Pub Date : 2024-05-12DOI: 10.1088/1361-651x/ad461e
Yixiu Luo, Juan Wang, Luchao Sun and Jingyang Wang
Understanding the phononic origin of the infrared (IR) dielectric properties of yttria (Y2O3) and other rare-earth sesquioxides (RE2O3) is a fundamental task in the search of appropriate RE2O3 materials that serve particular IR optical applications. We herein investigate the IR dielectric properties of RE2O3 (RE = Y, Gd, Ho, Lu) using density functional theory-based phonon calculations and Lorentz oscillator model. The abundant IR-active optical phonon modes that are available for effective absorption of photons result in high reflectance of RE2O3, among which four IR-active modes originated from large distortions of REO6 octahedra are found to contribute dominantly to the phonon dielectric constants. Particularly, the present calculation method by considering one-phonon absorption process is demonstrated with good reliability in predicting the IR dielectric parameters of RE2O3 at the far-IR as well as the vicinity of mid-IR region, and the potential cutoff frequency/wavelength of its applicability is disclosed as characterized by the maximum frequency of IR-active longitudinal phonon modes. The results deepen the understanding on IR dielectric properties of RE2O3, and aid the computational design of materials with appropriate IR properties.
{"title":"Phononic origin of the infrared dielectric properties of RE2O3 (RE = Y, Gd, Ho, Lu) compounds","authors":"Yixiu Luo, Juan Wang, Luchao Sun and Jingyang Wang","doi":"10.1088/1361-651x/ad461e","DOIUrl":"https://doi.org/10.1088/1361-651x/ad461e","url":null,"abstract":"Understanding the phononic origin of the infrared (IR) dielectric properties of yttria (Y2O3) and other rare-earth sesquioxides (RE2O3) is a fundamental task in the search of appropriate RE2O3 materials that serve particular IR optical applications. We herein investigate the IR dielectric properties of RE2O3 (RE = Y, Gd, Ho, Lu) using density functional theory-based phonon calculations and Lorentz oscillator model. The abundant IR-active optical phonon modes that are available for effective absorption of photons result in high reflectance of RE2O3, among which four IR-active modes originated from large distortions of REO6 octahedra are found to contribute dominantly to the phonon dielectric constants. Particularly, the present calculation method by considering one-phonon absorption process is demonstrated with good reliability in predicting the IR dielectric parameters of RE2O3 at the far-IR as well as the vicinity of mid-IR region, and the potential cutoff frequency/wavelength of its applicability is disclosed as characterized by the maximum frequency of IR-active longitudinal phonon modes. The results deepen the understanding on IR dielectric properties of RE2O3, and aid the computational design of materials with appropriate IR properties.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140931274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-10DOI: 10.1088/1361-651x/ad44bd
Eric Abercrombie, J Gregory McDaniel
The current approach to modeling viscoelastic materials in most commercial finite element packages is based on the General Maxwell Model, which views these materials as combinations of spring and dashpot elements. However, the data can be incorporated more directly into a transient finite element study by direct interpolation of the relaxation function. This work explores a linear interpolation scheme to the inclusion of viscoelastic relaxation functions on an example problem. The results show several benefits over the General Maxwell Model for transient studies. Included in the analysis are displacement solutions utilizing both approaches, relaxation function error calculations for both approaches, and parametric runtime studies comparing speed of calculation. The variation in computational flop counts is considered and an argument is made for the preference of the proposed approach.
