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【新文速递】2025年1月17日固体力学SCI期刊最新文章

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今日更新:International Journal of Solids and Structures 1 篇,Journal of the Mechanics and Physics of Solids 2 篇,Thin-Walled Structures 4 篇

International Journal of Solids and Structures

Model for the onset of plasticity and hardness in bulk metallic glasses investigated by nanoindentation with a spherical indenter

Kai Tao, Xiao He, Hanwen Lu, Zhibo Zhang, Yong Yang, Eloi Pineda, Kaikai Song, Yiqiang He, Jichao Qiao

doi:10.1016/j.ijsolstr.2025.113238

球形压头纳米压痕法研究大块金属玻璃塑性和硬度的起始模型

Despite extensive research over the past three decades into how indentation depth affects the hardness (H) of both crystalline and non-crystalline materials, a mechanistic understanding of this phenomenon remains elusive. Here, we report that the depth dependence of H is also present in bulk metallic glasses. Importantly, indentation depth dependence is observed not only in hardness but also in the reduced elastic modulus Er. We observed that H initially increases with increasing indentation depth ht up to the yielding point. Beyond this point, however, it decreases with further increase of ht, indicating the presence of an indentation depth dependence in the plastic regions. The evolution of Er follows a similar trend. Based on our findings, firstly, we established the relationship between indentation hardness and the ratio of contact radius to indentation depth using classical Hertzian contact mechanics. Then, we developed a model based on the atomic-scale cooperative shear mechanism to interpret the indentation size effects in bulk metallic glasses. Furthermore, we observed that H correlates with the cube of the ratio of indentation elastic depth he to total depth ht, or alternatively, with the ratio of indentation elastic work to total work. Our findings gave a scaling law that uncovers an inherent relationship of hardness with the mean pressure at the onset of plasticity, flow hardness, and the ratio. The work underscores that the indentation depth effect stems from the interplay between elasticity and plasticity, rather than being solely influenced by factors like indentation depth, contact area, or indenter radius. This highlights its crucial role in comprehending and evaluating the plastic deformation of bulk metallic glasses at the submicron scale.

尽管过去三十年来对压痕深度如何影响晶体和非晶体材料的硬度(H)进行了广泛研究,但对其现象的机理理解仍不明确。在此,我们报告了在大块金属玻璃中也存在硬度(H)对压痕深度的依赖性。重要的是,这种压痕深度依赖性不仅在硬度上有所体现,在归一化弹性模量 Er 上也有观察到。我们发现,硬度 H 在压痕深度 ht 增加到屈服点之前会随其增加而增大,然而超过该点后,硬度 H 会随着 ht 的进一步增加而减小,这表明在塑性区域存在压痕深度依赖性。Er 的变化趋势也类似。基于我们的发现,首先,我们利用经典的赫兹接触力学建立了压痕硬度与接触半径与压痕深度比值之间的关系。然后,我们基于原子尺度的协同剪切机制开发了一个模型来解释大块金属玻璃中的压痕尺寸效应。此外,我们还观察到 H 与压痕弹性深度 he 与总深度 ht 的比值的立方相关,或者与压痕弹性功与总功的比值相关。我们的研究结果揭示了一种标度律,它揭示了硬度与塑性变形起始时的平均压力、流动硬度以及该比值之间的内在关系。这项工作强调了压痕深度效应源于弹性与塑性的相互作用,而非仅仅受压痕深度、接触面积或压头半径等因素的影响。这突显了其在理解及评估大块金属玻璃在亚微米尺度下的塑性变形中的关键作用。


Journal of the Mechanics and Physics of Solids

The impacts of thermoelastic anisotropy and grain boundary misorientation on microcracking in ceramics

Andrew R. Ericks, Frank W. Zok, Daniel S. Gianola, Matthew R. Begley

doi:10.1016/j.jmps.2024.106024

热弹性各向异性和晶界取向偏差对陶瓷微裂纹的影响

This paper examines the role of thermoelastic anisotropy on grain boundary cracking in brittle materials using a highly efficient computational framework. Energy release rates (ERRs) are computed for 35 materials spanning all seven crystal systems. Two crack geometries are considered: short interface cracks in isolated bicrystals plates, and cracked grain boundaries in polycrystal plates comprising periodic hexagonal grains. Crack driving forces are computed for penetration through the plate thickness (for cracks of width equal to the length of a hexagonal grain boundary), extensions along bicrystal interfaces, transgranular cracks that emerge from triple junctions, and kinking into bulk materials and at grain triple junctions. The high throughput computational framework produces probably distributions for ERRs arising from randomly oriented grains; the distributions for cracks at grain edges in polycrystals are broader than those for short cracks along bicrystal interfaces. A broad study of different grain configurations also illustrates that only the first 5-6 rings of neighboring grains influence crack driving forces for a given interface. The implications for interpreting microcracking observations, quantifying the performance of textured ceramics, and designing two-phase ceramic composites are briefly discussed.

