今日更新:International Journal of Solids and Structures 1 篇,International Journal of Plasticity 2 篇,Thin-Walled Structures 4 篇
Fatigue crack growth analysis based on energy parameters: A literature review
F.V. Antunes, E.R. Sérgio, P.M. Cerezo, P. Lopez-Crespo, D.M. Neto
doi:10.1016/j.ijsolstr.2025.113355
基于能量参数的疲劳裂纹扩展分析:文献综述
Fatigue crack growth (FCG) in metallic materials has been studied using non-linear parameters, which permit a better understanding of crack tip damage. The objective here is to make a literature review about the use of energy parameters in this context. Fundamental concepts are presented, namely the different types of energy that can be identified (the external work, the macroscopic elastic energy, the plastic dissipation, the internal potential energy and the thermal energy). FCG rate has been related with the dissipated energy measured externally, with the dissipated energy in the reversed plastic zone, with a punctual value of dissipated density energy at a critical location ahead of crack tip and with the thermal energy. The links between FCG mechanisms and energy parameters are exploited and guidelines for their use are proposed.
利用非线性参数对金属材料的疲劳裂纹扩展进行了研究,从而更好地理解裂纹尖端的损伤。本文的目的是对在这种情况下使用能量参数进行文献综述。提出了基本概念,即可以识别的不同类型的能量(外部功、宏观弹性能、塑性耗散、内部势能和热能)。FCG速率与外部测量的耗散能有关,与反向塑性区的耗散能有关,与裂纹尖端前关键位置的耗散密度能准时值有关,与热能有关。利用了FCG机制和能量参数之间的联系,并提出了使用指南。
Phase-specific tailoring strategy for synergetic and prolonged work hardening to achieve superior strength-plasticity in lamellar-structured alloy
Yumeng Zhang, Ran Chen, Yixuan Hu, Chenyang Wang, Yao Shen, Xiaodong Wang
doi:10.1016/j.ijplas.2025.104317
层状组织合金协同长时间加工硬化的相位定制策略,以获得优异的强度塑性
The pursuit of alloys that integrate high strength and substantial plasticity persists across various industries. Nevertheless, alloys engineered for elevated strength commonly manifest unsustainable work hardening, ultimately leading to a decline in plasticity. Dual- or even multi-phase systems offer vast potential for novel microstructural engineering aimed at harmonizing these inversely related property requirements. Here, heterogeneous lamellar structure consisting of alternating austenite and ferrite lamellae is explored to decouple and leverage the distinct roles of individual phases in a dual-phase system. This phase-specific tailoring strategy meticulously manipulates intra-phase microstructure, and tunes the lamella thickness to promote both high initial strength and prolonged work hardening. The significantly enhanced strength benefits from pre-existing defects, interfaces strengthening and quasi iso-strain deformation mode while high plasticity originates from relatively uniform strain partitioning between phases across a wide strain range achieved through exploiting various hardening components. For austenite, prolonged work hardening is achieved by sequential utilization of dislocation hardening followed by martensitic transformation hardening. Moreover, the martensite laths in favorable configuration along with the retained austenite contribute to retarding cracking. For ferrite, wide-range work hardening is ensured by expanding the potential for dislocation activities which lowers initial density and raises peak density through reducing the space in the thickness dimension. Such innovation elevates the traditionally inferior work-hardening capability of high-strength BCC structure to an exceptional level. The resultant alloy, while boosting nearly twice the yield strength of its conventional counterpart, exhibits a total elongation of 45%. This strategy holds potential for broad application across dual- and multi-phase systems and proposes a new avenue for enhancing plasticity in high-strength lamellar-structured alloys.
