Mechanics of Materials最新文献_第10页

Fractional order strain and viscosity in the Moore–Gibson–Thompson thermoelastic diffusion model: A study of transient responses in one-dimensional half-space Moore-Gibson-Thompson热弹性扩散模型中的分数阶应变和黏度：一维半空间瞬态响应的研究

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-11-07 DOI: 10.1016/j.mechmat.2025.105542

Geetanjali Geetanjali , Pawan Kumar Sharma

In the mathematical modeling of viscoelastic materials such as biological tissues, polycrystalline metals, and high polymers, fractional order strain is widely adopted to highlight their rheological properties. Moreover, models incorporating fractional calculus provide more rational results. In this light, we consider fractional Moore–Gibson–Thompson model of generalized visco-thermoelastic-diffusion to study the transient responses of a one dimensional half space. The novelty of the present work lies in considering fractional order strain and fractional viscosity in the considered framework. Initially, the medium is kept at rest and at the boundary, thermal shock is applied in a stress free state. The basic equations and relations governing the problem are non-dimensionalized and solved in a Laplace transformed domain using the boundary restrictions. The solution of the problem is obtained in the original domain via a numerical inversion technique. This work aims to underline the impact of different models, fractional order strain, and viscosity parameters on physical quantities. Graphical representation of the results elucidates that fractional viscosity softens the stiffness in the distribution of field variables and fractional order strain eliminates the sudden increment in their peak points. Also, different models have varying degree of influence on all the field variables.

在生物组织、多晶金属和高聚物等粘弹性材料的数学建模中，广泛采用分数阶应变来突出其流变性能。此外，结合分数阶微积分的模型提供了更合理的结果。在这种情况下，我们考虑广义粘热弹扩散的分数阶Moore-Gibson-Thompson模型来研究一维半空间的瞬态响应。本工作的新颖之处在于在考虑的框架中考虑分数阶应变和分数阶粘度。最初，介质保持静止，在边界处，热冲击以无应力状态施加。控制问题的基本方程和关系是无量纲化的，并在拉普拉斯变换域中利用边界限制进行求解。通过数值反演技术在原域得到了问题的解。这项工作的目的是强调不同的模型，分数阶应变和粘度参数对物理量的影响。结果的图形表示表明，分数阶粘度软化了场变量分布中的刚度，分数阶应变消除了其峰值点的突然增量。不同的模型对各场变量的影响程度也不同。

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引用次数: 0

Investigating the interfacial behavior of van der Waals heterostructures with nano-inclusions: Molecular dynamics simulation and theoretical analysis 范德华异质结构与纳米内含物的界面行为研究：分子动力学模拟与理论分析

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-09-30 DOI: 10.1016/j.mechmat.2025.105514

Liqun Lou , Peijian Chen , Hao Liu , Guangjian Peng , Juan Peng

Interfacial properties of van der Waals (vdW) heterostructures are of crucial significance for precision instruments, microelectronics, mechanical and electrical engineering and so on. However, the lack of study on interfacial response of vdW heterostructures with nanoparticle greatly hinders the reliability and stability of various novel devices. Herein, we perform theoretical analysis and molecular dynamics simulation to explore the configuration and cohesive energy of vdW heterostructures with nano-inclusions. It is found that our proposed model functions well to predict morphologies of vdW heterostructure at the equilibrium state. The parameters dominating the formed morphology of vdW heterostructures are clarified. What is more, the interfacial behavior of vdW heterostructures can be modified by tuning the size, number, aggregation and interfacial interactions of nano-inclusions. The results should be helpful for not only improving the knowledge of surface/interface mechanics, but also guiding applications of two-dimensional materials and the corresponding vdW heterostructures.