本文用一个高效的计算框架研究了热弹性各向异性在脆性材料晶界开裂中的作用。计算了7种晶体体系中35种材料的能量释放率(ERRs)。考虑了两种裂纹几何形状:孤立双晶板中的短界面裂纹和由周期性六角形晶粒组成的多晶板中的晶界裂纹。裂纹驱动力的计算包括:穿透板厚(宽度等于六角形晶界长度的裂纹)、沿双晶界面延伸、从三结处出现的穿晶裂纹、以及在晶粒三结处扭成块状材料。高通量计算框架产生随机取向颗粒产生的ERRs的概率分布;多晶边缘裂纹的分布比双晶界面短裂纹的分布更宽。对不同晶粒结构的广泛研究也表明,只有相邻晶粒的前5-6环影响给定界面的裂纹驱动力。简要讨论了微裂纹观测解释、织构陶瓷性能量化和两相陶瓷复合材料设计的意义。


Hydromechanical field theory of plant morphogenesis

Hadrien Oliveri, Ibrahim Cheddadi

doi:10.1016/j.jmps.2025.106035

植物形态发生的流体力学场理论

The growth of plants is a hydromechanical phenomenon in which cells enlarge by absorbing water, while their walls expand and remodel under turgor-induced tension. In multicellular tissues, where cells are mechanically interconnected, morphogenesis results from the combined effect of local cell growths, which reflects the action of heterogeneous mechanical, physical, and chemical fields, each exerting varying degrees of nonlocal influence within the tissue. To describe this process, we propose a physical field theory of plant growth. This theory treats the tissue as a poromorphoelastic body, namely a growing poroelastic medium, where growth arises from pressure-induced deformations and osmotically-driven imbibition of the tissue. From this perspective, growing regions correspond to hydraulic sinks, leading to the possibility of complex non-local regulations, such as water competition and growth-induced water potential gradients. More in general, this work aims to establish foundations for a mechanistic, mechanical field theory of morphogenesis in plants, where growth arises from the interplay of multiple physical fields, and where biochemical regulations are integrated through specific physical parameters.

植物的生长是一种流体力学现象,细胞通过吸收水分而扩大,而细胞壁在膨胀引起的张力作用下膨胀和重塑。在多细胞组织中,细胞在机械上相互联系,形态发生是局部细胞生长的综合作用的结果,这反映了异质的机械、物理和化学场的作用,每个场在组织内施加不同程度的非局部影响。为了描述这一过程,我们提出了植物生长的物理场理论。该理论将组织视为孔隙形态弹性体,即生长的孔隙弹性介质,其生长源于压力诱导的变形和组织的渗透驱动的吸吮。从这个角度来看,生长区对应于水力汇,从而导致复杂的非局部调节的可能性,例如水竞争和生长诱导的水势梯度。更一般地说,这项工作旨在为植物形态发生的机械,机械场理论奠定基础,其中生长源于多个物理场的相互作用,并且生化调节通过特定的物理参数集成。


Thin-Walled Structures

Multi-patch isogeometric analysis for smart plates with distributed piezoelectric patches

Tao Liu, Xiangrong Sun, Jinde Zheng, Lu Wang, Qingyun Liu, Tinh Quoc Bui

doi:10.1016/j.tws.2025.112937

分布式压电贴片智能板的多贴片等几何分析

The previous isogeometric analysis (IGA) on piezoelectric smart structures mainly focused on plates and shells that were fully covered with piezoelectric materials. However, the piezoelectric materials in smart structures commonly exist in the form of patches that are locally attached to the substrate structures, in practical engineering applications. Thus, this paper aims to apply IGA to analyze the electro-mechanical coupled behaviors of distributed piezoelectric smart plates. The Nitsche-based non-conforming multi-patch technology is adopted to deal with the precision limitations associated with single-patch IGA for distributed piezoelectric smart plates. In accordance with first-order shear deformation theory (FSDT) and NURBS-based IGA, the non-conforming multi-patch governing equations for piezoelectric smart plates are then derived. In particular, the Nitsche’s method is adopted for addressing the non-conforming meshes and ensuring the continuity of the field variables on the coupling boundary between two adjacent patches. The developed methodology is further extended to analyze the fully-covered and distributed piezoelectric smart plates. Meanwhile, to enhance the general applicability of the method, the piezoelectric smart plates integrated with traditional piezoelectric ceramics and macro-fiber composite (MFC) materials are designed in numerical examples. Finally, comprehensive assessments for natural frequency and static response of piezoelectric smart plates are carried out and then compared with the existing reference solutions or the results calculated by ABAQUS software to demonstrate the effectiveness and accuracy of the developed method. These numerical examples validate that the proposed method is capable of addressing the limited accuracy of single-patch IGA in distributed piezoelectric smart structures.

以往对压电智能结构的等几何分析主要集中在被压电材料完全覆盖的板壳上。然而,在实际工程应用中,智能结构中的压电材料通常以贴片的形式存在,这些贴片局部附着在衬底结构上。因此,本文旨在应用IGA分析分布式压电智能板的机电耦合行为。采用基于nitsche的非一致性多贴片技术,解决了分布式压电智能板单贴片IGA的精度限制。根据一阶剪切变形理论(FSDT)和基于nurbs的IGA,推导了智能压电板的非协调多片控制方程。特别是采用Nitsche方法来处理不一致的网格,并保证相邻两个补丁之间耦合边界上场变量的连续性。将所开发的方法进一步扩展到分析全覆盖和分布式压电智能板。同时,为了提高方法的通用性,对传统压电陶瓷与宏纤维复合材料(MFC)相结合的压电智能板进行了数值算例设计。最后,对压电智能板的固有频率和静响应进行了综合评估,并与已有参考解或ABAQUS软件计算结果进行了比较,验证了所提方法的有效性和准确性。数值算例验证了该方法能够解决分布式压电智能结构中单片IGA精度有限的问题。


A machine learning-driven prediction of lower-bound buckling design load for cylindrical shells under localized axial compression