{"title":"Direct integration of measured viscoelastic relaxation data in time-domain finite element simulations","authors":"Eric Abercrombie, J Gregory McDaniel","doi":"10.1088/1361-651x/ad44bd","DOIUrl":"https://doi.org/10.1088/1361-651x/ad44bd","url":null,"abstract":"The current approach to modeling viscoelastic materials in most commercial finite element packages is based on the General Maxwell Model, which views these materials as combinations of spring and dashpot elements. However, the data can be incorporated more directly into a transient finite element study by direct interpolation of the relaxation function. This work explores a linear interpolation scheme to the inclusion of viscoelastic relaxation functions on an example problem. The results show several benefits over the General Maxwell Model for transient studies. Included in the analysis are displacement solutions utilizing both approaches, relaxation function error calculations for both approaches, and parametric runtime studies comparing speed of calculation. The variation in computational flop counts is considered and an argument is made for the preference of the proposed approach.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140931188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-09DOI: 10.1088/1361-651x/ad4408
George Petsos
We examine the influence of grains size on the stability of polycrystalline coherent binary solid solutions. By assuming that the grains are isotropic, we find that the tendency for instability decreases as the radius of the grains decrease. We also find that a temperature-dependent critical grain radius exists below which the tendency for instability vanishes and the grains are stable, with respect to infinitesimal composition fluctuations, for any initial composition. We find that the critical grain radius decreases monotonically as the temperature decrease. If the radius of the grains is smaller than the minimum critical grain radius the grains are stable for any temperature and initial composition.
{"title":"Size effects on spinodal decomposition","authors":"George Petsos","doi":"10.1088/1361-651x/ad4408","DOIUrl":"https://doi.org/10.1088/1361-651x/ad4408","url":null,"abstract":"We examine the influence of grains size on the stability of polycrystalline coherent binary solid solutions. By assuming that the grains are isotropic, we find that the tendency for instability decreases as the radius of the grains decrease. We also find that a temperature-dependent critical grain radius exists below which the tendency for instability vanishes and the grains are stable, with respect to infinitesimal composition fluctuations, for any initial composition. We find that the critical grain radius decreases monotonically as the temperature decrease. If the radius of the grains is smaller than the minimum critical grain radius the grains are stable for any temperature and initial composition.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140931079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-09DOI: 10.1088/1361-651x/ad4407
Rahul Ghosh, Bhavana Sahu, Arjun Dey, Hari Krishna Thota, Karabi Das
Nowadays, anodic coating on additively manufactured (AM) or 3D printed Al–10Si–Mg alloy are used for various components in spacecraft such as antenna feeds, wave guides, structural brackets, collimators, thermal radiators etc. In this study, artificial neural network (ANN) and power law-based models are developed from experimental nanoindentation data for predicting elastic modulus and hardness of anodized AM Al–10Si–Mg at any desired loads. Data from nanoindentation experiments conducted on plan- and cross-sections of anodized coating on AM Al–10Si–Mg alloy was considered for modeling. Apart from nanomechanical properties, load and displacement curves were predicted using Python software from ANN and the Power law model of nanoindentation. It is observed that the ANN model of 50 mN nanoindentation experimental data can accurately predict the loading pattern at any desired load below 50 mN. Elastic modulus and hardness of anodized AM Al–10Si–Mg computed from ANN and the power law model of the unloading curve are also comparable with the values obtained from Weibull distribution analysis reported elsewhere. The derived models were also used to predict nanomechanical properties at 25 and 35 mN, for which no experimental data was available. The computed hardness of plan section of the anodic coating is 3.99 and 4.02 GPa for 25 and 35 mN, respectively. The computed hardness of cross-section of the anodic coating of is 7.16 and 6.61 GPa for 25 and 35 mN, respectively. Thus, the ANN and Power law model of nanoindentation can predict elastic modulus and hardness at different loads by conducting the minimum number of experiments. The novel approach to predict nanomechanical properties using ANN resulted in determining realistic and design specific data on hardness and modulus of the anodized coating on AM Al–10Si–Mg alloy.
