Mechanics of Materials最新文献_第8页

Molecular insights of acoustic softening mechanism in ultrasonic vibration-assisted tensile deformation of SiC/Al composites 超声振动辅助SiC/Al复合材料拉伸变形声软化机理的分子研究

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-30 DOI: 10.1016/j.mechmat.2025.105539

Ben An, Jiaqi Li, Zhenshun Li, Diping Wu, Rui Li

Ultrasonic vibration (UV) has been widely utilized in metal forming processes owing to its ability to enhance material formability. However, the microscopic mechanism governing the plastic deformation of SiC/Al composites under UV remains unclear, thereby significantly restricting their implementation in ultra-precision machining applications. To address this gap, a particle-reinforced composite model was developed using the Random Sequential Adsorption (RSA) algorithm, and molecular dynamics simulations were conducted to compare the tensile behavior of SiC/Al composites under UV and non-UV conditions. The effects of SiC volume fraction and particle size on mechanical properties were systematically evaluated and the mechanism of UV-induced acoustic softening was discussed. The results showed that the increase of SiC particle size from 16 Å to 32 Å and the decrease of volume fraction from 13.8 % to 8.3 % diminished both tensile strength and elastic modulus. UV enhanced atomic kinetic energy and grain boundary potential energy, thereby facilitating dislocation annihilation and suppressing dislocation pile-ups, ultimately reducing flow stress. The stress reduction due to acoustic softening was correlated with dislocation evolution dynamics and increases with ultrasonic amplitude. This work sheds light on theoretical framework for optimizing the efficient processing of particle-reinforced SiC/Al composites under UV.

超声振动（UV）由于能够提高材料的成形性，在金属成形工艺中得到了广泛的应用。然而，控制SiC/Al复合材料在UV下塑性变形的微观机制尚不清楚，从而极大地限制了其在超精密加工中的应用。为了解决这一问题，研究人员利用随机顺序吸附（RSA）算法建立了颗粒增强复合材料模型，并进行了分子动力学模拟，比较了SiC/Al复合材料在紫外线和非紫外线条件下的拉伸行为。系统评价了碳化硅体积分数和粒径对力学性能的影响，探讨了紫外光声软化的机理。结果表明：SiC粒径从16 Å增大到32 Å，体积分数从13.8%减小到8.3%，拉伸强度和弹性模量均降低；UV提高原子动能和晶界势能，从而促进位错湮灭，抑制位错堆积，最终降低流动应力。声软化引起的应力减小与位错演化动力学相关，并随超声振幅的增大而增大。本研究为优化UV下颗粒增强SiC/Al复合材料的高效加工提供了理论框架。

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引用次数: 0

Delineating strain-rate hardening and inertial effects on dynamic hardness of materials 描述了应变率硬化和惯性效应对材料动态硬度的影响

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-11 DOI: 10.1016/j.mechmat.2025.105523

Zahra Ghasemi , Tiago dos Santos , Debjoy D. Mallick , José A. Rodríguez-Martínez , Ankit Srivastava

We examine the interplay between strain-rate hardening and structural inertia in dynamic indentation, with the objective of identifying when dynamic hardness reflects intrinsic material response versus when it is influenced by inertia. Finite element simulations and theoretical calculations – based on a dynamic cavity expansion model – are performed for materials described by a strain- and strain-rate-dependent constitutive model with thermal softening. The analysis spans a broad range of indentation velocities, depths, material densities, and strain-rate sensitivity exponents. Our results show that at relatively low to moderate indentation velocities, dynamic hardness can be interpreted as an intrinsic material property. However, at sufficiently high velocities, the indentation response is significantly influenced by inertia-induced resistance, manifested by a rapid increase in hydrostatic stress and, consequently, in dynamic hardness. The extent of this resistance scales with indentation strain rate, indentation depth, and material density. We introduce a normalization approach that, for a given material, accounts for inertia by scaling dynamic hardness and indentation strain rate with reference functions that depend on indentation velocity. This procedure enables the identification of the loading rate at which inertia begins to dominate the indentation response and allows data across a wide range of indentation strain rates and depths to be interpreted in terms of the material’s intrinsic strain-rate-dependent constitutive behavior. The excellent agreement between finite element simulations and theoretical predictions underscores the robustness of the proposed approach and establishes a foundation for extracting strain-rate-sensitive material properties from dynamic indentation experiments.