Xinyi Lin, Peng Jiao, Huangyang Xu, Xinshuang Li, Zhiping Chen

doi:10.1016/j.tws.2025.112960

局部轴压作用下圆柱壳下屈曲设计载荷的机器学习预测

Thin-walled cylindrical shells are extensively used across various fields because of their exceptional load-carrying efficiency. In practical applications, these structures are typically subjected to localized axial compression rather than the uniform axial compression considered in traditional research. A reliable and efficient buckling design method for cylindrical shells under such localized loads has not been developed to date. To address this challenge, a machine learning (ML) approach is proposed in this study for predicting the lower-bound buckling design load of cylindrical shells under localized axial compression. The artificial neural network (ANN) is selected as the ML model. Based on the modified energy barrier approach (MEBA), 500 samples are obtained by numerical simulations and their results are used to train the ANN model. The ANN model takes six geometric parameters, three material parameters, and one localized axial compression parameter as the inputs, while the lower-bound buckling load and the knockdown factor are the outputs. The feasibility and accuracy of the proposed ANN model are demonstrated by comparison with existing design codes and experimental results. The results suggest that this ML-based approach can fully exploit the load-carrying capacity of shells under localized axial compression, enabling more efficient and lightweight designs.

薄壁圆柱壳因其优异的承载效率而广泛应用于各个领域。在实际应用中,这些结构通常遭受局部轴压,而不是传统研究中认为的均匀轴压。目前还没有一种可靠而有效的圆柱壳在这种局部载荷作用下的屈曲设计方法。为了解决这一挑战,本研究提出了一种机器学习(ML)方法来预测局部轴向压缩下圆柱壳的下界屈曲设计载荷。选择人工神经网络(ANN)作为机器学习模型。基于修正能量势垒法(MEBA),对500个样本进行了数值模拟,并将模拟结果用于神经网络模型的训练。该模型以6个几何参数、3个材料参数和1个局部轴压参数为输入,以下界屈曲载荷和击倒因子为输出。通过与现有设计规范和实验结果的比较,验证了该模型的可行性和准确性。结果表明,这种基于ml的方法可以充分利用壳体在局部轴压下的承载能力,实现更高效、更轻量化的设计。


AM-FEMU: An optimization method for additive manufacturing simulation parameters based on finite element model updating, utilizing three-dimensional deformation and melt pool temperature fields

Ru Chen, Hanwen Xue, Qixian Zhong, Chenghao Zhang, Shiqing Li, Chuanqing Geng, Jiaye Zhao, Zhanwei Liu, Huimin Xie, Zhanfei Zhang

doi:10.1016/j.tws.2025.112962

AM-FEMU:一种基于有限元模型更新、利用三维变形和熔池温度场的增材制造仿真参数优化方法

Accurate model parameters are crucial for reliable metal additive manufacturing (AM) simulations, which are essential for understanding AM material formation mechanisms, designing AM components, and controlling manufacturing processes. This study addresses the discrepancy between AM simulations and experimental results by developing an Additive Manufacturing Finite Element Model Updating (AM-FEMU) method. The AM-FEMU method updates and optimizes the simulation parameters based on the temperature field of the melt pool and the deformation field of the substrate during the AM process. Online measurements of three-dimensional displacement and melt pool temperature were conducted using three-dimensional sampling moiré and multi-spectral colorimetric temperature measurement technologies. By comparing these measurements with finite element (FE) simulation, the heat source parameters and thermal expansion coefficient were updated successfully. Verification tests confirmed that the updated parameters significantly improved the accuracy of residual stress in AM simulations compared to the original parameters. This method promotes the application of FEMU in metal AM simulations, further providing a deeper understanding of the physical mechanism in metal AM process.

准确的模型参数对于可靠的金属增材制造(AM)模拟至关重要,这对于理解增材制造材料形成机制、设计增材制造部件和控制制造过程至关重要。本研究通过开发一种增材制造有限元模型更新(AM- femu)方法来解决增材制造仿真与实验结果之间的差异。AM- femu方法基于增材过程中熔池温度场和基材变形场对模拟参数进行更新和优化。采用三维采样仪和多光谱比色测温技术,实现了三维位移和熔池温度的在线测量。通过与有限元模拟结果的比较,成功地更新了热源参数和热膨胀系数。验证试验证实,与原始参数相比,更新后的参数显著提高了增材制造模拟中残余应力的准确性。该方法促进了FEMU在金属增材制造模拟中的应用,进一步加深了对金属增材制造过程物理机制的理解。


Impact angle-dependent residual burst strength of thin-walled composite pressure vessels under low-velocity impact

Honghao Liu, Lei Zu, Qian Zhang, Guiming Zhang, Jianhui Fu, Helin Pan, Qiaoguo Wu, Xiaolong Jia, Lichuan Zhou

doi:10.1016/j.tws.2025.112963

低速冲击下薄壁复合材料压力容器残余破裂强度与冲击角的关系

Thin-walled composite pressure vessels exhibit a promising potential for energy storage, but they are vulnerable to barely visible damage from random impacts. Yet, angle-dependent damage mechanisms remain unclear, challenging the structural design to resist impact loadings. Herein, this study elucidates the residual burst strength of composite vessels under low-velocity impacts, guiding impact-resistant design at varying impact angles. The impact damage model based on a segmented golden-section search algorithm enhances computational efficiency and accuracy. Results show that matrix damage intensifies within helical layers under small-angle oblique impacts, while fiber damage consistently concentrates in hoop layers, with delamination between the hoop and helical layers decreasing from the outer layers inward. Furthermore, impacts at different angles shift potential failure locations within the vessel, with small-angle oblique impacts resulting in a low peak impact force. Notably, increasing the proportion of the helical layer enhances resistance to oblique impacts, while thicker hoop layers improve resistance to vertical impacts; at high energies, both layers should be thickened regardless of impact angle. This work not only offers new insights into angle-dependent impact damage but also contributes to the design for impact-resistant enhancement of advanced composite pressure vessels.

