European Journal of Mechanics A-Solids最新文献_第3页

Modelling lateral spread in wire flat rolling 线材轧制横向扩展的建模

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-12 DOI: 10.1016/j.euromechsol.2026.106027

Mozhdeh Erfanian , Carl D. Slater , Edward J. Brambley

A mathematical model for wire rolling is developed, focusing on predicting the lateral spread. This provides, for the first time, an analytic model of lateral spread without any fitting parameters. The model is derived directly from the governing equations, assuming a rigid, perfectly plastic material and exploiting the thinness of the wire (in thickness and width) relative to the roller size. Results are compared against experiments performed on stainless steel wire using

100 mm

diameter rolls, demonstrating accurate predictions of lateral spread across a wide range of wire diameters (

2.96 mm

–

7.96 mm

) and reduction ratios (20%–60%), all without the need for fitting parameters. Since the model requires only seconds to compute, the model’s valid range is explored for varying roll diameter, wire diameter, and reduction ratio, and their effects on the resulting lateral spread characterised. The model can serve as a robust tool for validating FE results, guiding process design, and laying the foundation for future improved models. Matlab code to evaluate the model is provided in the supplementary material.

建立了线材轧制的数学模型，重点研究了线材横向扩展的预测。这首次提供了一个没有任何拟合参数的横向扩散的解析模型。该模型直接从控制方程中推导出来，假设材料是刚性的、完全塑性的，并利用线材的细度（厚度和宽度）相对于辊的尺寸。结果与使用直径为100mm的轧辊在不锈钢丝上进行的实验进行了比较，证明了在很宽的丝径范围内（2.96mm-7.96mm）的横向扩散和减速率（20%-60%）的准确预测，所有这些都不需要拟合参数。由于该模型只需要几秒钟的计算时间，因此该模型的有效范围是针对不同的轧辊直径、线材直径和减速比，以及它们对产生的横向扩散特性的影响进行探索的。该模型可以作为验证有限元结果、指导过程设计以及为未来改进模型奠定基础的强大工具。在补充资料中提供了对模型进行评估的Matlab代码。

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引用次数: 0

Integration of active learning and MCMC sampling for efficient Bayesian calibration of mechanical properties 基于主动学习和MCMC采样的机械性能贝叶斯校正集成

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-12 DOI: 10.1016/j.euromechsol.2026.106015

Leon Riccius , Iuri B.C.M. Rocha , Joris Bierkens , Hanne Kekkonen , Frans P. van der Meer

Recent advancements in Markov chain Monte Carlo (MCMC) sampling and surrogate modelling have significantly enhanced the feasibility of Bayesian analysis across engineering fields. However, the selection and integration of surrogate models and cutting-edge MCMC algorithms, often depend on ad-hoc decisions. A systematic assessment of their combined influence on accuracy and efficiency is notably lacking. The present work offers a comprehensive comparative study, employing a scalable case study in computational mechanics focused on the inference of spatially varying material parameters, that sheds light on the impact of methodological choices for surrogate modelling and sampling. We show that a priori training of the surrogate model introduces large errors in the posterior estimation even in low to moderate dimensions. We introduce a simple active learning strategy based on the path of the MCMC algorithm that is superior to all a priori trained models, and determine its training data requirements. We demonstrate that the choice of the MCMC algorithm has only a small influence on the amount of training data but no significant influence on the accuracy of the resulting surrogate model. Further, we show that the accuracy of the posterior estimation largely depends on the surrogate model, but not even a tailored surrogate guarantees convergence of the MCMC. Finally, we identify the forward model as the bottleneck in the inference process, not the MCMC algorithm. While related works focus on employing advanced MCMC algorithms, we demonstrate that the training data requirements render the surrogate modelling approach infeasible before the benefits of these gradient-based MCMC algorithms on cheap models can be reaped.

马尔可夫链蒙特卡罗（MCMC）采样和代理模型的最新进展显著提高了贝叶斯分析在工程领域的可行性。然而，代理模型和尖端MCMC算法的选择和集成通常依赖于特别的决策。显然缺乏对它们对准确性和效率的综合影响的系统评估。目前的工作提供了一个全面的比较研究，在计算力学中采用可扩展的案例研究，重点关注空间变化材料参数的推断，这揭示了替代建模和抽样方法选择的影响。我们表明，代理模型的先验训练甚至在低到中等维度的后验估计中引入了很大的误差。我们引入了一种基于MCMC算法路径的简单主动学习策略，该策略优于所有先验训练模型，并确定了其训练数据需求。我们证明了MCMC算法的选择对训练数据量的影响很小，但对生成的代理模型的准确性没有显著影响。此外，我们表明后验估计的准确性在很大程度上取决于代理模型，但即使是定制的代理也不能保证MCMC的收敛性。最后，我们将前向模型识别为推理过程中的瓶颈，而不是MCMC算法。虽然相关工作的重点是采用先进的MCMC算法，但我们证明，在获得这些基于梯度的MCMC算法在廉价模型上的好处之前，训练数据的需求使得代理建模方法不可行。