范德华异质结构的界面特性在精密仪器、微电子、机电工程等领域具有重要意义。然而，缺乏对vdW异质结构与纳米颗粒界面响应的研究，极大地阻碍了各种新型器件的可靠性和稳定性。本文通过理论分析和分子动力学模拟来探讨含有纳米包体的vdW异质结构的构型和内聚能。结果表明，该模型能较好地预测vdW异质结构在平衡态的形貌。阐明了决定vdW异质结构形成形态的参数。此外，可以通过调节纳米夹杂物的大小、数量、聚集和界面相互作用来改变vdW异质结构的界面行为。研究结果不仅有助于提高表面/界面力学知识，而且对二维材料和相应的vdW异质结构的应用具有指导意义。

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引用次数: 0

Numerical modelling of the dynamic pull-out of steel fibers from cementitious materials 胶凝材料中钢纤维动态拉拔的数值模拟

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-09-25 DOI: 10.1016/j.mechmat.2025.105511

Bibiana Luccioni , Paula Argañaraz , Facundo Isla

Since fiber pull-out is the main reason for the toughness of fiber-reinforced cementitious composites, it is important to properly simulate this mechanism in dynamic models for this type of materials. Available experimental results show that the pull-out response of steel fibers embedded in concrete matrices exhibits sensitivity to the loading rate. This paper presents a model for the dynamic pull-out of steel fibers from cementitious composites. The model takes into account inertia effects and rate effects that influence the forces at the fiber-matrix interface, matrix micro cracking, mechanical anchorage and snubbing effects. The tangential stresses at the interface are calibrated based on experimental results obtained from pull-out tests of straight fibers performed at different loading rates, from quasi-static loading to impact loading, for different types of concrete matrix, including ultrahigh performance concrete (UHPC). The paper is complemented by the simulation of the pull-out of hooked end fibers at different loading rates and inclinations. The comparison with experimental results shows that the developed pull-out model is able to simulate the dynamic pull-out of steel fibers with different geometries and orientations from different types of concrete matrices. The inertia effects are negligible compared to the contribution of the other mechanisms to the pull-out response and to the effects due to the strain rate dependence of the fiber-matrix interface parameters.

由于纤维拔出是纤维增强胶凝复合材料韧性的主要原因，因此在这类材料的动力学模型中正确地模拟这一机制是很重要的。已有的试验结果表明，嵌入混凝土基体中的钢纤维的拉拔响应对加载速率具有敏感性。本文建立了胶凝复合材料中钢纤维的动态拉拔模型。该模型考虑了影响纤维-基体界面受力的惯性效应和速率效应、基体微裂纹效应、机械锚固效应和缓蚀效应。根据不同类型的混凝土基体（包括超高性能混凝土（UHPC））在不同加载速率（从准静态加载到冲击加载）下进行的直纤维拉拔试验结果，对界面处的切向应力进行了校准。本文还对不同加载速率和倾角下钩端纤维的抽拔进行了模拟。与试验结果的对比表明，所建立的拉拔模型能够模拟不同几何形状和方向的钢纤维从不同类型的混凝土基体中动态拉拔的过程。与其他机制对拔出响应的贡献以及纤维-基体界面参数应变速率依赖性的影响相比，惯性效应可以忽略不计。

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引用次数: 0

Micromechanical modeling and property prediction of bamboo with gradient random vascular bundles 梯度随机维管束竹的微观力学模型及性能预测

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-14 DOI: 10.1016/j.mechmat.2025.105527

Yubo Hou , Adel Noori , Kairan Zhang , Yuhan Zheng , Hao Wang , Yubin Lu

Bamboo has gained significant attention in sustainable buildings for its rapid growth rate and impressive mechanical properties comparable to wood. The volume fraction and gradient arrangement of vascular bundles directly influence the mechanical properties of bamboo. This paper proposes a novel gradient random distribution method, which can accurately restore the gradient distribution of bamboo vascular bundles along the radial direction of the culm wall. The aim is to uncover the relationship between the gradient distribution pattern of vascular bundles and the mechanical properties. The gradient random distribution method helps to transform the uniform random Representative Volume Element model into a gradient random distribution numerical model using the concept of coordinate transformation. The comparative analysis was conducted between the uniform random distribution method and the gradient random distribution method to predict the effective elastic properties of bamboo vascular bundles. The results indicated that elastic modulus and shear modulus of bamboo exhibit an exponential increase from the inner to the outer layers along the radial direction of the culm wall. Larger fiber spacing can slightly decrease the corresponding shear modulus. Moreover, the gradient random distribution method is capable of predicting accurately the elastic stiffness properties of full-sized bamboo culm compared to the uniform random distribution method.