薄壁复合材料压力容器在能量存储方面表现出很好的潜力,但它们很容易受到随机撞击造成的几乎看不见的损伤。然而,角度相关的损伤机制仍不清楚,这对结构设计抵抗冲击载荷提出了挑战。本文研究了复合材料容器在低速冲击下的残余爆裂强度,为不同冲击角度下的抗冲击设计提供指导。基于分段黄金分割搜索算法的冲击损伤模型提高了计算效率和精度。结果表明:在小角度斜冲击下,螺旋层内基体损伤加剧,而纤维损伤始终集中在环形层内,环形层与螺旋层之间的分层从外层向内逐渐减少;此外,不同角度的撞击会改变容器内潜在的失效位置,小角度的倾斜撞击会导致较低的峰值冲击力。值得注意的是,增加螺旋层的比例可以增强斜向冲击的阻力,而更厚的箍层可以提高垂直冲击的阻力;在高能量下,无论撞击角度如何,两层都应加厚。这项工作不仅为角度相关的冲击损伤提供了新的见解,而且有助于提高先进复合材料压力容器的抗冲击设计。



来源:复合材料力学仿真Composites FEM
ACTMechanicalAdditiveSystemAbaqus复合材料化学通用增材ECAD裂纹参数优化理论材料控制试验
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【新文速递】2025年1月8日固体力学SCI期刊最新文章