对高强度和高塑性合金的追求贯穿于各个行业。然而,为提高强度而设计的合金通常表现为不可持续的加工硬化,最终导致塑性下降。双相甚至多相系统为旨在协调这些反向相关的性能要求的新型微结构工程提供了巨大的潜力。本文探讨了由奥氏体和铁素体交替片层组成的非均相片层结构,以解耦并利用双相系统中各个相的不同作用。这种针对相的定制策略精心控制相内微观结构,并调整薄片厚度,以提高初始强度和延长加工硬化时间。强度的显著提高得益于预先存在的缺陷、界面强化和准等应变变形模式,而高塑性源于利用各种硬化成分在宽应变范围内实现相间相对均匀的应变分配。对于奥氏体,通过顺序利用位错硬化和马氏体相变硬化来实现长时间的加工硬化。此外,良好形态的马氏体板条和残留的奥氏体有助于延缓开裂。对于铁素体来说,通过扩大位错活动的潜力来保证大范围的加工硬化,从而降低初始密度,并通过减小厚度尺寸中的空间来提高峰值密度。这种创新将传统上较差的高强度BCC结构的加工硬化能力提升到一个特殊的水平。所得合金的屈服强度几乎是常规合金的两倍,总伸长率达到45%。该策略具有广泛应用于双相和多相体系的潜力,并为提高高强度层状结构合金的塑性提供了新的途径。
Statistical evaluation of microscale stress conditions leading to void nucleation in the weak shock regime
Noah J. Schmelzer, Evan J. Lieberman, Nan Chen, Samuel D. Dunham, Veronica Anghel, George T. Gray, Curt A. Bronkhorst
doi:10.1016/j.ijplas.2025.104318
弱冲击条件下导致空穴成核的微尺度应力条件的统计评价
We investigate the heterogeneity of the stress state driven by anisotropic deformation response at the single crystal level through five statistical volume element (SVE) calculations of polycrystalline BCC tantalum. This work focuses on grain boundaries as a prominent material defect type prone to void nucleation based upon experimental observations of predominantly intergranular void nucleation in this material. The SVEs are constructed to be statistically representative of larger volumes of material and are meshed such that mean and standard deviation of grain size and orientation information is reconstructed. The computational meshes feature hexahedral (brick) elements and smooth conformal grain boundaries where significant stress concentration is known to occur, a tail effect of interest in the extreme events process of dynamic ductile damage. An existing micromechanical crystallographic plasticity model shown to capture the single crystal behavior of BCC tantalum well is used to perform the polycrystal calculations. The model includes representation of the non-Schmid effect of non-planar screw dislocation kinetics in tantalum. A three-dimensional stress state time profile predicted by damage modeling of a flyer plate impact experiment is applied as boundary conditions to each SVE. Resulting grain boundary stress state statistics are strongly non-Gaussian. Significant structural evolution is observed within the compressive hold before unloading into tension in the stress profile. Strong angular dependence of grain boundary traction magnitude with shock direction is observed. Non-Schmid effects continue to suggest their influence on propensity of microstructural defect types to nucleate voids. A general void nucleation criterion is proposed using probability theory. The general framework is specified to polycrystalline BCC tantalum in the weak shock regime to include the SVE calculations and literature molecular dynamics calculations of grain boundary void nucleation strength. Probability density functions (PDFs) are used to describe the interaction between the local stress state heterogeneity and the distributed grain boundary void nucleation strength state. A causation entropy maximization procedure removes the requirement for ad hoc selection of a PDF functional form and provides a rigorous procedure for data-based PDF determination. The resulting physically informed PDF describes the spatial appearance frequency of nucleated voids as a function of applied macroscale pressure. Lower length scale physics are thus packaged in a precise and computationally efficient way to provide computational plasticity insight to macroscale dynamic ductile damage models.