竹子因其快速的生长速度和可与木材媲美的令人印象深刻的机械性能而在可持续建筑中获得了极大的关注。维管束的体积分数和梯度排列直接影响竹子的力学性能。本文提出了一种新的梯度随机分布方法，可以准确地恢复竹维管束沿茎壁径向的梯度分布。目的是揭示维管束的梯度分布模式与力学性能之间的关系。梯度随机分布方法利用坐标变换的概念，将均匀随机的代表性体元模型转化为梯度随机分布的数值模型。对均匀随机分布法和梯度随机分布法预测竹维管束有效弹性特性进行了对比分析。结果表明：竹材的弹性模量和剪切模量沿茎壁径向由内层向外层呈指数增长；较大的纤维间距可使相应的剪切模量略有降低。与均匀随机分布法相比，梯度随机分布法能较准确地预测全尺寸竹竿的弹性刚度特性。

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引用次数: 0

Statistics of maximum stress for elastic wave propagation in a random porous solid 弹性波在随机多孔固体中传播的最大应力统计

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-01 Epub Date: 2025-09-23 DOI: 10.1016/j.mechmat.2025.105508

Shiwen Feng , Q.M. Li

The stochastic characteristics of elastic wave scattering in random porous solids lead to the complexity and uncertainty for the determination of local maximum stress. There are limited studies to predict and estimate the maximum stress in such medium mainly due to the lack of efficient and accurate modeling tools. In order to address this issue, this work presents a new approach to quantify the statistics of maximum stress induced by multiple wave scattering effects in such medium. By combining the high-fidelity finite element method with Monte Carlo simulation, this work provides a comprehensive framework for evaluating the mean, standard deviation and probability distribution of maximum stress in random porous solids. It is demonstrated that the mean and standard deviation of maximum stress depend highly on the wave frequency and the correlations among cavities. The probability density function of maximum stress is analytically formulated by Burr Ⅻ distribution where the wave frequency and the correlation among cavities are taken into account jointly. The related parameters involved in the statistical distribution are estimated by maximum likelihood method and the Kolmogorov-Smirnov test is adopted to examine the goodness of fitting distribution. The heavy-tailed behavior observed in the statistical distribution is elaborated by linking to the interaction effects of waves with random microstructures, which is crucial for the dynamic failure assessment of porous solids. Finally, the dynamic stress concentration associated with maximum stress in random porous solid is investigated, which potentially relates to the scatterer resonance effects. This work facilitates the understanding of wave-induced dynamic stress in heterogeneous media, providing a statistical approach for dynamic failure assessment in random porous solids.

随机多孔固体中弹性波散射的随机特性导致了局部最大应力计算的复杂性和不确定性。由于缺乏高效、准确的模拟工具，对此类介质中最大应力的预测和估计研究有限。为了解决这一问题，本文提出了一种新的方法来量化这种介质中由多重波散射效应引起的最大应力的统计。通过将高保真有限元法与蒙特卡罗模拟相结合，为随机多孔固体中最大应力的均值、标准差和概率分布提供了一个综合的评估框架。结果表明，最大应力的平均值和标准差在很大程度上取决于波的频率和空腔之间的相关性。最大应力的概率密度函数由BurrⅫ分布解析表示，同时考虑了波频和空腔间的相关性。采用极大似然法对统计分布中涉及的相关参数进行估计，并采用Kolmogorov-Smirnov检验检验拟合分布的优度。在统计分布中观察到的重尾行为通过将波与随机微观结构的相互作用效应联系起来加以阐述，这对于多孔固体的动态破坏评估至关重要。最后，研究了随机多孔固体中与最大应力相关的动应力集中，这可能与散射共振效应有关。这项工作有助于理解非均质介质中波动引起的动应力，为随机多孔固体的动态破坏评估提供了一种统计方法。

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引用次数: 0

Thermo-mechanical experiments for deformation twinning in high-purity titanium 高纯钛变形孪晶的热力学实验

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-01 Epub Date: 2025-09-10 DOI: 10.1016/j.mechmat.2025.105479

Akhilesh Pedgaonkar , Anderson Nascimento , Irene J. Beyerlein , Curt A. Bronkhorst

We present thermomechanical experiments with high-resolution Electron Back Scatter Diffraction (EBSD) maps to study deformation twinning in high-purity

α

titanium. The experiments were simple compression tests conducted at room temperature (

