European Journal of Mechanics A-Solids最新文献_第6页

Fracture mechanism in SUS304 during small punch tests SUS304的小冲孔断裂机理

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-24 DOI: 10.1016/j.euromechsol.2025.105953

Chong Gao , Yihui Huang , Qian Sun , Bo Cao , Takeshi Iwamoto , Tsutomu Umeda , Takayuki Kusaka

Past experimental result reveals that a region of the fracture initiation in metastable austenitic stainless steel SUS 304 during a small punch test changes from the loading side to free surface with respect to the loading rate. Since a measurement of a time series of the martensite and temperature distribution, which strongly affects the fracture behavior, is difficult to be realized during testing, a precise finite element (FE) analysis is necessary to support further discussions on the mechanism of the loading rate sensitivity. In the current work, the phenomena observed in the tests are precisely reproduced through the FE analyses including the martensitic transformation and the damage evolution modelled by authors. The condition for the onset of crack extension is provided to assist the future works in determining where the initiation occurs. Even though the austenitic phase is dominant for the fracture, a larger damage variable appears in the region where a significant quantity of martensite is distributed. Simultaneously, the work clarifies the influence of reducing the amount of martensite with respect to the loading rate on ductility of the material. In the dynamic loading, it is newly discovered that the thermal softening plays an important role, inducing the fracture from the free surface of the specimen.

以往的实验结果表明，在小冲孔试验中，亚稳奥氏体不锈钢sus304的断裂起始区域随加载速率从加载侧向自由表面变化。由于在试验过程中难以测量对断裂行为有强烈影响的马氏体和温度分布的时间序列，因此有必要进行精确的有限元分析，以支持进一步讨论加载速率敏感性的机制。在本工作中，通过有限元分析，包括马氏体相变和作者模拟的损伤演化，精确地再现了试验中观察到的现象。提供了裂纹扩展开始的条件，以协助今后的工作确定裂纹扩展开始的位置。尽管奥氏体相在断裂中占主导地位，但在大量分布马氏体的区域出现较大的损伤变量。同时，阐明了相对于加载速率减少马氏体含量对材料延展性的影响。在动加载过程中，新发现热软化起着重要的作用，从试件自由表面诱发断裂。

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引用次数: 0

Development of a Lagrange multiplier/cohesive zone approach for dynamic internal-interfacial crack interactions in laminated structures 基于拉格朗日乘子/内聚区方法的层合结构内部-界面裂纹动态相互作用研究

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-24 DOI: 10.1016/j.euromechsol.2025.105951

Yifang Qin , Shunhua Chen , Mitsuteru Asai

The main purpose of this work is to develop a nodal-based Lagrange multiplier/cohesive zone (LM/CZ) approach for accurate simulations of internal-interfacial crack interactions in laminated structures. The appeal of the presented approach lies in dealing with crack interactions in a natural and simple way, while inheriting the advantages of addressing the so-called artificial compliance issue and allowing for the use of non-matching meshes between structure layers. To achieve the end, the developed approach introduces the LM method to accurately enforce the continuity across nodes, and adopts a shifted traction separation law (TSL) to govern the subsequent cohesive crack behaviors. Internal and interfacial nodal groups are constructed, and the concept of ghost points is introduced to facilitate interfacial crack simulations with both matching and non-matching meshes in a unified way. Special attention is given to crack message transmission to effectively account for internal-interfacial crack interactions. The accuracy and effectiveness of the developed approach are demonstrated via benchmark examples. Finally, the capacity of the presented approach is further explored by extending the applications to crack interactions of two- and three-fiber/matrix units. Results show that our approach can effectively simulate complex crack interactions, including internal crack-induced interfacial crack as well as interfacial debonding triggered by internal cracks.