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引用次数: 0

Vibration analysis and vibration reduction strategy for an axially moving beam with a bistable nonlinear energy sinks 具有双稳非线性能量汇的轴向运动梁的振动分析与减振策略

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-12 DOI: 10.1016/j.euromechsol.2026.106029

Peng Chen , Ji-Hou Yang , Xiang-Ying Guo , Hua-Ting Liu , Xiao-Dong Yang

This study investigates the use of bistable nonlinear energy sinks (BNES) to suppress multimodal vibrations in axially moving beams. A coupled nonlinear dynamic model of the beam–BNES system is established and discretized using the Galerkin method. The beam's complex eigenfrequencies are analyzed to clarify the effects of axial speed and tensile load on flutter-induced instability. A continuation algorithm is then applied to compute the amplitude–frequency responses of the first two modes, with and without BNES coupling. Three BNES installation configurations are subsequently evaluated to identify the most effective vibration-control strategy. In addition, the influences of external excitation, axial velocity, tensile force, and the stiffness and damping parameters on suppression performance are systematically investigated. Based on the parametric analysis, a particle swarm optimization (PSO) algorithm is further employed to optimize the stiffness and damping parameters of the BNES, aiming to reduce the activation threshold while enhancing vibration suppression performance. The results show that distributing multiple BNES units along the beam provides superior multimode suppression compared with a single absorber. The BNES performance is sensitive to both axial motion and tensile load, and appropriate tuning of excitation level, stiffness, and damping within practical limits can further improve vibration-reduction efficiency.

本文研究了利用双稳态非线性能量汇（BNES）来抑制轴向运动梁的多模态振动。建立了梁- bnes系统的耦合非线性动力学模型，并用伽辽金方法进行了离散化。分析了梁的复特征频率，阐明了轴向速度和拉伸载荷对颤振失稳的影响。然后应用连续算法计算了前两种模态的幅频响应，包括有和没有BNES耦合。随后评估了三种BNES安装配置，以确定最有效的振动控制策略。此外，系统地研究了外部激励、轴向速度、拉力、刚度和阻尼参数对抑制性能的影响。在参数分析的基础上，进一步采用粒子群优化算法（PSO）对BNES的刚度和阻尼参数进行优化，在降低激活阈值的同时提高抑制振动的性能。结果表明，与单个吸收器相比，沿光束分布多个BNES单元具有更好的多模抑制效果。BNES的性能对轴向运动和拉伸载荷都很敏感，在实际范围内适当调整激励水平、刚度和阻尼可以进一步提高减振效率。

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引用次数: 0

An integrated fabrication process for reducing thermal distortion of the CFRP reflector surface 一种降低CFRP反射面热变形的集成制造工艺

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-10 DOI: 10.1016/j.euromechsol.2026.106025

Kangcheng Yin , Bo Yuan , Zhenyuan Xu , Zibo Sun , Qingchao Sun , Xiaokai Mu

Severe surface thermal distortion poses a significant challenge to the application of carbon fiber-reinforced polymer (CFRP) in lightweight reflectors. Minor deviations in the manufacturing process can lead to remarkable thermal deformation, hindering efforts to optimize fabrication techniques. This study investigates the impact mechanisms of process deviations during the layup and curing stages of CFRP reflector production on thermal distortion and introduces an integrated fabrication process that combines anti-symmetric folding layup with pre-curing technology. This innovative approach enhances the middle plane symmetry of the laminate, thereby significantly reducing thermal distortion on the surface of CFRP reflectors. Experimental samples were fabricated using the newly developed process and compared to those produced using conventional methods in terms of surface thermal distortion. The results demonstrate that, compared to the symmetric layup process, the integrated fabrication process achieves a 53.45 % reduction in the peak-to-valley value of surface thermal distortion, underscoring its significant prospect for advancing engineering applications.

