and Cs2O stable at high pressures 在高压下稳定的 Rb2O 和 Cs2O 新结构

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

Computational Materials Science

Pub Date : 2024-11-16 DOI: 10.1016/j.commatsci.2024.113517

Anastassiya V. Mezentseva, Nursultan E. Sagatov, Pavel N. Gavryushkin, Dinara N. Sagatova

In this work, a search for stable structures of Rb

_{2}

O and Cs

_{2}

O was carried out using evolutionary algorithms within the density functional theory. In the studied pressure range of 0–100 GPa, for Rb

_{2}

O, the transitions

F m \bar{3} m

\leftrightarrow

P n m a

-I

\leftrightarrow

P n m a

-II were detected, which are realized at pressures of 2.6 and 40 GPa, respectively. For Cs

_{2}

O, the transitions

R \bar{3} m

\leftrightarrow

P n m a

-I

\leftrightarrow

I 4 / m m m

were revealed, which are realized at pressures of 6.3 and 63 GPa. As a result, previously unknown structures were found for these oxides Rb

_{2}

O-

P n m a

-II and Cs

_{2}

O-

I 4 / m m m

. According to the calculated phonon dispersion curves, the predicted structures are dynamically stable. Also, the P–T diagram for Rb

_{2}

O and Cs

_{2}

O was calculated for the first time. The electronic properties of the newly predicted high-pressure structures Rb

_{2}

O-

P n m a

-II and Cs

_{2}

O-

I 4 / m m m

were investigated, and the band structures and electron density of states (DOS) were calculated.

在这项研究中，我们利用密度泛函理论中的进化算法搜索了 Rb2O 和 Cs2O 的稳定结构。在所研究的 0-100 GPa 压力范围内，对于 Rb2O，检测到了 Fm3̄m ↔ Pnma-I ↔ Pnma-II 转变，这分别是在 2.6 和 40 GPa 压力下实现的。至于 Cs2O，则发现了 R3̄m ↔ Pnma-I ↔ I4/mmm 的转变，它们分别在 6.3 和 63 GPa 的压力下实现。因此，发现了这些氧化物 Rb2O-Pnma-II 和 Cs2O-I4/mmm 以前未知的结构。根据声子色散曲线的计算结果，所预测的结构具有动态稳定性。此外，还首次计算了 Rb2O 和 Cs2O 的 P-T 图。研究了新预测的高压结构 Rb2O-Pnma-II 和 Cs2O-I4/mmm 的电子特性，并计算了带状结构和电子态密度（DOS）。

引用次数: 0

Phase field numerical model for simulating the diffusion controlled stress corrosion cracking phenomena in anisotropic material 用于模拟各向异性材料中扩散控制应力腐蚀开裂现象的相场数值模型

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

Computational Materials Science

Pub Date : 2024-11-16 DOI: 10.1016/j.commatsci.2024.113528

Christian C Mathew , Jie Song , Emmanuel Adu-Gyamfi , Yao Fu

In this study, we develop a phase field numerical model to simulate diffusion-controlled stress corrosion cracking (SCC) in anisotropic materials. Our model is based on multiphysics model involving the electrochemical process, the mechanical response of the material, and the coupling between them. The corrosion system consists of a metallic solid phase immersed in an electrolyte, initially protected by a passive film. The model captures the breakdown of this film, leading to localized pitting corrosion, which subsequently evolves into stress corrosion cracking under the influence of mechanical stress. We employ the Allen-Cahn equation to describe the evolution of the non-conserved phase field variable, representing the metal-electrolyte interface, and the Cahn-Hilliard equation to account for the concentration field dynamics, ensuring volume conservation. The mechanical behavior of the anisotropic material is modeled using crystal plasticity, which accounts for the elastic and plastic deformation of the material, with the degradation due to corrosion incorporated into the stress–strain relationship. We analyze the transition from pitting to cracking in single crystalline, bi-crystalline, and polycrystalline structures. The results demonstrate the capability of the model to capture the complex interactions between electrochemical corrosion and mechanical deformation, providing insights into the pit-to-crack transition in anisotropic materials. The developed phase field numerical model presents a significant advancement in understanding and simulating SCC phenomena, with potential applications in various engineering fields where corrosion is a critical concern.