本工作的主要目的是开发一种基于节点的拉格朗日乘子/内聚区（LM/CZ）方法，用于精确模拟层合结构中内部-界面裂纹相互作用。所提出的方法的吸引力在于以自然和简单的方式处理裂缝相互作用，同时继承了解决所谓的人工顺应性问题和允许在结构层之间使用不匹配网格的优点。为了实现这一目标，该方法引入了LM方法来精确执行节点间的连续性，并采用了位移牵引分离律（TSL）来控制后续的内聚裂纹行为。构造内部节点群和界面节点群，引入虚点的概念，便于统一模拟匹配网格和非匹配网格的界面裂缝。特别注意裂缝信息的传输，以有效地解释内部-界面裂缝相互作用。通过基准算例验证了该方法的准确性和有效性。最后，通过扩展应用于两根和三根纤维/矩阵单元的裂纹相互作用，进一步探讨了所提出方法的能力。结果表明，该方法可以有效地模拟复杂的裂纹相互作用，包括内部裂纹引起的界面裂纹以及由内部裂纹引发的界面剥离。

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引用次数: 0

Corrigendum to “Hyperelastic nature of the Hoek–Brown criterion” [Europe. J. Mech. A/Solid. 115 (2026) 105782] “Hoek-Brown准则的超弹性性质”的勘误表[欧洲]。j .机械工程。A /固体。115 (2026) 105782]

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-23 DOI: 10.1016/j.euromechsol.2025.105945

I. Fontana , G. Bacquaert , D.A. Di Pietro , K. Kazymyrenko

引用次数: 0

Performance of nonlinear piezoelectric energy harvesting systems based on shear deformable beam theories 基于剪切变形梁理论的非线性压电能量收集系统性能研究

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-22 DOI: 10.1016/j.euromechsol.2025.105958

Guanghui Xia , Mingrui Liu , Yufeng Zhang , Jun Yin , Xiaofang Kang , Tingting Han , Leiyu Chen , Weiqiu Chen , C.W. Lim

Based on shear deformable beam models and Hamilton's principle, the governing equations considering geometric, inertial, and electromechanical coupling nonlinearity effects are established and solved. The nonlinear partial differential equations are decoupled and reduced to a lower-order form via the Galerkin method. The technique of multiple scales is then applied to derive the approximate analytical solutions. Subsequently, analytical formulations for vibration displacement, harvested voltage, and electrical power output are established. Based on Timoshenko Beam Model (TM) and Euler-Bernoulli Beam Model (EBM), this study examines how excitation intensity, damping properties, external resistance, and tip mass influence the amplitude-frequency characteristics and stability of energy harvesters with varying length-to-thickness ratios. The results indicate that for structures with a low length-to-thickness ratio, the TM yields more accurate computational solutions. Furthermore, appropriate adjustment of the damping properties and external resistance enhances the stability of energy harvesting performance under low-frequency resonance, thereby augmenting the power conversion capability of resonant piezoelectric harvesters.

基于剪切变形梁模型和Hamilton原理，建立并求解了考虑几何、惯性和机电耦合非线性效应的控制方程。利用伽辽金方法将非线性偏微分方程解耦并简化为低阶形式。然后应用多尺度技术求出近似解析解。随后，建立了振动位移、收获电压和电力输出的解析公式。基于Timoshenko梁模型（TM）和Euler-Bernoulli梁模型（EBM），本研究考察了激励强度、阻尼特性、外部电阻和尖端质量如何影响不同长厚比的能量采集器的幅频特性和稳定性。结果表明，对于长厚比较低的结构，TM的计算结果更为精确。此外，适当调整阻尼特性和外电阻，提高了低频谐振下能量收集性能的稳定性，从而提高了谐振式压电采集器的功率转换能力。

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引用次数: 0

Influence of heat treatment on microstructure and mixed-mode fracture behaviour of additively manufactured 316L stainless steel 热处理对增材制造316L不锈钢组织及混合模式断裂行为的影响

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-21 DOI: 10.1016/j.euromechsol.2025.105949

Cansin Ozdogan , Rasid A. Yildiz , Luciana Tavares , Ozkan Gokcekaya , Mohammad Malekan