23 ° C

) and cold temperature (

- 45 ° C

to

- 60 ° C

). Large strain experiments (strain

ɛ = 0.4

) were conducted to understand the overall thermo-mechanical response of the material. Small-strain experiments (strain

ɛ = 0.03

to 0.05) were conducted and analyzed with EBSD to study the nucleation and evolution of deformation twins. We observed that the twin area fraction increases with strain for both room and cold temperature samples, but the mechanisms are distinct at small strains. Thickening of twins is prominent at room temperature, whereas the formation of new twins is prominent at cold temperatures. The twinning analysis also reveals that Basinski-type hardening has a significant impact on the early-stage hardening. There is also some evidence to suggest that more twins nucleate inside the grains rather than at the grain boundaries at colder temperatures. This work aims to provide a dataset for validating crystal plasticity models for deformation twinning in titanium.

本文利用高分辨率电子反向散射衍射（EBSD）图进行了热力学实验，研究了高纯度α钛的变形孪晶。实验是在室温（23°C）和低温（- 45°C至- 60°C）下进行的简单压缩试验。通过大应变实验（应变=0.4）了解材料的整体热-力学响应。利用EBSD进行小应变实验（应变=0.03 ~ 0.05），研究变形孪晶的形核演化规律。我们观察到，室温和低温样品的孪晶面积分数随应变的增加而增加，但在小应变下，其机制是不同的。孪晶的增厚在室温下是显著的，而新孪晶的形成在低温下是显著的。孪生分析还表明，basinski型硬化对早期硬化有显著影响。还有一些证据表明，在较冷的温度下，更多的孪晶在晶粒内部而不是在晶界处成核。本工作旨在为验证钛变形孪晶的晶体塑性模型提供数据集。

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引用次数: 0

Out-of-plane fracture in plane strain conditions: A novel criterion with analytical and experimental evaluation in thick PUR foam 平面应变条件下的面外断裂：一种具有分析和实验评价的新判据

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-01 Epub Date: 2025-09-10 DOI: 10.1016/j.mechmat.2025.105499

Mohammad Mahdi Touiserkani, Mahdi Heydari-Meybodi

The brittle fracture of thick polyurethane (PUR) foam is investigated in this study through both experimental and theoretical approaches under out-of-plane, Mixed-Mode I/III, loading conditions. Experimental tests are conducted on Edge-Notched Disc Bend (ENDB) samples to collect some new fracture data for predicting the Mixed-Mode I/III fracture behavior of rigid PUR foam. Additionally, the fracture toughness values are determined using finite element analysis. Theoretical predictions are then made using a new modification of the Maximum Principal Stress (MPS) criterion, termed ECD-MPS. Indeed, the Effective Critical Distance (ECD) concept is incorporated into the conventional MPS criterion in plane strain conditions, highlighting that the critical distance is influenced by both the material properties and fracture modes. A comparative analysis of experimental and theoretical results demonstrates that the ECD-MPS criterion provides high accuracy in predicting out-of-plane fracture. To further validate the findings, the results of ECD-MPS criterion are compared with those from two other fracture criteria: the classical MPS and Strain Energy Density (SED). Moreover, the validity of new criterion is further supported by its alignment with experimental findings from previous research.

本文采用实验和理论相结合的方法研究了厚聚氨酯（PUR）泡沫在面外、I/III混合模式加载条件下的脆性断裂。通过对边缘缺口盘弯曲（ENDB）试样进行实验测试，为预测硬质聚氨酯泡沫的I/III混合模式断裂行为收集新的断裂数据。此外，采用有限元分析确定了断裂韧性值。然后使用最大主应力（MPS）标准的新修正，称为ECD-MPS，进行理论预测。事实上，在平面应变条件下，有效临界距离（ECD）概念被纳入了传统的MPS准则，强调了临界距离受到材料特性和断裂模式的影响。实验结果与理论结果的对比分析表明，ECD-MPS准则在预测面外裂缝方面具有较高的精度。为了进一步验证研究结果，将ECD-MPS标准的结果与其他两种断裂标准的结果进行了比较：经典MPS和应变能密度（SED）。此外，新标准与以往研究的实验结果一致，进一步支持了新标准的有效性。

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引用次数: 0

The influence of material ductility on the dynamic fracture of 3D-printed PH15-5 steel lattices 材料延展性对3d打印PH15-5钢晶格动态断裂的影响