我们研究了动态压痕中应变率硬化和结构惯性之间的相互作用，目的是确定动态硬度是反映材料的固有响应还是受惯性影响。基于动态空腔膨胀模型的有限元模拟和理论计算，对由应变和应变率相关的热软化本构模型描述的材料进行了模拟和理论计算。该分析涵盖了广泛的压痕速度、深度、材料密度和应变率灵敏度指数。我们的结果表明，在相对低到中等压痕速度下，动态硬度可以解释为材料的固有特性。然而，在足够高的速度下，压痕响应明显受到惯性诱导阻力的影响，表现为静水应力的迅速增加，从而导致动态硬度的增加。这种阻力的程度与压痕应变率、压痕深度和材料密度有关。我们引入了一种归一化方法，对于给定的材料，通过缩放动态硬度和压痕应变率与依赖于压痕速度的参考函数来解释惯性。这一过程可以确定惯性开始主导压痕响应的加载速率，并允许在大范围内的压痕应变率和深度的数据被解释为材料的固有应变率相关的本构行为。有限元模拟与理论预测之间的良好一致性强调了所提出方法的鲁棒性，并为从动态压痕实验中提取应变率敏感材料性能奠定了基础。

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引用次数: 0

A physics-based crystal plasticity model of nickel-based single crystal superalloy for different loading conditions under a wide temperature range 基于物理的镍基单晶高温合金在宽温度范围内不同加载条件下的晶体塑性模型

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.2025.105528

Jiaxuan Wang , Rou Du , Liu Chen , Hansong Ma , Xiaoming Liu , Yueguang Wei

Nickel-based single crystal (NBSC) superalloys are extensively used in the fabrication of turbine blades for aero engines, where their deformation behaviours play a critical role in ensuring flight safety. The deformation behaviours are governed by complex micro-scale mechanisms, such as matrix slip, precipitate shearing, interface dislocation pile-up, dislocation climb, coarsening, and rafting. However, many existing models either inadequately account for the underlying deformation mechanisms or rely heavily on temperature-sensitive material parameters, both of which undermine their predictive accuracy and generalizability under diverse loading and thermal conditions. To address these limitations, this study develops a robust and versatile crystal plasticity model that incorporates the above mechanisms. The model decouples temperature effects from constitutive parameters to mitigate parameter sensitivity to temperature variations. Additionally, a parameter decoupling strategy is employed to reduce the number of adjustable parameters and facilitate their identification. The model is validated against experimental data for the DD6 superalloy under uniaxial tension, creep, and low-cycle fatigue tests conducted across a wide temperature range (20–980 °C). The predicted mechanical responses demonstrate good agreement with the experimental results. Finally, the model is applied to simulate the mechanical behaviour of a specimen with inclined cooling holes. The model gives a nearly linear response of creep displacement, which matches well with the experiments.

镍基单晶高温合金广泛应用于航空发动机涡轮叶片的制造，其变形行为对保证飞行安全起着至关重要的作用。变形行为受基体滑移、析出相剪切、界面位错堆积、位错爬升、粗化和漂流等复杂微观机制控制。然而，许多现有的模型要么不能充分考虑潜在的变形机制，要么严重依赖于温度敏感的材料参数，这两者都破坏了它们在不同载荷和热条件下的预测准确性和通用性。为了解决这些限制，本研究开发了一个包含上述机制的健壮且通用的晶体塑性模型。该模型将温度效应与本构参数解耦，降低了本构参数对温度变化的敏感性。此外，采用参数解耦策略减少了可调参数的数量，便于辨识。该模型通过DD6高温合金在单轴拉伸、蠕变和宽温度范围（20-980°C）下的低周疲劳试验数据进行了验证。预测的力学响应与实验结果吻合较好。最后，将该模型应用于具有倾斜冷却孔的试样的力学行为模拟。该模型给出了蠕变位移的近似线性响应，与实验结果吻合较好。

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引用次数: 0

Soft orthotropic hyperelastic lattice structures: Numerical homogenization and experimental validation 软正交各向异性超弹性晶格结构：数值均匀化和实验验证