Additive manufacturing (AM) has significant advantages over traditional production methods, including reduced material waste and enhanced design freedom. One of the dominant AM processes, laser powder bed fusion (L-PBF), relies on important process parameters—scanning speed, layer thickness, and laser power—whose settings determine the microstructure and mechanical properties of L-PBF-printed parts. In this study, correlation of microstructure and macro-mechanical fracture behaviour of L-PBF-printed 316L stainless steel material is investigated. It also contains comparison of as-built and heat-treated specimens at 700 °C, 900 °C, and 1100 °C on force-displacement curves and microstructure. Arcan fixture was employed to analyse mixed-mode fracture behaviour, and microstructural examination of fracture surfaces uses scanning electron microscopy, X-ray diffractometer, and electron backscatter diffraction. Apart from that, Johnson Cook plasticity theory was applied to as-built Arcan specimens under pure shear, mixed mode, and tensile loadings with Abaqus/CAE software. Influence of porosity in mechanical behaviour was sought on comparing experimental and numerical results. As a result, numerical results were extremely in line with experiments. The findings provide a correlation of micro-scale properties, fracture properties, and L-PBF process parameters and provide insights on the optimization of AM component design and performance.

与传统的生产方法相比，增材制造（AM）具有显著的优势，包括减少材料浪费和提高设计自由度。作为主流增材制造工艺之一，激光粉末床熔融（L-PBF）依赖于重要的工艺参数——扫描速度、层厚度和激光功率，这些参数的设置决定了L-PBF打印件的微观结构和力学性能。研究了l - pbf打印316L不锈钢材料的微观组织与宏观力学断裂行为的相关性。它还包含了在700°C， 900°C和1100°C的力-位移曲线和微观结构上的构建和热处理样品的比较。使用Arcan夹具分析混合模式断裂行为，并使用扫描电镜、x射线衍射仪和电子背散射衍射对断口表面进行微观结构检查。此外，利用Abaqus/CAE软件，将Johnson Cook塑性理论应用于Arcan试件在纯剪切、混合模式和拉伸载荷下的原状。通过对实验结果和数值结果的比较，寻求孔隙率对力学行为的影响。结果表明，数值计算结果与实验结果非常吻合。研究结果提供了微尺度性能、断裂性能和L-PBF工艺参数之间的相关性，并为增材制造部件的设计和性能优化提供了见解。

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引用次数: 0

Nonlinear oscillations and chaotic behavior of sandwich cylindrical shells with auxetic core and FG face sheets 带辅助芯和FG面板夹层圆柱壳的非线性振动和混沌行为

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-21 DOI: 10.1016/j.euromechsol.2025.105955

Soheil Hashemi , Amin Rezaeezadeh

Auxetic materials are novel substances that create significant research opportunities for scientists due to their negative Poisson's ratio. This study presents an analysis of the nonlinear forced vibrations and chaotic behavior of auxetic-core sandwich cylindrical shells (AXC-SCSs) with functionally graded (FG) skins subjected to harmonic loading. To achieve this, the governing equations of the system are derived using first-order shear deformation theory (FSDT) and the von Karman relations. The displacement field is expressed in terms of 24 generalized coordinates corresponding to the driven, companion, and axisymmetric modes of simply supported shells. Subsequently, the multi-mode Galerkin and static condensation methods are applied to convert the partial differential equations into a set of four-degree-of-freedom nonlinear ordinary differential equations. Finally, the nonlinear four-degree-of-freedom equations are solved analytically using the multiple-time-scale method. The main novelty of this research lies in the incorporation of strong nonlinear coupling between driven and companion modes in the AXC-SCS, enabling a precise prediction of nonlinear oscillation behaviors. In the results section, the obtained findings are verified by comparison with previously published studies and numerical solutions. Finally, the effects of system parameters on the nonlinear frequency response, time history, phase-plane, and bifurcation diagrams are studied. The findings reveal that an increase in the inclined rib angle (θ) and the cell thickness-to-inclined rib length ratio (t/l), along with a decrease in the horizontal-to-inclined rib length ratio (w/l), enhances the hardening behavior and narrows the resonance region of the shell. However, when the companion mode is included, these trends are reversed. Time-history analyses show that increasing θ and t/l, and decreasing w/l, reduce the vibration amplitude. The proposed analytical framework provides a reliable and efficient tool for predicting and controlling nonlinear dynamic responses in a sandwich shell with an auxetic structure.