在本研究中，我们开发了一种相场数值模型，用于模拟各向异性材料中的扩散控制应力腐蚀开裂（SCC）。我们的模型基于多物理场模型，涉及电化学过程、材料的机械响应以及它们之间的耦合。腐蚀系统由浸入电解质中的金属固相组成，最初由一层被动薄膜保护。该模型捕捉了这层膜的破坏过程，从而导致局部点状腐蚀，随后在机械应力的影响下演变为应力腐蚀开裂。我们采用 Allen-Cahn 方程来描述代表金属-电解质界面的非守恒相场变量的演变，并采用 Cahn-Hilliard 方程来解释浓度场动态，以确保体积守恒。各向异性材料的机械行为使用晶体塑性来建模，该模型考虑了材料的弹性和塑性变形，并将腐蚀引起的降解纳入应力应变关系中。我们分析了单晶、双晶和多晶结构中从点蚀到开裂的转变过程。结果表明，该模型有能力捕捉电化学腐蚀与机械变形之间复杂的相互作用，为各向异性材料从点蚀到开裂的转变提供了深入见解。所开发的相场数值模型在理解和模拟 SCC 现象方面取得了重大进展，有望应用于腐蚀问题严重的各个工程领域。

{"title":"Phase field numerical model for simulating the diffusion controlled stress corrosion cracking phenomena in anisotropic material","authors":"Christian C Mathew , Jie Song , Emmanuel Adu-Gyamfi , Yao Fu","doi":"10.1016/j.commatsci.2024.113528","DOIUrl":"10.1016/j.commatsci.2024.113528","url":null,"abstract":"<div><div>In this study, we develop a phase field numerical model to simulate diffusion-controlled stress corrosion cracking (SCC) in anisotropic materials. Our model is based on multiphysics model involving the electrochemical process, the mechanical response of the material, and the coupling between them. The corrosion system consists of a metallic solid phase immersed in an electrolyte, initially protected by a passive film. The model captures the breakdown of this film, leading to localized pitting corrosion, which subsequently evolves into stress corrosion cracking under the influence of mechanical stress. We employ the Allen-Cahn equation to describe the evolution of the non-conserved phase field variable, representing the metal-electrolyte interface, and the Cahn-Hilliard equation to account for the concentration field dynamics, ensuring volume conservation. The mechanical behavior of the anisotropic material is modeled using crystal plasticity, which accounts for the elastic and plastic deformation of the material, with the degradation due to corrosion incorporated into the stress–strain relationship. We analyze the transition from pitting to cracking in single crystalline, bi-crystalline, and polycrystalline structures. The results demonstrate the capability of the model to capture the complex interactions between electrochemical corrosion and mechanical deformation, providing insights into the pit-to-crack transition in anisotropic materials. The developed phase field numerical model presents a significant advancement in understanding and simulating SCC phenomena, with potential applications in various engineering fields where corrosion is a critical concern.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"247 ","pages":"Article 113528"},"PeriodicalIF":3.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Crystal plasticity study on deformation behavior of dual-phase Ti alloy under biaxial loading conditions 双轴加载条件下双相钛合金变形行为的晶体塑性研究

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

Computational Materials Science

Pub Date : 2024-11-16 DOI: 10.1016/j.commatsci.2024.113515

Zixiang Liu , Tong Zhao , Xuexiong Li , Jinhu Zhang , Dongsheng Xu , Rui Yang

Titanium alloys are widely used because of their excellent mechanical properties, but the complex service environment requires a profound understanding of their deformation mechanism and mechanical behavior. The study of biaxial mechanical behavior has been plagued for decades by the inconvenience of experiments and the difficulty of ensuring the accuracy. To get a further understanding of the micromechanical behavior and corresponding deformation mechanisms of duplex titanium alloys under multiaxial loading, crystal plasticity modeling with a spectrum solver was employed in this work. The results were simultaneously analyzed using post-processing and other visualization methods to explore the disparity in deformation mechanisms between uniaxial and biaxial loading scenarios. The uniaxial tensile mechanical response of CP-Ti and Ti64 alloy were well captured using crystal plasticity modeling compared to experimental results, demonstrating both the reliability of the established model and constitutive parameters used. A strengthening effect under biaxial loading occurred owing to unique structural characteristics and mechanical constraints associated with tensile direction of hexagonal crystal structure. The region of strain bands that emerges following an increase in the biaxial ratio indicates that unbalanced biaxial stress loading can cause fracture. Prismatic slip along with basal slip predominantly governs deformation process of Ti64 alloy, while {

10 \bar{1} 2

} tensile twinning facilitates plastic deformation when there is limited availability of slip systems. These conclusions, on one hand, demonstrate the high-fidelity characteristic of simulation techniques and, on the other, enhance the understanding of the mechanical responses and damage mechanisms in complex service environments.

