Mechanics of Materials最新文献_第6页

A grain boundary region model to capture grain size and misorientation effects on elasto-plastic response of polycrystals 一个晶界区域模型来捕捉晶粒尺寸和取向错误对多晶弹塑性响应的影响

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-11-11 DOI: 10.1016/j.mechmat.2025.105541

Devesh Tiwari , Ayub Khan , Pierre-Antony Deschênes , Daniel Paquet , Pritam Chakraborty

Grain Boundaries (GBs) disrupt the motion of dislocations and thereby affect the elasto-plastic deformation behavior of polycrystalline alloys. A majority of conventional polycrystal plasticity models represent GBs as sharp interfaces and do not incorporate GB micro-mechanics. In this work, a novel constitutive formulation for finitely thick GB region is developed which incorporates properties of all the adjoining grains. The GB model is based on penalizing the slip rate on the slip systems of single crystals in the GB region with an extra activation energy term. The energy penalty is based on minimizing the remnant dislocation line on GB for incoming and outgoing slip systems and evolves with slip accumulation. The size dependent elasto-plastic response of polycrystals is captured in this model by incorporating Geometrically Necessary Dislocations (GNDs) in addition to the Statistically Stored Dislocations (SSDs). The model has been implemented in a Crystal Plasticity Finite Element Method (CPFEM) code and applied to simulate the plane strain uni-axial tensile deformation of FCC polycrystals. The analyses show that the model is able to capture: (i) the single crystal response for a bicrystal with zero misorientation; and (ii) the dependence of Hall–Petch factor on misorientation. A normalized critical GB thickness value has also been derived which renders the macroscopic response insensitive to the GB region size. Polycrystal CPFEM simulations demonstrate that the model can capture the strain dependence of Hall–Petch factor reasonably well.

晶界破坏位错的运动，从而影响多晶合金的弹塑性变形行为。大多数传统的多晶塑性模型将晶界表示为锐界面，而没有考虑晶界的微观力学。在这项工作中，开发了一个新的有限厚GB区域的本构公式，它包含了所有相邻晶粒的特性。GB模型是基于用一个额外的活化能项来惩罚GB区单晶滑移系统的滑移率。能量惩罚是基于最小化输入和输出滑移系统的残余位错线，并随着滑移积累而演变。该模型通过结合几何必要位错（GNDs）和统计存储位错（ssd）来捕获多晶体的尺寸相关弹塑性响应。该模型已在晶体塑性有限元（CPFEM）程序中实现，并应用于FCC多晶的平面应变单轴拉伸变形模拟。分析表明，该模型能够捕获：(1)零取向错的双晶体的单晶响应；(2)霍尔-佩奇因子对定向错误的依赖关系。我们还推导了一个归一化临界GB厚度值，使宏观响应对GB区域大小不敏感。多晶CPFEM仿真结果表明，该模型能较好地捕捉到Hall-Petch因子的应变依赖性。

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引用次数: 0

Effect of pore shape on steady plastic shockwaves and collapse dynamics in porous metals 多孔金属中孔隙形状对稳定塑性冲击波和坍塌动力学的影响

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-11-21 DOI: 10.1016/j.mechmat.2025.105551

Alain Molinari , Eyass Massarwa , Christophe Czarnota

Porous materials offer the possibility to optimize shock wave mitigation by monitoring, with additive manufacturing, the pore configuration (volume fraction, shape and spatial distribution of voids). Therefore, it is of interest to uncover the relationship between void configuration and shock wave response. In this paper we develop an analysis of planar plastic shock waves generated in porous aluminum by the impact of a projectile. Methodology and results can be easily extended to other materials. We focus specially on the relationship between shock-width and void-shape for given impact velocity and fixed initial volume fraction and spatial distribution of voids. We consider a Finite Element modeling of a periodic material with axisymmetric configuration. Each unit cell contains a spheroidal void with symmetry axis aligned along the impact direction. It is shown that the shock width is significantly affected by the process of void collapse. This process appears to be quite different for flat (oblate) and elongated (prolate) voids. For both types of voids, we analyze how the process and the speed of void closure are affected by the void aspect ratio, and we demonstrate that the shock width is increased by slowing down the speed of void collapse. Effects of the void aspect ratio on the void closure speed and on the shock-width are quantified. We explain why the slowest void closure and the largest shock width are obtained for spherical voids.