通过对多晶BCC钽的五种统计体积元(SVE)计算,研究了单晶水平上各向异性变形响应驱动的应力状态的非均质性。本研究的重点是晶界作为一种突出的材料缺陷类型,基于实验观察,晶界在这种材料中主要是晶间空洞成核。sve被构造成在统计上代表更大体积的材料,并被网格化,以便重建粒度和取向信息的平均值和标准差。计算网格具有六面体(砖)单元和光滑的共形晶界,其中已知会发生显著的应力集中,这是动态延性损伤极端事件过程中感兴趣的尾效应。现有的微力学晶体塑性模型可以很好地捕捉BCC钽的单晶行为,并用于进行多晶计算。该模型包含了钽中非平面螺位错动力学的非施密德效应。采用基于飞片冲击实验损伤模型预测的三维应力状态时间分布作为各SVE的边界条件。由此产生的晶界应力状态统计是非高斯态的。在应力剖面上,在卸荷成拉之前,在压缩保持区内观察到显著的结构演化。观察到晶界牵引力大小与激波方向有很强的角依赖性。非施密德效应继续表明它们对微观结构缺陷类型向成核空洞的倾向有影响。利用概率论提出了一个通用的空洞成核判据。本文以弱激波条件下的多晶BCC钽为研究对象,包括晶界空洞成核强度的SVE计算和文献分子动力学计算。利用概率密度函数描述了局部应力状态非均质性与分布晶界空洞成核强度状态之间的相互作用。因果熵最大化过程消除了特别选择PDF功能表单的要求,并为基于数据的PDF确定提供了严格的过程。由此产生的物理信息PDF描述了成核空洞的空间出现频率,作为施加宏观尺度压力的函数。因此,较低长度尺度的物理被封装在一个精确的和计算有效的方式,提供计算塑性洞察宏观尺度的动态延性损伤模型。
Local buckling behaviour and CSM-based improved design method for high strength steel tubular beam-columns
Xuan Li, Xiaoyi Lan, Junbo Chen, Tak-Ming Chan
doi:10.1016/j.tws.2025.113232
高强钢管梁柱局部屈曲行为及基于csm的改进设计方法
This study aims to provide accurate and reliable resistance predictions for high strength steel (HSS) tubular beam-columns failing by local buckling, which are crucial for the economical and safe applications of HSS structures. Slender and non-slender circular, elliptical, rectangular and square hollow sections were studied. Relevant experimental results from the literature on cold-formed and hot-finished steel tubular sections were compiled. Given the limited availability of reported test results, extensive numerical simulations were conducted to cover broad ranges of steel grades, cross-section slenderness and loading eccentricities. When compared with the obtained test and numerical results, cross-section resistances predicted by the current design methods of European codes and American specifications were found to be considerably conservative and scattered. Hence, a new design approach was proposed, which uses the continuous strength method to determine the cross-section resistances under axial compression and pure bending, and adopts modified interaction curves for combined loading. The design proposals are shown to significantly improve the resistance prediction accuracy and consistency for the examined tubular sections under combined loading.
本研究旨在为高强度钢(HSS)管状梁柱局部屈曲破坏提供准确、可靠的抗力预测,这对HSS结构的经济、安全应用至关重要。研究了细长和非细长的圆形、椭圆形、矩形和方形空心截面。对冷弯和热加工钢管截面的相关实验结果进行了整理。考虑到报告的试验结果的有限可用性,进行了大量的数值模拟,以涵盖广泛的钢等级,截面长细比和加载偏心。通过与试验结果和数值计算结果的比较,发现现行欧美规范设计方法预测的截面阻力存在较大的保守性和分散性。为此,提出了一种新的设计方法,即采用连续强度法确定轴压和纯弯曲下的截面阻力,并采用修正的相互作用曲线进行组合加载。结果表明,该设计方案显著提高了组合荷载作用下管截面阻力预测的准确性和一致性。
Axial Performance of a New Self-Locking and Rapid-Unlocking Inter-Module Connection for Modular Steel Construction
Jun-Yi Lian, Wen-Yuan Zhang, Yu-Kun Ding, Andrew William Lacey, Wensu Chen
doi:10.1016/j.tws.2025.113202
一种新型自锁快速解锁模块间连接的轴向性能
Module-to-module connections are critical for assembly and disassembly efficiency of modular steel constructions, particularly for temporary modular buildings. However, existing module-to-module connections fail to meet the requirements of both Self-Locking and Rapid-Unlocking (SelRU) at the same time. To address this issue, this paper proposes an innovative SelRU inter-module connection featuring a self-locking mechanism inspired by door lock and a disassembly method using an unlocking tool inserted from the top of the modular column. Firstly, the assembly and disassembly processes were assessed using 3D-printed prototype and steel prototype. Three specimens with different loading protocols and heights of the lock cylinder were employed to investigate the axial performance of the proposed connection. The functional feasibility and efficiency during disassembly and reassembly were evaluated qualitatively and quantitatively. In addition, finite element models were developed and validated against the experimental results. The initiation and propagation of plastic deformation of the proposed connection under tension were revealed by analyzing the distribution and development of equivalent plastic strain at the specific points on the latch bolt and lock cylinder. Then, the effect of steel grade and diameter of lock cylinder, height of strike plate, width of latch bolt, thickness and steel grade of upper end plate on the nominal yield load, ultimate load and the stiffness of the SelRU connection under tension were discussed. Finally, a theoretical model of the proposed connection under tensile load was developed and validated against experimental and numerical results.