如今，阳极涂层添加剂制造（AM）或三维打印的 Al-10Si-Mg 合金被用于航天器中的各种部件，如天线馈线、波导、结构支架、准直器、热辐射器等。本研究根据纳米压痕实验数据开发了基于人工神经网络（ANN）和幂律的模型，用于预测阳极氧化 AM Al-10Si-Mg 在任何所需载荷下的弹性模量和硬度。建模时考虑了对 AM Al-10Si-Mg 合金阳极氧化涂层的平面和横截面进行的纳米压痕实验数据。除纳米力学性能外，还使用 Python 软件根据 ANN 和纳米压痕幂律模型预测了载荷和位移曲线。据观察，50 毫牛顿纳米压痕实验数据的 ANN 模型可以准确预测 50 毫牛顿以下任何所需载荷的加载模式。根据 ANN 和卸载曲线的幂律模型计算出的阳极氧化 AM Al-10Si-Mg 的弹性模量和硬度值也与其他地方报道的通过 Weibull 分布分析获得的值相当。推导出的模型还用于预测 25 和 35 mN 条件下的纳米力学性能，因为没有这方面的实验数据。阳极涂层平面部分的计算硬度在 25 和 35 毫牛顿时分别为 3.99 和 4.02 GPa。阳极涂层横截面的计算硬度在 25 和 35 mN 条件下分别为 7.16 和 6.61 GPa。因此，纳米压痕的 ANN 和幂律模型可以通过进行最少的实验来预测不同载荷下的弹性模量和硬度。利用 ANN 预测纳米力学性能的新方法确定了 AM Al-10Si-Mg 合金阳极氧化涂层硬度和模量的现实和设计特定数据。
{"title":"Artificial neural network-based approach for prediction of nanomechanical properties of anodic coating on additively manufactured Al–10Si–Mg alloy","authors":"Rahul Ghosh, Bhavana Sahu, Arjun Dey, Hari Krishna Thota, Karabi Das","doi":"10.1088/1361-651x/ad4407","DOIUrl":"https://doi.org/10.1088/1361-651x/ad4407","url":null,"abstract":"Nowadays, anodic coating on additively manufactured (AM) or 3D printed Al–10Si–Mg alloy are used for various components in spacecraft such as antenna feeds, wave guides, structural brackets, collimators, thermal radiators etc. In this study, artificial neural network (ANN) and power law-based models are developed from experimental nanoindentation data for predicting elastic modulus and hardness of anodized AM Al–10Si–Mg at any desired loads. Data from nanoindentation experiments conducted on plan- and cross-sections of anodized coating on AM Al–10Si–Mg alloy was considered for modeling. Apart from nanomechanical properties, load and displacement curves were predicted using Python software from ANN and the Power law model of nanoindentation. It is observed that the ANN model of 50 mN nanoindentation experimental data can accurately predict the loading pattern at any desired load below 50 mN. Elastic modulus and hardness of anodized AM Al–10Si–Mg computed from ANN and the power law model of the unloading curve are also comparable with the values obtained from Weibull distribution analysis reported elsewhere. The derived models were also used to predict nanomechanical properties at 25 and 35 mN, for which no experimental data was available. The computed hardness of plan section of the anodic coating is 3.99 and 4.02 GPa for 25 and 35 mN, respectively. The computed hardness of cross-section of the anodic coating of is 7.16 and 6.61 GPa for 25 and 35 mN, respectively. Thus, the ANN and Power law model of nanoindentation can predict elastic modulus and hardness at different loads by conducting the minimum number of experiments. The novel approach to predict nanomechanical properties using ANN resulted in determining realistic and design specific data on hardness and modulus of the anodized coating on AM Al–10Si–Mg alloy.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This reply is addressed to comments on our paper entitled ‘Composition-based Aluminum Alloy Selection Using an Artificial Neural Network.’ There are six main comments, and we addressed the comments carefully. This machine learning (ML) modeling is only part of the development of a broader material selection (or material screening) system. Consideration of other material properties can certainly be included through the integration of ML systems.