补充材料是一种新型物质，由于其负泊松比，为科学家创造了重要的研究机会。本文研究了具有功能梯度（FG）蒙皮的外源芯夹层圆柱壳（axc - scs）在谐波荷载作用下的非线性强迫振动和混沌行为。为此，利用一阶剪切变形理论（FSDT）和von Karman关系推导了系统的控制方程。位移场用24个广义坐标表示，对应于简支壳的驱动模态、伴模态和轴对称模态。然后，采用多模伽辽金和静态凝聚方法将偏微分方程转化为一组四自由度非线性常微分方程。最后，采用多时间尺度法对非线性四自由度方程进行解析求解。该研究的主要新颖之处在于在AXC-SCS中加入了驱动模式和伴随模式之间的强非线性耦合，从而能够精确预测非线性振荡行为。在结果部分，通过与先前发表的研究和数值解的比较，验证了所获得的发现。最后，研究了系统参数对非线性频率响应、时程、相平面和分岔图的影响。结果表明：斜肋角（θ）和单元厚度与斜肋长比（t/l）的增大，水平与斜肋长比（w/l）的减小，增强了壳体的硬化性能，缩小了壳体的共振区；然而，当包括伴侣模式时，这些趋势就会逆转。时程分析表明，增大θ和t/l，减小w/l，振动幅值减小。所提出的分析框架为预测和控制夹层结构的非线性动力响应提供了可靠和有效的工具。

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引用次数: 0

Deep learning based inverse design of metamaterials for vibration control 基于深度学习的超材料振动控制逆设计

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-21 DOI: 10.1016/j.euromechsol.2025.105957

Chunfeng Zhao , Tian Zhang , Ao Huang , Qiaoyun Wu , Zhenyu Chen

Multi-source vibration control is of great importance to human comfort and the built environment, and metamaterials offer an efficient pathway for low-frequency vibration control. However, traditional metamaterial design approaches are often limited by computational efficiency and empirically guided iterative optimization processes. In this study, we present an inverse design methodology for metamaterials that utilizes deep learning models to achieve target bandgap characteristics and transmission loss specifications. The metamaterials are initially parameterized using parametric Bezier curves, and the unit-cell image is downscaled with an encoder from the variational autoencoder (VAE) model. Two inverted transformer (iTransformer) models are trained to predict the dispersion relations and transmission loss curves using the data obtained from the finite element method (FEM), respectively. An iTransformer-VAE-guided genetic algorithm is subsequently employed to inversely generate the geometrical parameters of the metamaterials by specifying the target bandgap and transmission loss profiles. Finally, metamaterials designed using this approach exhibit varying bandgaps and transmission losses, which are then validated against numerical and experimental results. The results indicate that a relative bandgap width error of 1.97 % and an average transmission loss error of 10.83 % for the inversely design metamaterials. Time history analysis and experimental validation further reveal that the proposed metamaterials can attenuate vibration waves by up to 96.09 % when the dominant frequency lies within the bandgap ranges. This study can provide a valuable reference for both transmission characteristics prediction and inverse design of metamaterials.