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-28 DOI: 10.1016/j.mechmat.2025.105534

Dror Raf, Itay Magen, Amit Ashkenazi, Lee Jordan, Dana Solav

Lattice structures have become increasingly popular in various applications due to their lightweight and wide range of effective properties that can be locally tailored by adjusting their geometric features. Finite element (FE) simulations are commonly used to predict their mechanical response and inform inverse design algorithms. However, these simulations pose significant computational demands due to the large number of elements needed for meshing lattice geometries. This challenge can be addressed by replacing lattice geometries with a homogeneous solid of equivalent mechanical properties, a process known as homogenization. However, determining a suitable constitutive model and parameters is difficult, particularly when the response is nonlinear and anisotropic. To this end, this study presents a method for numerically homogenizing orthotropic lattice structures subjected to large elastic deformations. FE simulations of lattice unit cells are employed to quantify their nonlinear elastic response under large uniaxial tension, compression, and simple shear deformations. The simulation results are then used to fit the constitutive model parameters for the effective behavior of the unit cells, employing a Fung orthotropic hyperelastic formulation. The proposed homogenization method is validated through comparisons with full-geometry simulations and compression experiments on beam-based cubic lattice structures manufactured from thermoplastic polyurethane (TPU) using selective laser sintering (SLS). Furthermore, we compare the response of a beam with orthotropic unit cells under bending, which activates multiple deformation modes. The results demonstrate the feasibility and computational efficiency of the proposed homogenization method, highlighting the potential of this approach for efficient modeling and design of lattice structures in engineering applications.

晶格结构由于其轻量化和广泛的有效特性，可以通过调整其几何特征进行局部定制，因此在各种应用中越来越受欢迎。有限元（FE）模拟通常用于预测其力学响应并为反设计算法提供信息。然而，由于网格几何所需的大量元素，这些模拟提出了显著的计算需求。这一挑战可以通过用具有等效力学性能的均匀固体取代晶格几何来解决，这一过程被称为均质化。然而，确定一个合适的本构模型和参数是困难的，特别是当响应是非线性和各向异性的。为此，本研究提出了一种大弹性变形下正交各向异性晶格结构的数值均匀化方法。采用有限元模拟的方法，量化了晶格单元胞在大单轴拉伸、压缩和简单剪切变形下的非线性弹性响应。然后利用模拟结果拟合单元胞的有效行为的本构模型参数，采用Fung正交各向异性超弹性公式。通过对热塑性聚氨酯（TPU）采用选择性激光烧结（SLS）制备的梁基立方晶格结构进行全几何模拟和压缩实验，验证了所提出的均匀化方法。此外，我们比较了正交各向异性单元格梁在弯曲作用下的响应，这激活了多种变形模式。结果证明了所提出的均匀化方法的可行性和计算效率，突出了该方法在工程应用中高效建模和设计晶格结构的潜力。

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引用次数: 0

An accelerated shock fatigue life model for complex shock loads with load dispersion 考虑载荷分散的复杂冲击载荷的加速冲击疲劳寿命模型

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-30 DOI: 10.1016/j.mechmat.2025.105535

Yi Sun, Shuai Ma, Yongbin Dang, Zhiqiang Yang

This paper presents an accelerated shock fatigue life model based on load dispersion, which utilizes the experimental life data under high-magnitude loads to assess whether the structure meets the fatigue life design requirements under its original load conditions, thereby improving the experimental efficiency. Firstly, a shock fatigue life database is established by combining experiments with finite element analysis. Then, the shock load dispersion effect is quantified by data fitting, and the relationship between the shock response spectrum parameters and the Weibull parameters is obtained. Finally, a new accelerated shock fatigue life model is established by introducing a relative dispersion factor based on the inverse power law model. Taking BGA solder joints as an example, the shock fatigue damage equivalent boundary of BGA solder joints is calculated. The results show that the error between the predicted boundary and the actual boundary is in the range of −5 %–7 %, verifying the effectiveness of the model.