今日更新:International Journal of Solids and Structures 1 篇,Journal of the Mechanics and Physics of Solids 1 篇,International Journal of Plasticity 1 篇,Thin-Walled Structures 6 篇International Journal of Solids and StructuresDeployment dynamics of a high strain deployable rolled-up composite SAR antennaAnnalisa Tresoldi, Jason Shore, Alfonso Pagani, Guglielmo Agliettidoi:10.1016/j.ijsolstr.2024.113208一种高应变可展开卷式复合SAR天线的展开动力学The Deployable Rolled-up Composite Antenna - Synthetic Aperture Radar (DERCA-SAR) concept design is proposed for a 12U CubeSat low-power remote sensing application. A SAR reflectarray system is considered to be implemented on a High-Strain Composite (HSC) structure with a shallow “tape-measure” inspired shape. The stiffness required in the deployed state is provided by the cross-sectional curvature of the shell, which will be rigidly maintained at the root during stowage. To provide a low-mass solution for this application, the DERCA-SAR technology considers flattening and coiling the shell tip until it reaches the clamped root and deploys by releasing the elastic strain energy stored in the coiled configuration. In this paper, two analytical models are developed to describe the deployment dynamics of this structure and predict the deployment velocity that may impact the antenna performance. Given an initial coil radius r, which is much smaller than the natural radius R to fit a nanosatellite platform, the deployment occurs in two stages that have been revealed through experiments. The first blossoming phase is described as an expanding and uncoiling process based on the Lagrangian approach. The second and more chaotic phase of the deployment is modelled using a Hencky-type model that discretises the shell’s structure in a multi-pendulum system connected by elastic rotational hinges/springs. In this model, the shell’s stiffness is made to locally change based on the characteristic tape springs’ moment–rotation relationship and the implementation of a stiffness function. The analytical results are then compared to experimental data derived from deployment testing on samples of the shells with different material properties. The predictions from the two models capture the significant trends of the data well, and predict the maximum speed with an error of <10%.可展开卷曲复合材料天线 - 合成孔径雷达(DERCA-SAR)概念设计是为 12U 立方体卫星低功耗遥感应用而提出的。考虑在一种具有浅“卷尺”启发式形状的高应变复合材料(HSC)结构上实现 SAR 反射阵列系统。展开状态所需的刚度由壳体的横截面曲率提供,在收拢时将在根部牢固保持。为了为该应用提供低质量的解决方案,DERCA-SAR 技术考虑将壳体尖端压平并卷曲,直至其到达夹紧的根部,然后通过释放卷曲配置中储存的弹性应变能来展开。在本文中,开发了两个分析模型来描述该结构的展开动力学,并预测可能影响天线性能的展开速度。给定初始卷曲半径 r,其远小于自然半径 R 以适应纳米卫星平台,通过实验揭示了展开过程分为两个阶段。第一个开花阶段被描述为基于拉格朗日方法的扩展和展开过程。第二阶段也是更混乱的展开阶段采用了一种亨克型模型进行建模,该模型将壳体结构离散化为通过弹性旋转铰链/弹簧连接的多摆系统。在此模型中,壳体的刚度根据特征带弹簧的力矩 - 旋转关系以及刚度函数的实施而局部变化。然后将分析结果与从具有不同材料特性的壳体样本的展开测试中得出的实验数据进行比较。这两个模型的预测很好地捕捉了数据的主要趋势,并且对最大速度的预测误差小于 10%。Journal of the Mechanics and Physics of SolidsA Nonlinear Thermo-Visco-Green-Elastic Constitutive Model for Mullins Damage of Shape Memory Polymers under Giant ElongationsAlireza Ostadrahimi, Alireza Enferadi, Mostafa Baghani, Siavash Sarrafan, Guoqiang Lidoi:10.1016/j.jmps.2025.106029巨伸长下形状记忆聚合物Mullins损伤的非线性热粘绿弹本构模型In this paper, we introduce a comprehensive 3D finite-deformation constitutive model for shape memory polymers focused on addressing the Mullins effect when subjected to substantial elongation, reaching up to 200% strain. Considering only four Maxwell branches with nonlinear viscous components integrated with the WLF equation, our modeling framework inherently ensures thermodynamic consistency without imposing excessive constraints, linear (Boltzmann) or phenomenological modeling. This approach allows the study of time- and temperature-dependent behaviors, including stress relaxation, cyclic loadings related to the shape memory effect, shape and force recovery, and damage phenomena in SMPs under large elongations. The model integrates hyperelasticity and stress-softening effects while employing the concept of rational thermodynamics and internal state variables in the realm of the thermo-visco-green-elastic continuum approach. Additionally, we delve into the influence of strain levels on stretch-induced softening effects and their subsequent impact on free-shape recovery behavior. To streamline characterization and calibration, we conducted extensive experimental uniaxial cyclic tests across various strain rates and temperatures on a shape memory polymer. The model is compatible with both COMSOL and Abaqus software, enabling robust simulations of complex material responses. Through rigorous comparison against experimental data and extensive finite element multi-physics analysis simulations, we evaluate the model's performance via several multi-physics case studies and validate our proposed algorithm while minimizing both the number of parameters and computational costs.在本文中,我们为形状记忆聚合物引入了一个全面的三维有限变形本构模型,重点解决了在达到200%应变的大幅伸长时的穆林斯效应。考虑到只有四个麦克斯韦分支与非线性粘性分量与WLF方程集成,我们的建模框架内在地确保热力学一致性,而不施加过多的约束,线性(玻尔兹曼)或现象学建模。这种方法可以研究时间和温度相关的行为,包括应力松弛、与形状记忆效应相关的循环载荷、形状和力恢复,以及大伸长下smp的损伤现象。该模型综合了超弹性和应力软化效应,同时采用了热粘绿弹性连续介质领域的理性热力学概念和内部状态变量。此外,我们还深入研究了应变水平对拉伸引起的软化效应的影响及其对自由形状恢复行为的后续影响。为了简化表征和校准,我们在形状记忆聚合物上进行了各种应变速率和温度下的大量单轴循环实验。该模型与COMSOL和Abaqus软件兼容,能够对复杂的材料响应进行稳健的模拟。通过与实验数据和广泛的有限元多物理场分析模拟的严格比较,我们通过几个多物理场案例研究评估了模型的性能,并验证了我们提出的算法,同时最小化了参数数量和计算成本。