多源振动控制对人体舒适性和建筑环境具有重要意义，而超材料为低频振动控制提供了有效途径。然而，传统的超材料设计方法往往受到计算效率和经验指导迭代优化过程的限制。在这项研究中，我们提出了一种利用深度学习模型来实现目标带隙特性和传输损耗规格的超材料逆设计方法。超材料最初使用参数化贝塞尔曲线进行参数化，并使用变分自编码器（VAE）模型的编码器对单位细胞图像进行缩小。利用有限元法得到的数据，分别训练了两个逆变变压器模型来预测频散关系和传输损耗曲线。随后，通过指定目标带隙和传输损耗曲线，采用ittransformer - vee引导的遗传算法反向生成超材料的几何参数。最后，使用这种方法设计的超材料表现出不同的带隙和传输损耗，然后根据数值和实验结果进行验证。结果表明，反向设计的超材料的相对带隙宽度误差为1.97%，平均传输损耗误差为10.83%。时程分析和实验验证进一步表明，当主导频率在带隙范围内时，所提出的超材料对振动波的衰减率高达96.09%。该研究可为超材料的传输特性预测和逆向设计提供有价值的参考。

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引用次数: 0

Towards the exploration of self-starting single-solve integration algorithms with third-order accuracy for nonlinear dynamics 非线性动力学三阶精度自启动单解积分算法的探索

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-19 DOI: 10.1016/j.euromechsol.2025.105954

Yaokun Liu, Jinze Li, Kaiping Yu

The single-step explicit time integration methods have long been valuable for solving large-scale nonlinear dynamic problems, classified into single-solve and multi-sub-step approaches. However, no existing conventional single-solve methods achieve third-order accuracy in any primary variables (displacement, velocity or acceleration). The paper addresses this gap by the framework of conventional self-starting single-solve time integration algorithms, which incorporates eleven algorithmic parameters. The study reveals that self-starting single-solve explicit methods cannot reach third-order accuracy in any primary variables for solving damped problems. Consequently, two novel algorithms are proposed: Algorithm 1 is an explicit scheme that achieves third-order accuracy in displacement and velocity undamped problems; Algorithm 2 is an implicit scheme which degenerates to an explicit scheme when solving the undamped problems, and it achieves third-order accuracy in displacement and velocity for any damped problems. Across a suite of both linear and nonlinear benchmarks, the new algorithms consistently outperform existing conventional explicit methods in accuracy. Their built-in numerical dissipation effectively filters out spurious high-frequency components, as demonstrated by two wave propagation problems. Finally, when applied to the realistic engineering problem, both of them deliver superior numerical precision at a reasonable computational cost.

单步显式时间积分法在求解大规模非线性动力问题方面一直具有重要的应用价值，可分为单步法和多子步法。然而，现有的常规单次求解方法在任何主要变量（位移、速度或加速度）上都无法达到三阶精度。本文通过传统的自启动单解时间积分算法框架解决了这一缺陷，该算法包含11个算法参数。研究表明，自启动单解显式方法在求解阻尼问题时，在任何主变量上都不能达到三阶精度。因此，提出了两种新的算法：算法1是一种显式格式，在位移和速度无阻尼问题中达到三阶精度；算法2是一种隐式格式，在求解无阻尼问题时退化为显式格式，对于任何有阻尼问题，它在位移和速度上都能达到三阶精度。在一系列线性和非线性基准测试中，新算法在精度上始终优于现有的传统显式方法。其内置的数值耗散有效地滤除了杂散高频分量，正如两个波传播问题所证明的那样。最后，当应用于实际工程问题时，两者都以合理的计算成本提供了较高的数值精度。

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引用次数: 0

3D star-shaped lattice metamaterials exhibiting zero Poisson's ratio 零泊松比的三维星形晶格超材料

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-19 DOI: 10.1016/j.euromechsol.2025.105952

Luke Mizzi, Alexandre Périer

Zero Poisson's ratio metamaterials are a peculiar class of metamaterial systems which undergo no lateral deformation upon uniaxial loading. In this work, we propose a new 3D star-shaped lattice metamaterial structure which is specifically designed to exhibit this property in all three principal directions. This system, which is highly anisotropic, can have a tailorable stiffness which is dependent on the geometry of the structure and may be altered according to design specifications without influencing the Poisson's ratio. An analytical model which may be used to predict the mechanical properties of this system was derived and validated through a wide ranging parametric Finite Element simulation run. In addition, a prototype system was produced using additive manufacturing and tested under compressive loading, with Digital Image Correlation techniques confirming the zero Poisson's ratio of the system, which is retained under relatively high-strain loading. It is envisaged that the large versatility and tuneability of this new metamaterial structure make it ideal for future implementation in applications requiring zero Poisson's ratio properties.