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-01 Epub Date: 2025-08-26 DOI: 10.1016/j.mechmat.2025.105481

Y. Boim , A. Shirizly , D. Rittel

This study focuses on the fracture mechanics of notched lattice structures under mode I and II impact conditions and examines the influence of material ductility on their failure mechanisms. Lattice specimens, made of PH15-5 stainless steel, were additively manufactured using laser-powder bed fusion (L-PBF). The specimens were tested in two conditions (as received – “ductile”, and H900 treated – “brittle”), resulting in lower and higher ductility to failure, respectively. Dynamic fracture behavior was tested using the one-point impact technique (for both modes I and II), together with finite element analysis (FEA) and scanning electron fractographic analysis. Large and small cell sizes were manufactured, preserving the lattice's density. In mode I, fracture propagation consistently occurred by sequential strut fracture. By contrast, under mode II loading, fracture propagates simultaneously in specimens with large unit cells, but sequentially in those with small unit cells, independent of the material condition. Specimens with a higher ductility failed by ductile fracture characterized by dimples. However, in the brittle state, the fracture mechanism was influenced by the unit cell size: large unit cell specimens showed a mixed fracture mode (dimples and cleavage), whereas small unit cells exhibited a distinctly brittle fracture with cleavage facets. These trends were observed irrespective of the loading mode. Overall, dynamic fracture propagated significantly faster in the brittle specimens, indicating a reduced capacity for impact energy absorption.

本文研究了缺口点阵结构在I型和II型冲击条件下的断裂力学，并考察了材料延展性对其破坏机制的影响。采用激光-粉末床熔融（L-PBF）法制备了PH15-5不锈钢的点阵试样。试样在两种条件下进行测试（接收-“韧性”和H900处理-“脆性”），分别导致较低和较高的破坏延展性。采用单点冲击技术（ⅰ和ⅱ两种模式），结合有限元分析（FEA）和扫描电子断口分析，测试了动态断裂行为。大大小小的电池尺寸被制造出来，保持了晶格的密度。在模式I中，裂缝扩展始终以连续的支杆断裂方式发生。相比之下，在II型加载下，断裂在大单元胞元试件中同时扩展，而在小单元胞元试件中依次扩展，与材料条件无关。具有较高延性的试样发生以韧窝为特征的韧性断裂。然而，在脆性状态下，断裂机制受单位细胞尺寸的影响：大单位细胞样品表现出混合断裂模式（韧窝和解理），而小单位细胞则表现出明显的脆性断裂和解理面。这些趋势与加载模式无关。总体而言，脆性试样的动态断裂扩展明显更快，表明冲击能量吸收能力降低。

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引用次数: 0

Phase-field modeling of multivariant martensitic phase transition in nanoscale NiTi shape memory alloys using strain-based Landau free energy 基于应变基朗道自由能的纳米级NiTi形状记忆合金多变量马氏体相变相场建模

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-01 Epub Date: 2025-08-20 DOI: 10.1016/j.mechmat.2025.105474

Mojtaba Adaei-Khafri, Mohammad Javad Ashrafi, Fathollah Taheri-Behrooz

In this study, we employ the thermodynamically consistent three-dimensional Landau model and extend it to investigate the B2 (cubic)–to–B19′ (monoclinic) phase transition in NiTi shape memory alloys at the nanoscale. The model describes transformations between austenite and martensitic variants, as well as transformations between martensitic variants. We derive the elasticity and phase-field coupling equations for multiple martensite phases and solve two-dimensional problems using the finite element method implemented in COMSOL software. A key novelty of this work is the utilization of the internal strain energy function of the NiTi phase transformation to apply the thermodynamic conditions of phase transformation to calculate the coefficients in the energy equations, ensuring accurate and physically meaningful material parameters for the phase-field model. We evaluate and validate the energy, width, and interface velocity for both stress- and temperature-induced phase transformations against existing research and analytical methods. Numerical results for martensitic variants phase transformations under stress- and temperature-induced conditions with different boundary conditions are presented and analyzed. The results demonstrate variations in phase propagation and final stable phase configurations, providing insights into the nanoscale behavior of NiTi shape memory alloys. The findings, obtained through derived coefficients and simulations, demonstrate that NiTi exhibits superior transformation kinetics compared to NiAl, attributed to its lower energy barrier, thermoelastic behavior, and faster phase transformation and growth. These conclusions are supported by both simulation results and existing literature.