本答复是针对我们题为《使用人工神经网络进行基于成分的铝合金选择》的论文所提出的意见。主要有六条意见，我们已认真处理了这些意见。这种机器学习（ML）建模只是开发更广泛的材料选择（或材料筛选）系统的一部分。通过集成 ML 系统，当然还可以考虑其他材料特性。
{"title":"Reply to comment on ‘Composition-based aluminum alloy selection using an artificial neural network’","authors":"Jaka Fajar Fatriansyah, Raihan Kenji Rizqillah, Iping Suhariadi, Andreas Federico, Ade Kurniawan","doi":"10.1088/1361-651x/ad4574","DOIUrl":"https://doi.org/10.1088/1361-651x/ad4574","url":null,"abstract":"This reply is addressed to comments on our paper entitled ‘Composition-based Aluminum Alloy Selection Using an Artificial Neural Network.’ There are six main comments, and we addressed the comments carefully. This machine learning (ML) modeling is only part of the development of a broader material selection (or material screening) system. Consideration of other material properties can certainly be included through the integration of ML systems.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140931107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-08DOI: 10.1088/1361-651x/ad4573
Russell Wanhill
This article comments on the article ‘Composition-based aluminum alloy selection using an artificial neural network previously published in this journal. It is shown that the input information of the modelling is much too limited and the selection procedure is simplistic and not applicable or relevant to the actual selection procedures for aerospace aluminum alloys. The modelling has been done without sufficient engineering knowledge (almost none) about the properties, selection criteria, alloy compositions and processing of aerospace structural aluminum alloys.
{"title":"Comment on ‘Composition-based aluminum alloy selection using an artificial neural network’","authors":"Russell Wanhill","doi":"10.1088/1361-651x/ad4573","DOIUrl":"https://doi.org/10.1088/1361-651x/ad4573","url":null,"abstract":"This article comments on the article ‘Composition-based aluminum alloy selection using an artificial neural network previously published in this journal. It is shown that the input information of the modelling is much too limited and the selection procedure is simplistic and not applicable or relevant to the actual selection procedures for aerospace aluminum alloys. The modelling has been done without sufficient engineering knowledge (almost none) about the properties, selection criteria, alloy compositions and processing of aerospace structural aluminum alloys.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-08DOI: 10.1088/1361-651x/ad42bb
Lucas Benoit-Maréchal, Marco Salvalaglio
The Swift–Hohenberg (SH) and phase-field crystal (PFC) models are minimal yet powerful approaches for studying phenomena such as pattern formation, collective order, and defects via smooth order parameters. They are based on a free-energy functional that inherently includes elasticity effects. This study addresses how gradient elasticity (GE), a theory that accounts for elasticity effects at microscopic scales by introducing additional characteristic lengths, is incorporated into SH and PFC models. After presenting the fundamentals of these theories and models, we first calculate the characteristic lengths for various lattice symmetries in an approximated setting. We then discuss numerical simulations of stress fields at dislocations and comparisons with analytic solutions within first and second strain-gradient elasticity. Effective GE characteristic lengths for the elastic fields induced by dislocations are found to depend on the free-energy parameters in the same manner as the phase correlation length, thus unveiling how they change with the quenching depth. The findings presented in this study enable a thorough discussion and analysis of small-scale elasticity effects in pattern formation and crystalline systems using SH and PFC models and, importantly, complete the elasticity analysis therein. Additionally, we provide a microscopic foundation for GE in the context of order-disorder phase transitions.