本文提出了一种基于载荷分散的加速冲击疲劳寿命模型，利用高量级载荷下的实验寿命数据来评估结构在其原始载荷条件下是否满足疲劳寿命设计要求，从而提高了实验效率。首先，将实验与有限元分析相结合，建立了冲击疲劳寿命数据库；然后，通过数据拟合量化冲击载荷弥散效应，得到冲击响应谱参数与威布尔参数之间的关系。最后，在逆幂律模型的基础上引入相对弥散因子，建立了新的加速冲击疲劳寿命模型。以BGA焊点为例，计算了BGA焊点的冲击疲劳损伤等效边界。结果表明，预测边界与实际边界的误差在−5% ~ 7%之间，验证了模型的有效性。

引用次数: 0

Mechanical behaviour and damage assessment of AlSi10Mg lattice structures fabricated by laser powder bed fusion under static and fatigue loading 静态和疲劳载荷下激光粉末床熔合制备AlSi10Mg晶格结构的力学行为及损伤评估

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-31 DOI: 10.1016/j.mechmat.2025.105530

Hugo Soul , Vladimir Brailovski , Alejandro Yawny

The monotonic and fatigue mechanical behaviour of diamond cell lattice structures fabricated by Laser Powder Bed Fusion (L-PFB) from Al10SiMg powder with two relative densities (∼40 and 50 %) was investigated. Pseudostatic tensile, compression and cyclic uniaxial loading tests were carried out with stress ratios R of 0.1 (pull-pull), 10 (push-push) and −1 (symmetric pull-push). The lattice specimens' design incorporated fully dense end regions to facilitate clamping and enable the application of both tensile and compressive loads. Furthermore, smooth graded transitions between the central region of constant relative density and the fully dense extremities were implemented to mitigate stress concentration effects during cyclic loading. The study included measurements of the Young's modulus, the yielding behaviour, the strength, the ductility and the fracture characteristics, and involved a comparison between the tensile and compression monotonic test results, including the collapse and crush patterns associated with the tests. The fatigue test results were then used to analyze damage accumulation over the specimens' lifetimes as indicated by the measured strain response, which exhibited a three-stage pattern. Subsequently, S-N diagrams were built as a function of the global stress amplitude and global maximum stress applied. A novel local stress parameter, encompassing the maximum normal and shear stresses, was proposed as an alternative method for rationalizing fatigue data for lattice structures. This comprehensive investigation provides insight into the mechanical performance and fatigue characteristics of diamond cell lattice structures under various loading conditions.

研究了相对密度（~ 40%和50%）的Al10SiMg粉末激光粉末床熔合（L-PFB）制备的金刚石细胞晶格结构的单调力学行为和疲劳力学行为。拟静力拉伸、压缩和循环单轴加载试验，应力比R分别为0.1（拉-拉）、10（推-推）和−1（对称拉-推）。晶格试样的设计结合了完全密集的端区，以方便夹紧，并使拉伸和压缩载荷的应用。此外，在恒定相对密度的中心区域和完全密集的末端之间实现平滑的渐变过渡，以减轻循环加载时的应力集中效应。该研究包括杨氏模量、屈服行为、强度、延性和断裂特征的测量，并涉及拉伸和压缩单调试验结果之间的比较，包括与试验相关的崩溃和挤压模式。然后使用疲劳试验结果来分析试样寿命期间的损伤积累，这表明测量的应变响应呈现出三个阶段的模式。随后，建立了S-N图，作为全局应力幅值和全局最大应力的函数。提出了一种新的局部应力参数，包括最大法向应力和最大剪应力，作为优化晶格结构疲劳数据的替代方法。这项全面的研究提供了对不同载荷条件下金刚石细胞晶格结构的力学性能和疲劳特性的深入了解。

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引用次数: 0

A sole-material hierarchical lattice structure with simultaneous tunable thermal expansion and low-frequency bandgap properties 具有同时可调热膨胀和低频带隙特性的鞋底材料分层晶格结构

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-30 DOI: 10.1016/j.mechmat.2025.105537