钛合金因其优异的机械性能而被广泛应用，但复杂的使用环境要求对其变形机理和机械行为有深刻的了解。几十年来，双轴力学行为的研究一直受到实验不便、精度难以保证等问题的困扰。为了进一步了解双相钛合金在多轴载荷作用下的微观力学行为和相应的变形机制，本研究采用频谱求解器建立晶体塑性模型。同时使用后处理和其他可视化方法对结果进行分析，以探索单轴和双轴加载情况下变形机制的差异。与实验结果相比，晶体塑性模型很好地捕捉到了 CP-Ti 和 Ti64 合金的单轴拉伸机械响应，证明了所建立模型和所使用构成参数的可靠性。由于六方晶体结构独特的结构特征以及与拉伸方向相关的机械约束，在双轴载荷作用下产生了强化效应。双轴比增加后出现的应变带区域表明，不平衡的双轴应力加载可导致断裂。棱柱滑移和基底滑移主要控制着 Ti64 合金的变形过程，而{101¯2}拉伸孪晶则在滑移系统有限的情况下促进塑性变形。这些结论一方面证明了模拟技术的高保真特性，另一方面也加深了人们对复杂服役环境下的机械响应和损伤机制的理解。

{"title":"Crystal plasticity study on deformation behavior of dual-phase Ti alloy under biaxial loading conditions","authors":"Zixiang Liu , Tong Zhao , Xuexiong Li , Jinhu Zhang , Dongsheng Xu , Rui Yang","doi":"10.1016/j.commatsci.2024.113515","DOIUrl":"10.1016/j.commatsci.2024.113515","url":null,"abstract":"<div><div>Titanium alloys are widely used because of their excellent mechanical properties, but the complex service environment requires a profound understanding of their deformation mechanism and mechanical behavior. The study of biaxial mechanical behavior has been plagued for decades by the inconvenience of experiments and the difficulty of ensuring the accuracy. To get a further understanding of the micromechanical behavior and corresponding deformation mechanisms of duplex titanium alloys under multiaxial loading, crystal plasticity modeling with a spectrum solver was employed in this work. The results were simultaneously analyzed using post-processing and other visualization methods to explore the disparity in deformation mechanisms between uniaxial and biaxial loading scenarios. The uniaxial tensile mechanical response of CP-Ti and Ti64 alloy were well captured using crystal plasticity modeling compared to experimental results, demonstrating both the reliability of the established model and constitutive parameters used. A strengthening effect under biaxial loading occurred owing to unique structural characteristics and mechanical constraints associated with tensile direction of hexagonal crystal structure. The region of strain bands that emerges following an increase in the biaxial ratio indicates that unbalanced biaxial stress loading can cause fracture. Prismatic slip along with basal slip predominantly governs deformation process of Ti64 alloy, while {<span><math><mrow><mn>10</mn><mover><mn>1</mn><mo>¯</mo></mover><mn>2</mn></mrow></math></span>} tensile twinning facilitates plastic deformation when there is limited availability of slip systems. These conclusions, on one hand, demonstrate the high-fidelity characteristic of simulation techniques and, on the other, enhance the understanding of the mechanical responses and damage mechanisms in complex service environments.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"247 ","pages":"Article 113515"},"PeriodicalIF":3.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142657000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Engineering the optoelectronic properties of ZnS (1100) surface using selected 3d transition metal dopants for enhanced Photoelectrochemical water Splitting: A DFT study 利用选定的三维过渡金属掺杂剂对 ZnS (1100) 表面的光电特性进行工程化处理，以增强光电化学分水能力：DFT 研究