多孔材料可以通过增材制造技术监测孔隙结构（体积分数、形状和空间分布），从而优化冲击波缓解效果。因此，揭示空腔结构与激波响应之间的关系是很有意义的。本文研究了弹丸在多孔铝中产生的平面塑性激波。方法和结果可以很容易地扩展到其他材料。我们重点研究了在一定的冲击速度和固定的初始体积分数和空间分布条件下，激波宽度与孔洞形状的关系。考虑具有轴对称结构的周期性材料的有限元模型。每个单元格包含一个沿冲击方向对称轴对齐的球体空洞。结果表明，冲击宽度受空隙坍塌过程的显著影响。这一过程对于扁平（扁圆）和拉长（长形）的空洞来说是完全不同的。对于这两种类型的孔洞，我们分析了孔洞长径比对孔洞闭合过程和速度的影响，并证明了通过减缓孔洞坍塌的速度来增加激波宽度。定量分析了空腔长径比对空腔闭合速度和激波宽度的影响。我们解释了为什么最慢的空隙闭合和最大的激波宽度是由球形空隙获得的。

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引用次数: 0

A unified thermally activated viscoplastic framework for bitumen failure prediction across various loading paths 一个统一的热激活粘塑性框架，用于沥青在不同加载路径上的破坏预测

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-12-03 DOI: 10.1016/j.mechmat.2025.105569

Yankai Wen, Lin Wang

Accurately characterizing bitumen failure under combined thermal and mechanical stresses is key to designing durable pavement systems. This study proposes a unified, physically based framework that incorporates two thermally activated models to characterize the degradation behavior of bitumen. Eyring's stress-assisted molecular flow theory is applied to capture the nonlinear viscoplastic flow behavior under sustained loading, while a modified Arrhenius formulation expressed as a function of stress and temperature is utilized to mechanistically predict failure time. All model parameters are calibrated exclusively using constant-stress creep tests and are subsequently applied without any additional fitting to predict both the evolution of viscoplastic strain and the failure time under strain- and stress-controlled monotonic shear loading tests. Validation across a broad temperature spectrum confirms the model's high accuracy and indicates that viscoplastic deformation and failure are controlled by a common thermally activated mechanism, largely unaffected by the loading path. Minor deviations observed at elevated temperatures indicate the presence of self-healing behavior, suggesting a potential direction for future model refinement. Overall, the proposed framework provides a scalable, mechanistically interpretable, and experimentally efficient approach for reliable binder performance evaluation and performance-based material design.

准确表征沥青在热机械复合应力作用下的破坏是设计耐用路面系统的关键。本研究提出了一个统一的、基于物理的框架，该框架结合了两个热激活模型来表征沥青的降解行为。Eyring的应力辅助分子流动理论用于捕获持续载荷下的非线性粘塑性流动行为，而改进的Arrhenius公式表示为应力和温度的函数，用于机械地预测破坏时间。所有的模型参数都是用恒应力蠕变试验来校准的，然后在没有任何额外拟合的情况下应用，以预测在应变和应力控制的单调剪切加载试验下粘塑性应变的演变和破坏时间。广泛的温度谱验证证实了模型的高精度，并表明粘塑性变形和破坏是由一个共同的热激活机制控制的，在很大程度上不受加载路径的影响。在高温下观察到的微小偏差表明存在自我修复行为，这为未来模型的改进提供了一个潜在的方向。总的来说，所提出的框架为可靠的粘合剂性能评估和基于性能的材料设计提供了一种可扩展的、机械上可解释的、实验上有效的方法。

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引用次数: 0

A failure mode dependent damage model with analytical expressions of damage evolution for brittle fiber reinforced composites 基于破坏模式的脆性纤维增强复合材料损伤演化解析模型

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-11-27 DOI: 10.1016/j.mechmat.2025.105562