零泊松比超材料是一类特殊的在单轴载荷作用下不发生侧向变形的超材料体系。在这项工作中，我们提出了一种新的3D星形晶格超材料结构，该结构专门设计用于在所有三个主要方向上表现出这种特性。该系统具有高度的各向异性，可以根据结构的几何形状定制刚度，并且可以根据设计规范进行更改，而不会影响泊松比。推导了可用于预测该系统力学性能的解析模型，并通过大范围参数有限元仿真运行进行了验证。此外，使用增材制造技术制作了一个原型系统，并在压缩载荷下进行了测试，使用数字图像相关技术确认了系统的零泊松比，该泊松比在相对高应变载荷下保持不变。据设想，这种新的超材料结构的大通用性和可调性使其成为未来在需要零泊松比特性的应用中实现的理想选择。

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引用次数: 0

Unified model of rub-impact vibration response of high-low pressure double-rotor-SFD-intermediate bearing system of aero-engine under typical maneuvering loads 典型机动载荷下航空发动机高低压双转子- sfd -中间轴承系统碰摩振动响应统一模型

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2025-11-19 DOI: 10.1016/j.euromechsol.2025.105948

Wujiu Pan , Yuting Liu , Qilong Wu , Wenxin Wang , Junyi Wang

Dual-rotor aero-engines are widely used in the field of aero-engines, with their outer and inner rotors coupled via an intermediate bearing. The coupling characteristics introduced by the intermediate bearing increase the complexity of the system's dynamic properties, making it necessary to analyze the different nonlinear dynamic behaviors of the dual-rotor system under typical maneuvering conditions. Based on finite element theory, a model of a 10-node diameter shaft double rotor system with SFD-intermediate bearings was established under three typical maneuvering conditions. The model includes the oil film force, the nonlinear Hertzian contact force, the blade-casing rub-impact force, the gravitational field, the rotor eccentric imbalance force, and typical maneuvering loads. The correctness of the present theoretical modeling method was verified by comparing it with the ANSYS modeling method. The Newmark-β method was used to solve the 10-node-diameter shaft model. The system's blade-casing rub-impact response under different maneuvering loads and different rotor speed ratios was analyzed, and the system response characteristics under three maneuvering flight conditions were compared and analyzed. Research has found that under the same dynamic load or speed ratio conditions, the possibility of blade-casing rub-impact between dual rotor systems under different dynamic conditions varies.

双转子航空发动机是一种广泛应用于航空发动机领域的发动机，其内外转子通过中间轴承耦合。中间轴承引入的耦合特性增加了系统动态特性的复杂性，因此有必要对典型机动工况下双转子系统的不同非线性动态行为进行分析。基于有限元理论，建立了含sfd -中间轴承的10节直径轴双转子系统在三种典型机动工况下的模型。该模型包括油膜力、非线性赫兹接触力、叶片-机匣摩擦-撞击力、引力场、转子偏心不平衡力和典型机动载荷。通过与ANSYS建模方法的比较，验证了该理论建模方法的正确性。采用Newmark-β方法求解10节径轴模型。分析了系统在不同机动载荷和不同旋翼速比下的叶片-机匣摩碰响应，对比分析了系统在三种机动飞行工况下的响应特性。研究发现，在相同动载荷或速比条件下，不同动态条件下双转子系统发生叶片-机匣碰摩的可能性是不同的。

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引用次数: 0