在这项研究中，我们采用了热力学一致的三维朗道模型，并将其扩展到纳米尺度上研究了NiTi形状记忆合金中B2（立方）到b19 '（单斜）的相变。该模型描述了奥氏体和马氏体变体之间的转换，以及马氏体变体之间的转换。我们推导了多个马氏体相的弹性和相场耦合方程，并利用COMSOL软件实现的有限元方法求解了二维问题。这项工作的一个关键新颖之处在于利用NiTi相变的内部应变能函数来应用相变的热力学条件来计算能量方程中的系数，从而确保相场模型的材料参数准确且具有物理意义。针对现有的研究和分析方法，我们评估并验证了应力和温度诱导相变的能量、宽度和界面速度。给出并分析了不同边界条件下马氏体变异体在应力和温度诱导条件下相变的数值结果。结果显示了相扩展和最终稳定相结构的变化，为镍钛形状记忆合金的纳米级行为提供了见解。通过推导系数和模拟得到的结果表明，与NiAl相比，NiTi具有更低的能势、热弹性行为、更快的相变和生长，表现出更好的转变动力学。这些结论得到了仿真结果和已有文献的支持。

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引用次数: 0

Enhanced high-temperature creep resistance in gradient nanograined Fe-Zr alloy via gradient Zr segregation stabilizing grain boundary 通过梯度Zr偏析稳定晶界提高梯度纳米晶Fe-Zr合金的高温抗蠕变性能

IF 4.1 3区材料科学 Q2 MATERIALS SCIENCE, MULTIDISCIPLINARY

Mechanics of Materials

Pub Date : 2025-12-01 Epub Date: 2025-09-27 DOI: 10.1016/j.mechmat.2025.105513

Daqian Xu , Zhifeng Huang , Hao Li , Vladyslav Turlo , Like Xu , Qiang Shen , Fei Chen

Fine and ultrafine grains in the gradient nanograined (GNG) structure exhibit low creep resistance. As these grains grow, they will further influence the hetero-deformation behavior when interacting with coarse grains under tensile loading. Solute segregation could be effective for stabilizing nanograins, but the distribution of solute atoms and its influence on the structure-performance relationship in the GNG structure remain unclear. Here, the Zr solute segregation gradient is found energetically favorable in the Fe-Zr GNG alloy based on molecular dynamics simulations, where the solute concentration at GBs shows a gradient distribution across the GNG structure. This dual heterogeneity contributes to improved creep resistance while also retaining the hetero-deformation induced strengthening nature of the GNG structure. A pseudo-composite structure is then demonstrated from the dual heterogeneity structure design: the finer grain region with higher segregation concentration, which acts as the thermodynamical stabilizer to enhance creep resistance; and the coarser grain region with smaller segregation concentration, which acts as plastic deformer to provide necessary hetero-deformation accommodation ability. Our work introduces segregation-induced concentration gradient into traditional heterogeneous materials and presents a new route for improving the creep resistance and tensile properties of heterostructure materials.

梯度纳米晶（GNG）结构中的细晶粒和超细晶粒表现出较低的抗蠕变性能。随着这些晶粒的长大，它们将进一步影响拉伸载荷下与粗晶粒相互作用时的异质变形行为。溶质偏析可以有效地稳定纳米颗粒，但在GNG结构中，溶质原子的分布及其对结构-性能关系的影响尚不清楚。基于分子动力学模拟，发现Fe-Zr GNG合金中Zr溶质偏析梯度在能量上是有利的，其中GBs处的溶质浓度在整个GNG结构中呈现梯度分布。这种双重非均质性有助于提高抗蠕变性能，同时也保留了GNG结构的非均质变形强化性质。通过双非均质结构设计，得到了伪复合结构：具有较高偏析浓度的细晶区作为热稳定剂，增强了材料的抗蠕变性能；晶粒较粗，偏析浓度较小，起到塑性变形的作用，提供了必要的异质变形调节能力。本研究将偏析诱导浓度梯度引入到传统异质材料中，为提高异质结构材料的抗蠕变性能和拉伸性能提供了一条新的途径。

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引用次数: 0