斯威夫特-霍恩伯格（SH）模型和相场晶体（PFC）模型是研究图案形成、集体有序和通过平滑有序参数产生缺陷等现象的最简便而又强大的方法。它们以自由能函数为基础，其中固有地包含了弹性效应。梯度弹性（GE）理论通过引入额外的特征长度来解释微观尺度上的弹性效应，本研究探讨了如何将梯度弹性纳入 SH 和 PFC 模型。在介绍了这些理论和模型的基本原理后，我们首先计算了各种晶格对称性的近似特征长度。然后，我们讨论了位错应力场的数值模拟以及与第一和第二应变梯度弹性分析解的比较。我们发现，位错诱导的弹性场的有效 GE 特性长度与相相关长度一样取决于自由能参数，从而揭示了它们如何随淬火深度而变化。本研究中的发现使我们能够利用 SH 和 PFC 模型对图案形成和晶体系统中的小尺度弹性效应进行全面的讨论和分析，重要的是完成了其中的弹性分析。此外，我们还为有序-无序相变背景下的 GE 提供了微观基础。
{"title":"Gradient elasticity in Swift–Hohenberg and phase-field crystal models","authors":"Lucas Benoit-Maréchal, Marco Salvalaglio","doi":"10.1088/1361-651x/ad42bb","DOIUrl":"https://doi.org/10.1088/1361-651x/ad42bb","url":null,"abstract":"The Swift–Hohenberg (SH) and phase-field crystal (PFC) models are minimal yet powerful approaches for studying phenomena such as pattern formation, collective order, and defects via smooth order parameters. They are based on a free-energy functional that inherently includes elasticity effects. This study addresses how gradient elasticity (GE), a theory that accounts for elasticity effects at microscopic scales by introducing additional characteristic lengths, is incorporated into SH and PFC models. After presenting the fundamentals of these theories and models, we first calculate the characteristic lengths for various lattice symmetries in an approximated setting. We then discuss numerical simulations of stress fields at dislocations and comparisons with analytic solutions within first and second strain-gradient elasticity. Effective GE characteristic lengths for the elastic fields induced by dislocations are found to depend on the free-energy parameters in the same manner as the phase correlation length, thus unveiling how they change with the quenching depth. The findings presented in this study enable a thorough discussion and analysis of small-scale elasticity effects in pattern formation and crystalline systems using SH and PFC models and, importantly, complete the elasticity analysis therein. Additionally, we provide a microscopic foundation for GE in the context of order-disorder phase transitions.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-25DOI: 10.1088/1361-651x/ad437c
Noya Dimanstein Firman, E. Engelberg, Y. Ashkenazy
A method for identifying dislocation motion in atomistic simulations is presented. While identifying static and moving dislocations within a single crystal or a combination of such is well established, the method described here is tailored to identify dislocation motion by correlating the displacements of individual atoms. This facilitates the identification of dislocation motion in complex structural arrangements, and allows the specific contribution to plastic deformation, due to dislocation motion, to be separated from that of other mechanisms. The method is applied to test cases in crystals and grain boundaries, in which irradiation-induced creep was induced. It is shown that the method singles out the moving dislocations from among the dislocation forest at grain boundaries, thus identifying the specific reactions driving the distortion at any given time. This enables the study of dislocation processes in the presence of realistic obstacles, and the study of the effects of microstructure on dislocation mobility. As an example of such a study, the method is applied to rule out intragranular slip, and to estimate the contribution of dislocation motion to strain, in a NC undergoing irradiation-induced creep.
{"title":"Detection of dislocation motion in atomistic simulations of nanocrystalline materials","authors":"Noya Dimanstein Firman, E. Engelberg, Y. Ashkenazy","doi":"10.1088/1361-651x/ad437c","DOIUrl":"https://doi.org/10.1088/1361-651x/ad437c","url":null,"abstract":"\u0000 A method for identifying dislocation motion in atomistic simulations is presented. While identifying static and moving dislocations within a single crystal or a combination of such is well established, the method described here is tailored to identify dislocation motion by correlating the displacements of individual atoms. This facilitates the identification of dislocation motion in complex structural arrangements, and allows the specific contribution to plastic deformation, due to dislocation motion, to be separated from that of other mechanisms. The method is applied to test cases in crystals and grain boundaries, in which irradiation-induced creep was induced. It is shown that the method singles out the moving dislocations from among the dislocation forest at grain boundaries, thus identifying the specific reactions driving the distortion at any given time. This enables the study of dislocation processes in the presence of realistic obstacles, and the study of the effects of microstructure on dislocation mobility. As an example of such a study, the method is applied to rule out intragranular slip, and to estimate the contribution of dislocation motion to strain, in a NC undergoing irradiation-induced creep.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140656826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-24DOI: 10.1088/1361-651x/ad42bc