Shubham Rai, Badri Prasad Patel

A 3D failure mode dependent continuum damage model is proposed for brittle fiber-reinforced laminated composites with analytical expressions for coupled damage evolution equations. Two strategies are used to determine coupling vectors (responsible for coupling of damage evolution in different directions): (1) derived from potential functions, and (2) determined from uniaxial and shear experimental stress–strain data. The damage model parameters are determined by minimizing the difference between model predicted and available experimental uniaxial and shear stress–strain curves in the literature. The proposed model captures varying degree of non-linearity in available experimental uniaxial and shear stress–strain curves. The calibrated damage model is employed for progressive failure analysis of moderately thick laminated composite plates using higher-order shear deformation theory with thickness stretch and zig-zag terms. The governing equations are solved using finite element method coupled with Newton–Raphson iterative procedure. It is found that the damage variables based on coupling vectors derived from potential functions are physically consistent unlike coupling vectors obtained from uniaxial and shear stress–strain curves. The proposed model predicts different damage in tension and compression consistent with the strength properties of fiber reinforced composite material in different directions. A parametric study demonstrates the model’s flexibility to match failure loads predicted by existing models in the literature. The model predicted failure loads for notched laminated composite plates under uniaxial tension show good agreement with the experimental results available in the literature.

提出了一种依赖于三维破坏模式的脆性纤维增强层合复合材料连续损伤模型，并给出了耦合损伤演化方程的解析表达式。确定耦合向量（负责不同方向损伤演化的耦合）采用两种策略：(1)由势函数推导，(2)由单轴和剪切实验应力-应变数据确定。损伤模型参数的确定是通过最小化模型预测和现有实验单轴和剪切应力-应变曲线之间的差异来确定的。该模型捕获了现有的单轴和剪切应力-应变曲线的不同程度的非线性。采用校正后的损伤模型，采用高阶剪切变形理论对中厚复合材料层合板的递进破坏进行了分析。采用有限元法结合牛顿-拉夫森迭代法求解控制方程。结果表明，基于势函数的耦合向量的损伤变量与单轴应力-应变曲线和剪切应力-应变曲线的耦合向量在物理上是一致的。该模型在不同方向上预测了与纤维增强复合材料强度特性相一致的拉伸和压缩损伤。参数研究表明，该模型的灵活性，以匹配失效载荷预测现有的模型在文献中。该模型预测的缺口层合板在单轴拉伸作用下的破坏载荷与文献试验结果吻合较好。

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引用次数: 0

Characterizing friction coefficients of soft materials via stick-slip data in static friction: Mechanism analysis and experimental validation 用静摩擦黏滑数据表征软质材料摩擦系数：机理分析与实验验证

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-11-10 DOI: 10.1016/j.mechmat.2025.105545

Huixin Wei , Wei Fang , Shibin Wang , Zhiyong Wang , Zehui Lin , Baopeng Liao

Understanding the friction behavior of soft materials critically depends on the precise characterization of the contact interface. The current characterization methods of friction behavior are limited by its predominant reliance on data from the sliding stage, which often neglects the static friction. In this study, a friction model describing the static friction stage of soft materials is proposed, considering contact deformation and stick slip phenomena. A tribometry platform is designed to investigate these interfacial phenomena during soft material friction. The platform integrates an optical visualization setup with high-resolution imaging components and mechanical loading systems, enabling real-time monitoring of contact evolution. An automated image processing algorithm with edge detection is developed to quantitatively extract displacement-dependent contact zone boundaries from the captured image sequences. Full-field displacement mapping within the contact zone is achieved through integration with two-dimensional digital image correlation (2D-DIC) analysis. The friction coefficient can be further determined by friction model and stick-slip data in static friction. The developed methodology provides new insights into interfacial mechanisms and a characterization framework for sliding friction of soft material, with the applicability in evaluating grip performance of robotics.