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

Computational Materials Science

Pub Date : 2024-11-16 DOI: 10.1016/j.commatsci.2024.113540

J.J. Kiptarus , K.K. Korir , D.N. Githinji , H.K. Kiriamiti

ZnS (1100) surface has emerged as a promising photocatalyst for water split- ting due to its rapid generation of electron-hole pairs upon photoexcitation and high hydrogen evolution efficiency. However, its widespread use has been limited by its response to UV spectrum and rapid recombination of charge carriers. Studies have shown that doping ZnS with transition metals can modify its band gap edge and alter its optical properties. Despite this, there are few comprehensive studies that have systematically explore the potential of doped ZnS (1100) surface for Photo-electrochemical (PEC) applications. In this work, the effects of selected transition metal (TM) dopants (Mn, Cu, Co and Fe) on the optoelectronic properties of ZnS (1100) surface using density functional theory approach has been explored. The results showed that the stability of TM dopants in ZnS (1100) surface is dependent on the d character of the TM dopant as well as their concentration and doping site. Further, it was noted that Zn-rich synthesis conditions were favorable for introduction of TM dopants compared to S-rich conditions. Notably, among the dopants studied, Cu exhibited the highest stability, whereas Co, Mn and Fe displayed decreasing levels of stability. Mn and Fe (for dopant concentration between 1–6%) induces reduction of band-gap energy by 15–60% and 19–51%, respectively, while Cu and Co dopants of similar concentrations induced a more dramatic reduction of band gap energy between 37–78% and 26–75%, respectively. Additionally, band-edge alignment analysis showed that ZnS (1100) surface doped with 4% Cu and 2% Co falls below the redox potential of water (H⁺/H₂). Therefore, Cu and Co are anticipated to induce significant blue shift and offer improved PEC activity.

由于 ZnS（1100）表面在光激发时能迅速产生电子-空穴对，且氢气进化效率高，因此已成为一种很有前途的分水光催化剂。然而，由于其对紫外光谱的反应和电荷载流子的快速重组，其广泛应用受到了限制。研究表明，在 ZnS 中掺杂过渡金属可以改变其带隙边并改变其光学特性。尽管如此，系统地探索掺杂 ZnS（1100）表面在光电化学（PEC）应用中的潜力的综合研究还很少。本研究采用密度泛函理论方法，探讨了特定过渡金属（TM）掺杂剂（锰、铜、钴和铁）对 ZnS（1100）表面光电特性的影响。结果表明，钛金属掺杂剂在 ZnS（1100）表面的稳定性取决于钛金属掺杂剂的 d 特性及其浓度和掺杂位点。此外，与富含 S 的条件相比，富含 Zn 的合成条件更有利于引入 TM 掺杂剂。值得注意的是，在所研究的掺杂剂中，铜的稳定性最高，而钴、锰和铁的稳定性则依次降低。锰和铁（掺杂浓度在 1-6% 之间）导致带隙能分别降低了 15-60% 和 19-51%，而类似浓度的铜和钴掺杂则导致带隙能更大幅度地降低，分别降低了 37-78% 和 26-75%。此外，带边排列分析表明，掺杂了 4% Cu 和 2% Co 的 ZnS（1100）表面低于水的氧化还原电位（H+/H2）。因此，预计铜和钴会诱发显著的蓝移，并提高 PEC 活性。

{"title":"Engineering the optoelectronic properties of ZnS (1100) surface using selected 3d transition metal dopants for enhanced Photoelectrochemical water Splitting: A DFT study","authors":"J.J. Kiptarus , K.K. Korir , D.N. Githinji , H.K. Kiriamiti","doi":"10.1016/j.commatsci.2024.113540","DOIUrl":"10.1016/j.commatsci.2024.113540","url":null,"abstract":"<div><div>ZnS (1100) surface has emerged as a promising photocatalyst for water split- ting due to its rapid generation of electron-hole pairs upon photoexcitation and high hydrogen evolution efficiency. However, its widespread use has been limited by its response to UV spectrum and rapid recombination of charge carriers. Studies have shown that doping ZnS with transition metals can modify its band gap edge and alter its optical properties. Despite this, there are few comprehensive studies that have systematically explore the potential of doped ZnS (1100) surface for Photo-electrochemical (PEC) applications. In this work, the effects of selected transition metal (TM) dopants (Mn, Cu, Co and Fe) on the optoelectronic properties of ZnS (1100) surface using density functional theory approach has been explored. The results showed that the stability of TM dopants in ZnS (1100) surface is dependent on the <em>d</em> character of the TM dopant as well as their concentration and doping site. Further, it was noted that Zn-rich synthesis conditions were favorable for introduction of TM dopants compared to S-rich conditions. Notably, among the dopants studied, Cu exhibited the highest stability, whereas Co, Mn and Fe displayed decreasing levels of stability. Mn and Fe (for dopant concentration between 1–6%) induces reduction of band-gap energy by 15–60% and 19–51%, respectively, while Cu and Co dopants of similar concentrations induced a more dramatic reduction of band gap energy between 37–78% and 26–75%, respectively. Additionally, band-edge alignment analysis showed that ZnS (1100) surface doped with 4% Cu and 2% Co falls below the redox potential of water (H<sup>+</sup>/H<sub>2</sub>). Therefore, Cu and Co are anticipated to induce significant blue shift and offer improved PEC activity.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"247 ","pages":"Article 113540"},"PeriodicalIF":3.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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