International Journal of PlasticityEnhancing the strain-hardening rate and uniform tensile ductility of lightweight refractory high-entropy alloys by tailoring multi-scale heterostructure strategyYansong Zhang, Huaming Wang, Junwei Yang, Yanyan Zhu, Jia Li, Zhuo Li, Bing Su, Bingsen Liu, Chunjie Shendoi:10.1016/j.ijplas.2024.104237 采用定制多尺度异质结构策略提高轻质难熔高熵合金的应变硬化率和均匀拉伸延展性During the deformation of body-centered cubic (BCC) structured lightweight refractory high-entropy alloys (LRHEAs), strain localization caused by a low strain-hardening rate (SHR) induces premature alloy necking, resulting in poor uniform tensile ductility (UTD) and restricts their processability and applicability. In this study, we improved the SHR of the alloys from negative to 1.5 GPa by tailoring multi-scale heterostructures, including the microscopic bimodal grain distribution, submicron spherical C14 Laves phase, nanoscale local chemical fluctuations (LCFs), and atomic clusters less than 1nm. The strength of the alloy was raised by 13.8%, and the UTD increased by 710% compared with the initial homogenized sample, and overall performance was superior to most LRHEAs. Bimodal grain interfaces can effectively coordinate the strain distribution between the two during deformation, accelerating the generation and storage of geometrically necessary dislocations (GNDs), and the back stress accumulates and increases with strain, stabilizing the hardening ability. Meanwhile, the meticulously dispersed C14 Laves phase plays a role in precipitation strengthening without compromising plasticity. The matrix's LCFs and Al-Zr atomic clusters can further regulate the morphology and distribution of statistically stored dislocations (SSDs). On the one hand, they could effectively pin dislocations and cause them to bend, increasing the migration resistance of SSDs; on the other hand, dislocation tangles resulting from microbands blocking and the interaction of multi-slip systems activate new dislocation sources, which lead to the rapid expansion of secondary microbands in a reticular manner. Those significantly increase the synchronous dislocation multiplication rate and dynamic dislocation density during plastic deformation, maintaining high and sustained SHR of alloys. Therefore, the SHR of LRHEA can be effectively improved by introducing multi-scale heterogeneous structures to optimize the coordination of GND and SSD density and distribution, thus achieving an excellent match between strength and UTD.在体心立方(BCC)结构轻质耐火高熵合金(LRHEAs)变形过程中,由于低应变硬化率(SHR)导致的应变局部化导致合金过早颈缩,导致均匀拉伸延展性(UTD)较差,限制了其加工性能和适用性。在这项研究中,我们通过调整多尺度异质结构,包括微观双峰晶粒分布、亚微米球形C14 Laves相、纳米尺度局部化学波动(LCFs)和小于1nm的原子团簇,将合金的SHR从负提高到1.5 GPa。与初始均质样品相比,合金强度提高了13.8%,UTD提高了710%,整体性能优于大多数LRHEAs。双峰型晶粒界面能有效协调变形过程中两者之间的应变分布,加速几何必要位错(GNDs)的产生和储存,背应力随应变积累和增大,稳定了硬化能力。同时,精心分散的C14 Laves相在不影响塑性的前提下起到了沉淀强化的作用。矩阵的LCFs和Al-Zr原子团簇可以进一步调节统计存储位错(ssd)的形态和分布。一方面,它们可以有效地钉住位错并使其弯曲,增加ssd的迁移阻力;另一方面,微带阻塞和多滑移系统相互作用导致的位错缠结激活了新的位错源,导致次级微带以网状方式快速扩展。显著提高了塑性变形过程中的同步位错倍增率和动态位错密度,保持了合金的高持久SHR。因此,通过引入多尺度异质结构,优化GND和SSD密度和分布的协调性,可以有效提高LRHEA的SHR,从而实现强度和UTD的良好匹配。Thin-Walled StructuresUltra-thin flattened piezoelectric drivers for aerospace filter wheelYanhu Zhang, Zhihao Chen, Yi Zheng, Jiali Fan, Yanfei Ma, Yuhua Zhou, Zijian Zhang, Ji Zhou, Zhengbao Yangdoi:10.1016/j.tws.2025.112913航空滤光轮用超薄扁平压电驱动器With the advantages of thin structure, high efficiency, and high resolution, the in-plane thin-plate ultrasonic motors have been commercially produced and used in advanced applications, especially low-voltage driving for smart devices and precision positioning in aerospace services. The filter wheel mechanism is complex because of the stacked and heavy transmission system and additional electronic control modules, which hinder online detection efficiency and the development of miniaturized detection technology in aerospace. An in-plane linear ultrasonic motor prototype was developed using a longitudinal-bending hybrid vibration of the thin plate with the arranged grooves for flexibilization. The elliptical moving locus of the double driving feet was analyzed, and the working principle of this motor was presented. A flexible stator was optimized using the finite element method, considering the frequency degeneracy of longitudinal and bending vibrations. Meanwhile, the output performance of the piezoelectric motor was experimentally investigated. Results show that the proposed motor can work in a wide range of working conditions from 75Vpp to 350Vpp. The forward (to the right) and backward (to the left) speeds under the no-load condition get to 0.25m/s and 0.22m/s, respectively; the maximum thrust is 3.4 N at the exciting voltage of 200Vpp@45.7kHz, and the thrust-to-weight ratio reaches 47 (the stator weight is 7.36 g). Under the low voltage driving of 75Vpp@45.7kHz, the proposed motor can get a thrust of 0.5 N and a no-load speed of 80 mm/s. Compared with the in-plane linear ultrasonic motor without grooves, the amplitude of the driving foot for the proposed motor with grooves increases. After the stabilization of the stator, the motor's no-load speed increases by 51.5%, and the maximum thrust force increases by 36%. This study is conducive to the miniaturization, lightweight design, and manufacturing thin-plate motors for aerospace services.平面内薄板超声电机具有结构薄、效率高、分辨率高等优点,已实现商业化生产,并在智能设备低压驱动和航空航天精密定位等领域得到了广泛应用。过滤轮机构结构复杂,传动系统堆叠沉重,附加电子控制模块,阻碍了在线检测效率和航空航天领域小型化检测技术的发展。利用薄板纵弯混合振动,设计了一种平面内直线超声电机样机。分析了双驱动脚的椭圆运动轨迹,介绍了该电机的工作原理。考虑了柔性定子纵向振动和弯曲振动的频率退化,采用有限元法对柔性定子进行了优化。同时,对压电电机的输出性能进行了实验研究。结果表明,所提出的电机可以在75Vpp到350Vpp的较宽工作条件下工作。