理解软质材料的摩擦行为关键取决于接触界面的精确表征。目前的摩擦行为表征方法主要依赖于滑动阶段的数据，往往忽略了静摩擦。本文提出了一种描述软质材料静摩擦阶段的摩擦模型，考虑了接触变形和粘滑现象。设计了一个摩擦测量平台来研究软质材料摩擦过程中的这些界面现象。该平台集成了光学可视化设置、高分辨率成像组件和机械加载系统，能够实时监测接触演变。提出了一种带有边缘检测的自动图像处理算法，从捕获的图像序列中定量提取与位移相关的接触区边界。通过与二维数字图像相关（2D-DIC）分析相结合，实现了接触区内的全场位移映射。通过静摩擦时的摩擦模型和粘滑数据可以进一步确定摩擦系数。所开发的方法为软质材料滑动摩擦的界面机制和表征框架提供了新的见解，具有评估机器人抓取性能的适用性。

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引用次数: 0

A multi-layer model for residual stress relaxation aligned with microstructure evolution under thermal exposure and cyclic loading 基于热暴露和循环加载下微观结构演变的残余应力松弛多层模型

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-11-07 DOI: 10.1016/j.mechmat.2025.105543

Dianyin Hu , Tao Wang , Hongyang Huang , Jianxing Mao , Jier Wang , Xin Wang , Yang Gao , Liucheng Zhou , Rongqiao Wang

Residual stress relaxation phenomena under thermomechanical conditions, particularly thermal exposure and cyclic loading, constitute critical determinants of fatigue performance in surface-treated engineering components. This study systematically investigates the thermal and cyclic relaxation mechanisms in shot-peened Ni-based superalloy GH4720Li through integrated experimental characterization and computational modeling. Through systematic characterization via X-ray diffraction (XRD) and electron backscatter diffraction (EBSD), we establish quantitative correlations between residual stress relaxation kinetics and concurrent microstructure evolution, particularly dislocation annihilation and grain boundary restructuring. Building upon these observations, a novel multilayer constitutive framework is developed to decouple the synergistic effects of microstructural evolution on residual stress relaxation dynamics. The model demonstrates predictive accuracy within 6.3 % for residual stress magnitudes and 3.3 % for characteristic depth parameters when compared to stabilized thermal exposure data. Under cyclic loading conditions, corresponding errors remain constrained to 15.5 % and 4.8 %, respectively. Such precision validates the model's capability to isolate microstructure-driven relaxation mechanisms from purely mechanical contributions. This multi-physics framework provides an unprecedented quantitative tool for optimizing surface-engineered components operating in combined high-temperature and cyclic loading environments, effectively bridging the gap between microstructure-aware modeling and industrial fatigue life prediction.

热机械条件下的残余应力松弛现象，特别是热暴露和循环加载，是表面处理工程部件疲劳性能的关键决定因素。本研究通过实验表征和计算建模相结合的方法，系统地研究了喷丸ni基高温合金GH4720Li的热弛豫机制和循环弛豫机制。通过x射线衍射（XRD）和电子背散射衍射（EBSD）的系统表征，我们建立了残余应力松弛动力学与同步微观结构演化，特别是位错湮灭和晶界重构之间的定量相关性。在这些观察的基础上，开发了一种新的多层本构框架，以解耦微观结构演化对残余应力松弛动力学的协同效应。与稳定的热暴露数据相比，该模型对残余应力值的预测精度在6.3%以内，对特征深度参数的预测精度在3.3%以内。在循环加载条件下，相应的误差分别被限制在15.5%和4.8%。这样的精度验证了该模型将微观结构驱动的松弛机制与纯粹的力学贡献分离开来的能力。这种多物理场框架提供了一种前所未有的定量工具，用于优化在高温和循环加载环境下运行的表面工程部件，有效地弥合了微结构感知建模和工业疲劳寿命预测之间的差距。

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引用次数: 0

A unified treatment of two-dimensional adhesive contact on a power-law graded elastic half-plane 幂律梯度弹性半平面上二维粘着接触的统一处理

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-11-25 DOI: 10.1016/j.mechmat.2025.105559