模块间的连接对于模块化钢结构的组装和拆卸效率至关重要,特别是对于临时模块化建筑。但是,现有的模块对模块连接不能同时满足自锁和快速解锁(SelRU)的要求。为了解决这个问题,本文提出了一种创新的SelRU模块间连接,其特点是受门锁启发的自锁机制和使用从模块柱顶部插入的解锁工具的拆卸方法。首先,使用3d打印原型和钢制原型对装配和拆卸过程进行了评估。采用不同加载方式和锁紧筒高度的三个试件来研究所提出的连接的轴向性能。定性和定量地评价了拆卸和重组过程中功能的可行性和效率。建立了有限元模型,并对实验结果进行了验证。通过分析锁紧螺栓和锁紧筒上特定点等效塑性应变的分布和发展,揭示了该连接在拉伸作用下塑性变形的产生和扩展过程。然后,讨论了锁紧筒的钢种和直径、打击板的高度、锁紧螺栓的宽度、上端板的厚度和钢种对SelRU连接的名义屈服载荷、极限载荷和受拉刚度的影响。最后,建立了该连接在拉伸荷载作用下的理论模型,并通过实验和数值结果进行了验证。
Fundamental mathematical model on nonlinear non-symmetric free vibration of thin circular plate carrying concentrated masses
Desheng Li, Baowang Huang, Jiangtao Yu
doi:10.1016/j.tws.2025.113208
承载集中质量的薄板非线性非对称自由振动的基本数学模型
This paper is concerned with the fundamental mathematical model on nonlinear non-symmetric free vibration of thin circular plate carrying concentrated masses. Firstly, a novel deflection trial function compounded by Chebyshev polynomials and Trigonometric series is employed. Vibration of the plate is modeled as a Duffing's equation via solving the total stress function by point-matching method. Furthermore, four kinds of point-matching strategies, including two strategies (EPS and RCPS) completely disregard the effect of the concentrated mass and the other two strategies (MEPS and MRCPS) take the effect into account, are designed to solve the Duffing's equation. Result of nonlinear frequency from small-vibrations approximation shows that values of strategies MEPS and MRCPS coincide with the published datum better. At last, effect of the concentrated mass on the dimensionless period, nonlinear frequency and the coefficients of Duffing's equation is researched. Only the cubic stiffness coefficient is affected by the point-matching strategies. The linear stiffness coefficient and the differential coefficient depend completely on the deflection trial function, the structure of the plate and the parameters of the concentrated mass. This paper not only expanded the point-matching method but also provided a powerful tool for the nonlinear non-symmetric vibrating mathematical model of titled structure.