Yunhao Zhang , Hao Xia , Zhendong Sha

Hierarchical lattice structures (HLSs) characterized by multiscale and self-similar geometries have attracted increasing attention due to their exceptional mechanical and functional performance. However, almost HLSs focus on bi-material systems, which often suffer from interfacial mismatches. Herein, we propose an HLS composed of a sole-material system of Ti₅Si₃ with an anisotropic characteristic. This design eliminates interfacial mismatches inherent in bi-material systems and leverages geometry-anisotropy coupling to achieve tunable behavior with reliable and predictable performance. A theoretical framework is established to derive the expressions of thermal expansion coefficient (α). Bloch wave theory and eigenfrequency simulations are employed to evaluate bandgap characteristics and wave propagation behavior. Our results demonstrate that the α is significantly reduced at a small internal angle of 30° and high aspect ratio of 15, achieving a minimum value of 2.56 ppm K⁻¹ at the third hierarchical level. Accompanied by the decrease in α values, low-frequency bandgaps below 1000 Hz occur. It is also demonstrated that with the increase in hierarchical level, multiple narrower bandgaps are observed due to altered vibration mode patterns. In contrast with previous bi-material HLSs, our sole-material HLS exhibits not only simple manufacturability but also multi-functionalization.

层次晶格结构具有多尺度和自相似的几何特征，由于其优异的力学和功能性能而受到越来越多的关注。然而，几乎所有的hss都集中在双材料系统上，这些系统经常受到界面不匹配的影响。在此，我们提出了一个由具有各向异性特征的Ti5Si3鞋底材料体系组成的HLS。这种设计消除了双材料系统固有的界面不匹配，并利用几何各向异性耦合来实现具有可靠和可预测性能的可调行为。建立了推导热膨胀系数（α）表达式的理论框架。采用布洛赫波理论和特征频率模拟来评估带隙特性和波的传播行为。结果表明，在30°的小内角和15的高长宽比下，α显著降低，在第三层次上达到最小值2.56 ppm K−1。伴随着α值的减小，出现了低于1000hz的低频带隙。结果还表明，随着分层水平的增加，由于振动模式的改变，观察到多个更窄的带隙。与以前的双材料HLS相比，我们的鞋底材料HLS不仅具有简单的可制造性，而且具有多功能。

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引用次数: 0

Development of generalized yield surface of fly ash microbubble composites using nonlinear multiscale analysis 粉煤灰微泡复合材料广义屈服面非线性多尺度分析研究

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-25 DOI: 10.1016/j.mechmat.2025.105532

Abdalla Elbana, Amar Khennane

This study presents a multiscale framework to model the nonlinear constitutive behavior of particulate composites containing hollow ceramic inclusions. The composite consists of an elasto-plastic epoxy matrix, plastic in compression and linear elastic in tension, reinforced with brittle, linearly elastic fly ash microbubbles

(40 {A l}_{2} O_{3} - 60 S i O_{2}) .

Representative volume elements (RVEs) with varying particle volume fractions (15–45 %) are used to capture the micromechanical response under multiaxial loading. A structured modeling strategy is employed, including the idealization of fly ash microbubbles as hollow spheres and calibration of cohesive zone models using experimental data and SEM fracture imaging. A three-dimensional yield surface is constructed from RVE simulations, incorporating pressure sensitivity and Lode angle dependence. A custom VUMAT subroutine was developed to implement the proposed yield function which incorporates compressive hardening, tensile softening via a fracture strain limit and a viscosity-based regularization scheme enhances stability in explicit dynamic simulations, especially under small strain increments with low hardening modulus or perfect plasticity. This unified micromechanics-driven approach enables simulation of progressive failure in syntactic foams and related composites.

本研究提出了一个多尺度框架来模拟含空心陶瓷夹杂颗粒复合材料的非线性本构行为。该复合材料由弹塑性环氧树脂基体组成，具有压缩塑性和拉伸线性弹性，并用脆性线弹性粉煤灰微泡（40Al2O3−60SiO2）增强。采用具有不同颗粒体积分数（15 - 45%）的代表性体积元（RVEs）来捕捉多轴加载下的微力学响应。采用结构化建模策略，包括将粉煤灰微气泡理想化为空心球体，并利用实验数据和SEM裂缝成像对黏结带模型进行校准。通过RVE模拟，结合压力敏感性和Lode角依赖性，构建了三维屈服面。开发了定制的VUMAT子程序来实现所提出的屈服函数，该函数结合了压缩硬化、断裂应变极限拉伸软化和基于粘度的正则化方案，增强了显式动态模拟的稳定性，特别是在低硬化模量或完美塑性的小应变增量下。这种统一的微观力学驱动方法可以模拟复合泡沫和相关复合材料的渐进破坏。