Fan Xia , Fan Jin

This study develops a unified theoretical solution for two-dimensional (2D) adhesive contact between a power-law graded elastic half-plane and symmetric rigid punches, covering both JKR-type adhesive and non-adhesive conditions. Based on the Betti reciprocal theorem and the generalized Abel transform, closed-form expressions are obtained for surface deformation, pressure distribution, load-displacement relations, and pull-off force. The solution is applied to analyze various punch profiles, such as power-law, cylindrical, optimal, and concave types, highlighting the coupled effects of punch geometry and material gradation on debonding behavior. Classical results for flat, parabolic, and wedge indenters are recovered as special cases. Notably, only the wedge punch exhibits a pull-off force independent of Young’s modulus and Poisson’s ratio in the 2D case, in contrast with the axisymmetric case where only the parabolic punch shows such behavior. For concave indenters, three debonding modes (from edge, center, or full-interface) can be controlled via geometric or gradation parameters. These results provide insights for designing interfacial adhesion through coordinated geometric and material tailoring.

本研究为幂律梯度弹性半平面和对称刚性冲头之间的二维（2D）粘接接触提供了统一的理论解决方案，涵盖了jkr型粘接和非粘接条件。基于Betti互易定理和广义Abel变换，得到了曲面变形、压力分布、载荷-位移关系和拉拔力的封闭表达式。应用该方法分析了幂律型、圆柱型、最优型和凹型等冲孔轮廓，突出了冲孔几何形状和材料级配对脱粘行为的耦合影响。平面、抛物线和楔形压头的经典结果被恢复为特殊情况。值得注意的是，在二维情况下，只有楔形冲头表现出与杨氏模量和泊松比无关的拉离力，而在轴对称情况下，只有抛物线冲头表现出这种行为。对于凹压痕，可以通过几何或渐变参数控制三种剥离模式（从边缘、中心或全界面）。这些结果为通过协调几何和材料剪裁来设计界面粘附提供了见解。

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引用次数: 0

Semi-analytical method for frictional sliding contact of a piezoelectric layer-substrate 压电层-衬底摩擦滑动接触的半解析方法

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-12-10 DOI: 10.1016/j.mechmat.2025.105572

Van Thuong Nguyen , Van Son Pham , Nguyen Dinh Duc , Tinh Quoc Bui

Layer-substrate structures are commonly used in many high-tech devices and are often composed of anisotropic piezoelectric materials. Contact analysis of layer-substrate structures with accuracy and efficiency is vital in the design process to ensure the safety and performance of devices and systems. In this paper, we introduce a semi-analytical method (SAM) for fast and efficient analysis of frictional sliding contact in the piezoelectric layer-substrate structures. In this SAM setting, the surface Green function for a piezoelectric bimaterial is first derived. This Green’s function inherently satisfies the boundary conditions of the interfaces. Thus, SAM eliminates the need for meshing along the interface between the layer and substrate, which offers benefits in terms of meshing reduction, computational cost, and time. Using this Green’s function as a kernel, the SAM further benefits from analytically computable influence matrices, which boosts both accuracy and computational efficiency. The method is broadly applicable to systems in which the materials of the layer and substrate are generally anisotropic. The punch profile can be arbitrary and is either an insulator or a conductor. To verify the correctness of the proposed semi-analytical method, numerical results are compared to those obtained by the available methods, e.g., the analytical solutions and the boundary element method, and are verified through the mesh-sensitive analysis. With the numerical data, the parametric studies are implemented to demonstrate the versatility and explore the influences of the anisotropy, thickness of the layer, friction, and many other factors on the contact responses of the layer-substrate structures. These studies offer valuable insights for the design of smart layer-substrate structures that use anisotropic piezoelectric materials.

层-衬底结构通常用于许多高科技器件，通常由各向异性压电材料组成。准确、高效地对层-基板结构进行接触分析对于保证器件和系统的安全和性能至关重要。本文介绍了一种快速有效分析压电层-衬底结构摩擦滑动接触的半解析方法（SAM）。在此SAM设置下，首先推导了压电双材料的表面格林函数。该格林函数固有地满足界面的边界条件。因此，SAM消除了沿着层和基板之间的界面进行网格划分的需要，这在网格划分减少、计算成本和时间方面提供了好处。利用格林函数作为核，SAM进一步受益于解析可计算的影响矩阵，提高了精度和计算效率。该方法广泛适用于层和衬底材料一般各向异性的系统。冲孔轮廓可以是任意的，要么是绝缘体，要么是导体。为了验证所提出的半解析方法的正确性，将数值结果与解析解和边界元法等现有方法的结果进行了比较，并通过网格敏感分析进行了验证。利用数值数据，进行了参数化研究，以证明其通用性，并探讨了各向异性、层厚度、摩擦和许多其他因素对层-基底结构接触响应的影响。这些研究为使用各向异性压电材料的智能层-衬底结构的设计提供了有价值的见解。