空载状态下,前进(向右)速度达到0.25m/s,后退(向左)速度达到0.22m/s;在200Vpp@45.7kHz激励电压下,电机的最大推力为3.4 N,推重比达到47(定子重量为7.36 g),在75Vpp@45.7kHz低压驱动下,电机的推力为0.5 N,空载速度为80 mm/s。与不带沟槽的平面内直线超声电机相比,带沟槽电机的驱动脚振幅增大。定子稳定后,电机空载转速提高51.5%,最大推力提高36%。该研究有助于航空航天服务中薄板电机的小型化、轻量化设计和制造。Lateral Load Behavior of Prestressed Segmental Concrete Towers with Hollow Tapered GeometryYuhang Wang, Sheng Xu, Xuhong Zhou, Lixian Zhang, Xiaogang Huangdoi:10.1016/j.tws.2025.112914空心锥形预应力节段混凝土塔的侧向荷载行为Wind turbine concrete towers are typically constructed by stacking hollow segments and assembling them into a tapered structure, termed as prestressed segmental concrete towers (PSCTs). Displacing the PSCT continually will cause adjacent segments to rock at the horizontal joints. This study investigates the lateral load behavior of PSCTs with different joint openings. The effects of geometric and rebar parameters on the tower's global responses were analyzed through local joint responses, including joint curvatures, material stresses and strains. The results indicate that, with significant gap openings along the tower height, the lateral load can increase by up to 2.2 times the decompression load without a noticeable reduction in stiffness.风力涡轮机混凝土塔通常是通过堆叠空心段并将其组装成锥形结构来建造的,称为预应力节段混凝土塔(psct)。连续位移PSCT将导致相邻段在水平节理处发生岩石变形。本研究探讨了具有不同关节开口的psct的侧向荷载行为。通过节点的局部响应,包括节点曲率、材料应力和应变,分析了几何参数和钢筋参数对塔整体响应的影响。结果表明,当沿塔高方向有明显的间隙时,侧移荷载可以增加到减压荷载的2.2倍,而刚度却没有明显降低。Mechanical performance enhancement of bionic sandwich circular tubes under axial compressionJin kangrui, Liu zhifang, Zhang tianhui, Lei jianying, Li shiqiangdoi:10.1016/j.tws.2025.112920仿生夹层圆管轴向压缩力学性能增强研究Three novel bionic sandwich circular tube designs were developed, inspired by the macroscopic structure of the lotus petiole. Their mechanical performance under axial compression was comprehensively investigated using experimental, theoretical, and numerical methods. Experimental results revealed that the external tubes of all configurations exhibited a characteristic concertina-mode deformation during axial compression. A theoretical model was established to analyze the static mechanical behavior of these tubes. This model not only predicts the compression strength but also incorporates the strain-hardening behavior of the foam material and accounts for the interaction effects between the bionic core and the overall compressive performance of the tube. The predicted mean compression force was found to be in close agreement with the experimental results. Numerical simulations were also conducted to investigate the impact of internal tube thickness and core density gradient on the energy absorption capacity of the bionic sandwich circular tubes. The results indicated that the inclusion of an internal tube significantly enhanced the specific energy absorption (SEA), peak compression force (PCF), and mean compression force (MCF) of the structure. Specifically, the three bionic sandwich circular tubes with an internal tube wall thickness of 0.6 mm exhibited improvements in SEA of 20.14%, 27.42%, and 33.13%, respectively, compared to structures without an internal tube. Additionally, for bionic sandwich circular tubes with a density gradient, all performance evaluation indices are higher than those of the corresponding tubes with uniform density.受莲花叶柄宏观结构的启发,开发了三种新型仿生三明治圆管设计。采用实验、理论和数值方法对其轴向压缩力学性能进行了综合研究。实验结果表明,在轴向压缩过程中,所有构型的外管均表现出典型的手风琴型变形。建立了理论模型,分析了这些管的静态力学行为。该模型不仅预测了泡沫材料的抗压强度,而且考虑了泡沫材料的应变硬化行为,并考虑了仿生芯与管材整体抗压性能之间的相互作用。预测的平均压缩力与实验结果吻合较好。通过数值模拟研究了内管厚度和芯密度梯度对仿生夹层圆管吸能能力的影响。结果表明,内管的加入显著提高了结构的比能吸收(SEA)、峰值压缩力(PCF)和平均压缩力(MCF)。具体来说,与没有内管的结构相比,三根内管壁厚度为0.6 mm的仿生三明治圆形管的SEA分别提高了20.14%、27.42%和33.13%。具有密度梯度的仿生夹层圆管的各项性能评价指标均高于均匀密度的仿生夹层圆管。Progress in Vat Photopolymerisation Additive Manufacturing of Ceramic Lattice Structures and ApplicationsQumail Arshad, Muhammad Saqib, Muhammad Anas Arshad, Mohsin Raza, Muhammad Irfan Hussain, Ali Asghar, Xin Luo, Zhangwei Chendoi:10.1016/j.tws.2025.112918 陶瓷晶格结构的还原光聚合增材制造及其应用研究进展Additive manufacturing (AM) through vat photopolymerisation (VPP) of ceramics has emerged as a transformative approach, enabling precise geometric control which is advantageous for various industrial applications. Despite its potential, the fabrication process encounters significant challenges, including preparing high solid-content slurries, substantial shrinkage, and crack formation. This review summarises the recent advancements in VPP technology for the development of ceramic lattice structures (CLS), focusing on (1) the preparation of ceramic-based feedstocks, detailing the influence of particle size distribution, solid loading, and rheological behaviour on feedstock optimisation; (2) the de-binding and sintering processes, examining chemical and thermal methods along with shrinkage considerations; (3) the mechanical performance evaluation of fabricated lattice structures, including assessments of stiffness, strength, structural integrity, and topology comparisons; and (4) potential applications across industries. Furthermore, this review addresses the prevailing challenges in VPP, such as slurry design complexities, dimensional inaccuracies, surface imperfections, and thermal deformation issues. Recommendations for overcoming these challenges are proposed. This comprehensive review aims to provide valuable insights that facilitate the production of intricate, high-performance ceramic lattices through VPP, thereby enhancing their applicability across a diverse range of industries.通过陶瓷的还原光聚合(VPP)的增材制造(AM)已经成为一种变革性的方法,实现精确的几何控制,这对各种工业应用都是有利的。