Data-driven 2D grain growth microstructure prediction using deep learning and spectral graph theory 利用深度学习和谱图理论进行数据驱动的二维晶粒生长微观结构预测

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

Computational Materials Science

Pub Date : 2024-11-15 DOI: 10.1016/j.commatsci.2024.113504

José Niño, Oliver K. Johnson

In this paper, we present an alternative method to grain growth simulations. Traditional grain growth algorithms can be computationally expensive, especially when considering anisotropic grain boundary (GB) properties. The new Semi-Stochastic Grain Growth Prediction (SSGGP) model consists of two main components: a statistical evolution model that predicts the evolution of the GB network spectrum and a conditional diffusion model that generates grain growth morphologies at different time steps. These models are trained on a dataset Niño and Johnson (2024) that contains thousands of microstructures obtained from anisotropic grain growth simulations. We test the effectiveness of our model by comparing microstructure statistics (e.g., grain size distribution, orientation distribution function (ODF), misorientation distribution function (MDF), and GB energy distribution) with those obtained from grain growth simulations. The results indicate that the SSGGP model shows good agreement in terms of these statistics. Moreover, once trained, the SSGGP is almost ten times faster in obtaining the evolved state of a microstructure. We also find evidence for self-similarity of the GB network during steady-state normal anisotropic grain growth.

在本文中，我们提出了一种晶粒生长模拟的替代方法。传统的晶粒生长算法计算成本高昂，尤其是在考虑各向异性的晶界（GB）特性时。新的半随机晶粒生长预测（SSGGP）模型由两个主要部分组成：一个是预测 GB 网络谱演变的统计演变模型，另一个是在不同时间步骤生成晶粒生长形态的条件扩散模型。这些模型是在 Niño 和 Johnson（2024 年）的数据集上训练的，该数据集包含数千个从各向异性晶粒生长模拟中获得的微观结构。我们通过比较微结构统计数据（如晶粒尺寸分布、取向分布函数（ODF）、错取向分布函数（MDF）和 GB 能量分布）与晶粒生长模拟获得的数据，检验了模型的有效性。结果表明，SSGGP 模型在这些统计数据方面显示出良好的一致性。此外，一旦经过训练，SSGGP 在获取微结构演化状态方面的速度几乎快十倍。我们还发现了稳态正常各向异性晶粒生长过程中 GB 网络自相似性的证据。

{"title":"Data-driven 2D grain growth microstructure prediction using deep learning and spectral graph theory","authors":"José Niño, Oliver K. Johnson","doi":"10.1016/j.commatsci.2024.113504","DOIUrl":"10.1016/j.commatsci.2024.113504","url":null,"abstract":"<div><div>In this paper, we present an alternative method to grain growth simulations. Traditional grain growth algorithms can be computationally expensive, especially when considering anisotropic grain boundary (GB) properties. The new Semi-Stochastic Grain Growth Prediction (SSGGP) model consists of two main components: a statistical evolution model that predicts the evolution of the GB network spectrum and a conditional diffusion model that generates grain growth morphologies at different time steps. These models are trained on a dataset Niño and Johnson (2024) that contains thousands of microstructures obtained from anisotropic grain growth simulations. We test the effectiveness of our model by comparing microstructure statistics (e.g., grain size distribution, orientation distribution function (ODF), misorientation distribution function (MDF), and GB energy distribution) with those obtained from grain growth simulations. The results indicate that the SSGGP model shows good agreement in terms of these statistics. Moreover, once trained, the SSGGP is almost ten times faster in obtaining the evolved state of a microstructure. We also find evidence for self-similarity of the GB network during steady-state normal anisotropic grain growth.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"247 ","pages":"Article 113504"},"PeriodicalIF":3.1,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142656998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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