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引用次数: 0

Global existence and uniqueness of weak solutions for a Willis-type model of elastodynamics 一类willis型弹性动力学模型弱解的整体存在唯一性

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-12-01 DOI: 10.1016/j.mechmat.2025.105561

Thomas Blesgen , Patrizio Neff

The existence and uniqueness of weak solutions is shown for a system related to the Willis model of elastodynamics. Both the whole space case and the case of a bounded smooth domain are studied. To this end the equations are reformulated as a linear symmetric hyperbolic system of first order and the existing theory for such systems is applied. If the initial and boundary data is regular enough, classical solutions are obtained. The possibility to transform the problem to a linear symmetric hyperbolic system hinges on a new symmetry condition on the Willis coupling tensor S, not yet considered in the literature. This condition demands that

S

is a totally symmetric third-order tensor.

研究了一类弹性动力学Willis模型系统弱解的存在唯一性。研究了整个空间和有界光滑域的情况。为此，将方程重新表述为一阶线性对称双曲系统，并应用已有的理论。如果初始数据和边界数据足够正则，则得到经典解。将问题转化为线性对称双曲系统的可能性取决于威利斯耦合张量S上的一个新的对称条件，这在文献中尚未考虑。这个条件要求S是一个完全对称的三阶张量。

引用次数: 0

Computational investigations of graded density metallic foams subjected to blast type loads 爆炸载荷作用下梯度密度金属泡沫材料的计算研究

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

Mechanics of Materials

Pub Date : 2026-02-01 Epub Date: 2025-12-09 DOI: 10.1016/j.mechmat.2025.105568

Bhanu Pratap Sharma, Abhijit Gogulapati, Viren Menezes

Foam-like materials are highly compressible and are widely used for shock and impact mitigation. However, studies show that under extreme loading, uniform-density Aluminum foams can amplify the incoming blast wave instead of attenuating it. The present work investigates the reasons behind such amplification using finite element simulations. The mitigation performance of Aluminum based uniform-density foams (UDFs) and graded-density foams (GDFs) were analyzed. The effects of various parameters such as peak pressure, foam density, foam length, pulse duration, and density gradient are presented. The gradient in density is introduced by using a Gaussian function. The ability of a given foam to mitigate or amplify a given load is examined with the help of the standard xt-plots and two non-dimensional parameters,

{\bar{P}}_{m a x}

and

\bar{l}

. The results show that based on the relative magnitudes of these parameters, the foam response falls into three regimes—elastic amplification, plastic attenuation, and plastic amplification. In particular, critical thresholds in length, pulse duration, peak pressure, and density gradient define the transition between amplification and attenuation. Neither UDFs nor GDFs are consistently superior; their performance depends on the interplay of the input parameters.

泡沫状材料具有高度可压缩性，广泛用于减轻冲击和冲击。然而，研究表明，在极端载荷下，均密度泡沫铝会放大而不是减弱来袭冲击波。本工作利用有限元模拟研究了这种放大背后的原因。分析了铝基均密度泡沫（UDFs）和梯度密度泡沫（GDFs）的减振性能。分析了峰值压力、泡沫密度、泡沫长度、脉冲持续时间和密度梯度等参数对泡沫的影响。利用高斯函数引入了密度梯度。给定泡沫减轻或放大给定载荷的能力通过标准x - t图和两个非维度参数P ‘ max和l ’来检查。结果表明：基于这些参数的相对量级，泡沫响应可分为弹性放大、塑性衰减和塑性放大三种状态；特别是，长度、脉冲持续时间、峰值压力和密度梯度的临界阈值定义了放大和衰减之间的过渡。udf和gdf都不是一贯的优越；它们的性能取决于输入参数的相互作用。

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引用次数: 0