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引用次数: 0

Enhancing nonlinear viscoelastic modeling of elastomers through neural networks: A deep rheological element 通过神经网络增强弹性体的非线性粘弹性建模：一种深度流变元件

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-16 DOI: 10.1016/j.mechmat.2025.105525

Federico Califano , Jacopo Ciambella

An established method for incorporating inelastic constitutive equations into finite element software is the use of rheological elements, assembled in series or in parallel, to describe the constitutive response at each material point. This approach can be extended to finite strains by exploiting the multiplicative decomposition of the deformation gradient. In this study, we propose an hybrid approach that integrates traditional elements with elements, with constitutive equations defined through deep neural networks (DNNs), into an assemblage of standard rheological elements. We formulate DNNs to guarantee thermodynamic consistency, enabling us to model the time-dependent, large strain response of elastomers and predict the Payne effect in filled rubber. This effect, characterized by deformation-enhanced shear thinning, poses unique modeling challenges. Additionally, we discuss data augmentation procedures to address the data-intensive nature of training neural networks, showcasing the effectiveness of utilizing ordinary dynamic mechanical analysis (DMA) tests for this purpose.

将非弹性本构方程纳入有限元软件的一种既定方法是使用流变单元，串联或并联组装，以描述每个材料点的本构响应。这种方法可以通过利用变形梯度的乘法分解扩展到有限应变。在这项研究中，我们提出了一种混合方法，将传统元素与元素结合起来，通过深度神经网络（dnn）定义本构方程，成为标准流变元素的组合。我们制定dnn以保证热力学一致性，使我们能够模拟弹性体的时间依赖性大应变响应，并预测填充橡胶中的Payne效应。这种以变形增强剪切变薄为特征的效应，对建模提出了独特的挑战。此外，我们讨论了数据增强程序，以解决训练神经网络的数据密集型性质，展示了为此目的利用普通动态力学分析（DMA）测试的有效性。

引用次数: 0

Achieving geometric accuracy in FFT-based micromechanical models using conformal grid 利用保形网格实现基于fft的微力学模型的几何精度

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

Mechanics of Materials

Pub Date : 2026-01-01 Epub Date: 2025-10-01 DOI: 10.1016/j.mechmat.2025.105512

Miroslav Zecevic, Ricardo A. Lebensohn, Laurent Capolungo

Owing to its efficiency, simplicity and robustness, the FFT-based method has become the standard for computation of mechanical fields in a heterogeneous periodic unit cell. One of the main disadvantages of the FFT-based method is the inaccurate representation of the initial microstructure on a regular grid of voxels, which can be alleviated through the use of distorted initial grids. In this paper, a method for generation of distorted initial grids conforming to the microstructural features (e.g. straight/curved boundaries) is proposed. The method determines the positions of the grid nodes in the initial configuration by solving a system of springs connecting the nodes. Microstructures consisting of layers, Voronoi tessellation and circular/spherical inclusions are considered, and mechanical fields simulated using the FFT-based method. It is found that distorted initial grids, conforming to the microstructural features, lead to more accurate mechanical fields in comparison to the corresponding non-distorted initial grid solution. The effect of initial grid distortion on the convergence of the FFT-based method is analyzed and discussed.

基于fft的方法由于其高效、简单和鲁棒性，已成为计算非均匀周期单元胞中力学场的标准方法。基于fft的方法的主要缺点之一是初始微观结构在规则体素网格上的不准确表示，可以通过使用扭曲的初始网格来缓解这一问题。本文提出了一种生成符合微观结构特征（如直/弯边界）的畸变初始网格的方法。该方法通过求解连接节点的弹簧系统来确定网格节点在初始构型中的位置。考虑了由层、Voronoi镶嵌和圆形/球形夹杂组成的微观结构，并使用基于fft的方法模拟了力学场。结果表明，与非畸变初始网格解相比，畸变初始网格解得到的力学场更为精确，且符合微观结构特征。分析和讨论了初始网格畸变对基于fft的方法收敛性的影响。

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引用次数: 0