Brij Kumar Bareth, M. N. Tripathi
The lead-free double-perovskite halide materials are promising materials for photovoltaics. Recently, Cs2AgInBr6 (CAIB) has been synthesized with the estimated direct nature of a band gap value of 1.57 eV. To cover the wide solar spectrum for photo-conversion, the applied strain is one of the promising approaches to achieve it through band gap tuning. The density functional theory (DFT) is used to investigate the effect of compressive strain on the structural, electronic, and optical properties of CAIB. The elastic constants follow the Born-Huang stability criterion and show the mechanical stability of the composition even under compressive strain. The Poisson's ratio in the range of 0.23 to 0.26 and B/G >1.75 indicate the ductile and soft nature of the material. The band gap increases monotonically without changing the direct nature of the band gap by increasing the compressive strain. However, the larger value of strain reproduces more dispersive conduction band minima and valence band maxima, resulting in lower effective masses and consequently larger carrier mobilities. The variations in the optical properties of CAIB are explored under compressive strain. The structural, electronic, and good photoresponse of the material in the visible and ultraviolet regions indicate the suitability of the material for flexible photovoltaics.
{"title":"First-principles study of the effect of strain on the structural and optoelectronic properties of flexible photovoltaic material Cs2AgInBr6","authors":"Brij Kumar Bareth, M. N. Tripathi","doi":"10.1088/1361-651x/ad42bc","DOIUrl":"https://doi.org/10.1088/1361-651x/ad42bc","url":null,"abstract":"\u0000 The lead-free double-perovskite halide materials are promising materials for photovoltaics. Recently, Cs2AgInBr6 (CAIB) has been synthesized with the estimated direct nature of a band gap value of 1.57 eV. To cover the wide solar spectrum for photo-conversion, the applied strain is one of the promising approaches to achieve it through band gap tuning. The density functional theory (DFT) is used to investigate the effect of compressive strain on the structural, electronic, and optical properties of CAIB. The elastic constants follow the Born-Huang stability criterion and show the mechanical stability of the composition even under compressive strain. The Poisson's ratio in the range of 0.23 to 0.26 and B/G >1.75 indicate the ductile and soft nature of the material. The band gap increases monotonically without changing the direct nature of the band gap by increasing the compressive strain. However, the larger value of strain reproduces more dispersive conduction band minima and valence band maxima, resulting in lower effective masses and consequently larger carrier mobilities. The variations in the optical properties of CAIB are explored under compressive strain. The structural, electronic, and good photoresponse of the material in the visible and ultraviolet regions indicate the suitability of the material for flexible photovoltaics.","PeriodicalId":18648,"journal":{"name":"Modelling and Simulation in Materials Science and Engineering","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140660182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-16DOI: 10.1088/1361-651x/ad3a00
Orhan Gülcan, Kadir Günaydın, Aykut Tamer
Triply periodic minimal surface (TPMS) lattices have drawn great attention both in academic and industrial perspective due to their outstanding mechanical behaviours. Additive manufacturing (AM) modalities enable the production of these lattices very easily. However, dimensional inaccuracy is still one of the problems that AM still faces with. Manufacturing of these lattices with AM modalities, then measuring the critical dimensions and making design changes accordingly is a costly process. Therefore, it is necessary to predict the dimensional deviation of TPMS lattices before print is a key topic. This study focused on prediction of dimensional deviation of laser powder bed fusion (LPBF) produced gyroid, diamond, primitive, IWP and Fisher-Koch lattices by using thermomechanical simulations. TPMS type, unit cell size, volume fraction, functional grading and part orientation were selected as design variables. Results showed that all the design inputs have effects on dimensional accuracy of LPBF produced parts and TPMS type has the most critical factor. Based on analysis of variance analysis, an optimum lattice configuration was proposed to obtain the lowest dimensional deviation after LPBF build.
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