本文研究了承载集中质量的薄板非线性非对称自由振动的基本数学模型。首先,采用一种由切比雪夫多项式和三角级数复合而成的挠度试函数。通过点匹配法求解总应力函数,将板的振动建模为Duffing方程。此外,设计了四种点匹配策略,其中两种策略(EPS和RCPS)完全忽略了集中质量的影响,另外两种策略(MEPS和MRCPS)考虑了集中质量的影响,以求解Duffing方程。由小振动近似得到的非线性频率结果表明,MEPS和MRCPS策略的值与已发表的数据吻合较好。最后,研究了集中质量对无量纲周期、非线性频率和Duffing方程系数的影响。只有三次刚度系数受点匹配策略的影响。线性刚度系数和微分系数完全取决于挠度试验函数、板的结构和集中质量的参数。本文不仅对点匹配方法进行了扩展,而且为标题结构非线性非对称振动数学模型的建立提供了有力的工具。
Crashworthiness analysis of single CFRP, hybrid CFRP/Al and fiber metal laminate C-channels: Quasi-static crushing tests and numerical simulations
Haolei Mou, Yingshi Chen, Jiang Xie, Haibao Liu
doi:10.1016/j.tws.2025.113226
单一CFRP、复合CFRP/Al和金属纤维层压板c通道的耐撞性分析:准静态破碎试验和数值模拟
To investigate the crashworthiness and failure mechanisms of carbon fiber reinforced plastic (CFRP) and Aluminum (Al) C-channels for aircraft applications, the single CFRP, hybrid CFRP/Al and fiber metal laminates (FML) C-channels with hybrid constitution modes are fabricated, and quasi-static axial crushing tests are conducted. The crush-related failure mechanisms are also characterized by an effectively combined interface and comparative studies between hybrid CFRP/Al structures and FML structures, which have not been thoroughly explored in previous research. Generalized Incremental Stress State Dependent Damage Model (GISSMO) for Al, integrating intralaminar and interlaminar damage models for CFRP, are developed to numerically investigate with 5.55 % maximum difference. The results show that FML C-channels effectively absorb the maximum 1289.34 J crushing energy through the progressive failure modes, with a 60.58 % increase over that of single CFRP C-channels. The position of the net Al C-channel with inwards migration from the central location has an adverse effect on the C-channel, and the EA and SEA are decreased by 17.56 % and 17.49 %, respectively. As the hybrid ratio of the net CFRP increases, the SEA and EA become mutually competitive. When the hybrid ratio of the net CFRP reached 67 %, the EA and SEA increased by 60.11 % and 16.20 %, respectively. In addition, the interfaces between the net CFRP and Al could indicate crashworthiness and damage extent, which remains basically consistent with the overall trends when the number of effective combined interfaces changed. The FML C-channels offer novel configurations for the sub-cargo columns to improve aircraft crashworthiness.
为研究飞机用碳纤维增强塑料(CFRP)和铝(Al) c型通道的耐撞性和破坏机理,制备了具有混合本构模式的CFRP、CFRP/Al复合材料和金属纤维层压板(FML) c型通道,并进行了准静态轴向破碎试验。CFRP/Al复合结构与FML复合结构具有有效结合界面和对比研究的特点,这是以往研究中尚未深入探讨的。综合CFRP的层内和层间损伤模型,建立了Al的广义增量应力状态相关损伤模型(GISSMO),以5.55%的最大差异进行数值研究。结果表明:FML c通道通过递进破坏模式有效吸收的破碎能量最大可达1289.34 J,比单个CFRP c通道增加60.58%;净Al -c通道的位置从中心位置向内迁移对c通道有不利影响,EA和SEA分别降低了17.56%和17.49%。随着净碳纤维复合材料混合比例的增加,SEA和EA相互竞争。当净CFRP混杂比达到67%时,EA和SEA分别增加了60.11%和16.20%。此外,净CFRP与Al之间的界面可以指示耐撞性和损伤程度,这与有效组合界面数量变化时的总体趋势基本一致。FML c通道为副货物柱提供了新的配置,以提高飞机的耐撞性。