尽管具有潜力,但制造过程遇到了重大挑战,包括制备高固含量的浆料,大幅收缩和裂缝形成。本文综述了VPP技术在陶瓷晶格结构(CLS)开发中的最新进展,重点是:(1)陶瓷基原料的制备,详细介绍了粒度分布、固体负载和流变行为对原料优化的影响;(2)脱粘和烧结过程,检查化学和热方法以及收缩考虑;(3)装配式晶格结构的力学性能评估,包括刚度、强度、结构完整性评估和拓扑比较;(4)跨行业的潜在应用。此外,本文还讨论了VPP中存在的挑战,如浆液设计复杂性、尺寸不精确、表面缺陷和热变形问题。提出了克服这些挑战的建议。这篇全面的综述旨在通过VPP提供有价值的见解,以促进复杂的高性能陶瓷晶格的生产,从而提高其在各种行业的适用性。Compression-bending behavior of prestressed concrete filled steel tubular tower for onshore wind turbinesYu-Sen Liu, Yu-Hang Wang, Xu-Hong Zhou, Chao Hu, Wei Ren, Ji-Chun Liudoi:10.1016/j.tws.2025.112921陆上风力发电机组预应力钢管混凝土塔的压弯性能Prestressed concrete-filled steel tubular (CFST) lattice tower is a novel high-rise structure designed for onshore low-wind-speed areas, where compression-bending loads are the primary design consideration. To investigate the mechanical performance of prestressed CFST lattice tower, a quasi-static scaled model test was conducted under compression-bending loads. Test results revealed that the failure mode of the specimens predominantly exhibited flexural ductile failure, characterized by steel tearing and concrete crushing at the chord base. The prestress loss was found to be closely correlated with structural bending deformation. Utilizing the finite element (FE) model validated by experimental results, effects of design parameters, including axial compression ratio, material strength, specimen dimensions, and prestress, on the load-displacement responses of prestressed CFST lattice tower were systematically analyzed. Limit values for thickness ratios and diameter ratios of batten/chord, which enhanced material utilization efficiency in lattice towers, were then provided. Building upon the equivalent stiffness method, a computational analysis was conducted to standardize variable cross-sections into equivalent uniform cross-sections for CFST lattice towers. Integrating FE parametric analysis, current design codes, and limit equilibrium state methods, a novel approach for the calculation of compression-bending ultimate capacity of prestressed CFST lattice towers was proposed.预应力钢管混凝土(CFST)格塔是一种新型的高层结构,设计用于陆上低风速地区,在那里压缩弯曲荷载是主要的设计考虑因素。为研究预应力钢管混凝土格塔在压缩弯曲荷载作用下的力学性能,进行了准静态比例模型试验。试验结果表明,试件的破坏模式主要表现为弯延性破坏,主要表现为弦底钢筋撕裂和混凝土破碎。预应力损失与结构弯曲变形密切相关。利用经试验验证的有限元模型,系统分析了轴压比、材料强度、试件尺寸、预应力等设计参数对预应力钢管混凝土格构塔荷载-位移响应的影响。给出了提高格子塔材料利用率的板条/弦材厚度比和直径比的极限值。在等效刚度法的基础上,对钢管混凝土格构塔的变截面标准化为等效均匀截面进行了计算分析。结合有限元参数分析、现行设计规范和极限平衡状态法,提出了一种预应力钢管混凝土格构塔压弯极限承载力计算的新方法。Mechanical properties and deformation behavior of porous titanium alloy structures with different femoral inclination angleBibo Yao, Hai Li, Zhenhua Li, Meihong Liu, Yuyang Peng, Huili Fandoi:10.1016/j.tws.2025.112922 不同股骨倾角下多孔钛合金组织的力学性能及变形行为In the anatomical structure of the natural femur, there is typically a characteristic inclination angle relative to the vertical direction. However, the influence of this inclination angle on mechanical performance remains unclear. Therefore, in this study, the N-type porous structure with 7° inclination angle and the U-type porous structure without inclination angle were designed by topology optimization technology. They were fabricated by selective laser melting (SLM) technology, and their mechanical properties, deformation behavior and energy absorption were studied by quasi-static compression test and simulation. The stress-strain curve of porous structure has elastic stage, plateau stage and densification stage. The elastic modulus and yield strength of the N-type porous structure are 25.39-35.7 GPa and 127.76-295.60 MPa, respectively. The elastic modulus and yield strength of the U-type porous structure are 25.15-49.44 GPa and 128.86-434.21 MPa, respectively. The Young's modulus and yield strength are found to be within the range of bones in the N-type porous structure when the pore sizes are 0.7, 0.8, and 0.9 mm. However, only the pore sizes with 0.8 and 0.9 mm in the U-type porous structure meet the demands of human bones. The deformation behavior of N-type porous structure is dominated by 45° shear fracture. The U-type porous structure shears after stacking layer by layer. The stress concentration of the N-type porous structure is evenly distributed in the strut, while the stress concentration of the U-type porous structure is dispersed on both sides. In addition, the displacement distribution of the U-type porous structure has shifted to the left, while the displacement distribution of the N-type porous structure is more uniform. When the pore size are 0.6 and 0.7 mm, the energy absorption efficiency of the N-type porous structure is lower than that of the U-type porous structure, while when the pore size are 0.8 and 0.9 mm, the results are opposite. Therefore, the N-type porous structure can reduce the stress shielding effect and has a more uniform stress distribution, which better meets the implant requirements.在天然股骨的解剖结构中,相对于垂直方向有一个典型的特征倾斜角。然而,这种倾角对力学性能的影响尚不清楚。因此,本研究采用拓扑优化技术设计了7°倾角的n型多孔结构和无倾角的u型多孔结构。采用选择性激光熔化(SLM)技术制备了复合材料,通过准静态压缩试验和模拟研究了复合材料的力学性能、变形行为和能量吸收。多孔结构的应力-应变曲线分为弹性阶段、平台阶段和致密化阶段。n型多孔结构的弹性模量为25.39 ~ 35.7 GPa,屈服强度为127.76 ~ 295.60 MPa。u型多孔结构的弹性模量为25.15 ~ 49.44 GPa,屈服强度为128.86 ~ 434.21 MPa。当孔径为0.7、0.8和0.9 mm时,n型多孔结构的杨氏模量和屈服强度均在骨骼范围内。然而,u型多孔结构中只有0.8和0.9 mm的孔径才符合人体骨骼的要求。n型多孔结构的变形行为以45°剪切断裂为主。u型多孔结构层叠后剪切。n型多孔结构的应力集中均匀地分布在支板内,而u型多孔结构的应力集中分散在两侧。此外,u型多孔结构的位移分布有左移现象,而n型多孔结构的位移分布更为均匀。当孔径为0.6和0.7 mm时,n型多孔结构的吸能效率低于u型多孔结构,而当孔径为0.8和0.9 mm时,结果相反。因此,n型多孔结构可以减少应力屏蔽效应,应力分布更加均匀,更好地满足种植体的要求。来源:复合材料力学仿真Composites FEM

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