严重的表面热变形对碳纤维增强聚合物（CFRP）在轻量化反射器中的应用提出了重大挑战。制造过程中的微小偏差可能导致显著的热变形，阻碍了优化制造技术的努力。本研究探讨了CFRP反射器在铺层和固化阶段的工艺偏差对热变形的影响机制，并介绍了一种将反对称折叠铺层与预固化技术相结合的集成制造工艺。这种创新的方法增强了层压板的中间平面对称性，从而显著减少了CFRP反射器表面的热变形。实验样品采用新开发的工艺制作，并在表面热变形方面与传统方法生产的样品进行了比较。结果表明，与对称铺层工艺相比，集成工艺使表面热畸变峰谷值降低了53.45%，具有重要的工程应用前景。

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引用次数: 0

Nonlinear fracture analysis of a penny-shaped crack in two-dimensional hexagonal piezoelectric quasicrystal media 二维六边形压电准晶介质中便士形裂纹的非线性断裂分析

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-09 DOI: 10.1016/j.euromechsol.2026.106020

Yuan Li , Shuhang Tang , Minghao Zhao , Jingli Ren

This study examines nonlinear fracture behavior for two-dimensional hexagonal piezoelectric quasicrystal media weakened by a penny-shaped crack. An electric polarization saturation model is developed for a penny-shaped crack in this material. The nonlinear fracture model is governed by a set of boundary integral-differential equations involving normal phonon displacement and electric potential discontinuities—collectively termed extended displacement discontinuities—as the variables to be determined. Analytical solutions of the extended displacement discontinuities, extended stress intensity factors and electric yielding zone are derived for uniformly applied electric and normal phonon loadings. Based on boundary element method and extended displacement discontinuity method, a numerical method for annular loadings is proposed to solve the boundary integral-differential equations. At the same time, we propose a numerical iterative method, which can effectively solve the size of electric yielding zone. Numerical results are utilized to cross-validate the obtained analytical solutions and the proposed numerical method. Graphical illustrations are provided to demonstrate the distributions of the key physical quantities obtained by the above two methods. The analytical and numerical solutions developed in this study offer effective methodologies for further investigations of other piezoelectric quasicrystals.

本文研究了二维六角形压电准晶介质的非线性断裂行为。建立了该材料便士型裂纹的电极化饱和模型。非线性断裂模型由一组边界积分微分方程控制，其中包括正常声子位移和电势不连续-统称为扩展位移不连续-作为待确定的变量。导出了均匀施加电声子和正常声子载荷时扩展位移不连续面、扩展应力强度因子和电屈服区的解析解。基于边界元法和扩展位移不连续法，提出了求解环空载荷边界积分-微分方程的数值方法。同时，我们提出了一种数值迭代方法，可以有效地求解电力屈服区的大小。数值结果对得到的解析解和提出的数值方法进行了交叉验证。提供了图形插图来演示通过上述两种方法获得的关键物理量的分布。本研究的解析解和数值解为进一步研究其他压电准晶体提供了有效的方法。

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引用次数: 0

Influence of shear stress on ductile failure initiation: a micromechanical analysis of strain localization 剪切应力对延性破坏起始的影响：应变局部化的微观力学分析

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-09 DOI: 10.1016/j.euromechsol.2026.106019

J.C. Zhu , M. Ben Bettaieb , F. Abed-Meraim , B. Jia , J. Li

Shear stress is recognized as a critical factor influencing the ductile failure process. In the present work, we investigate ductile failure initiation under shear-dominated loading by identifying the onset of strain localization, which is predicted using a rigorous bifurcation analysis. Micromechanical computations are performed using cubic voided unit cells (UCs) subjected to fully periodic boundary conditions. Proportional stressing is imposed to keep constant stress triaxiality (T) and Lode parameter (L) throughout the deformation history of UCs. In the proportional stressing, two loading configurations are realized to comparatively study the effect of shear stress component for a given pair of T and L: normal stresses (without shear) versus normal stresses combined with one shear stress component. The effects of initial porosity and void configuration (pattern of voids arrangement) are also systematically analyzed. The results show that the influence of shear stress is strongly modulated by the amount of the initial porosity. While shear stress promotes strain localization at low initial porosity, it conversely delays it at high initial porosity within a specific range of Lode parameters. This porosity-dependent trend reversal is rationalized by a transition from a ligament-thinning-dominated failure mode to an intervoid-shearing-dominated failure mode as the stress state varies. Furthermore, for a given overall initial porosity, the void configuration significantly affects the critical strain locus, the extent of which depends on the imposed triaxiality. These findings provide valuable micromechanical insights for refining predictive modeling in engineering applications.

剪切应力被认为是影响延性破坏过程的关键因素。在目前的工作中，我们通过识别应变局部化的开始来研究剪切主导载荷下的韧性破坏启动，这是使用严格的分岔分析来预测的。微力学计算采用立方空胞（UCs）进行全周期边界条件。在整个变形过程中，施加比例应力以保持应力三轴性(T)和Lode参数(L)不变。在比例应力下，实现了两种加载配置，对比研究了给定T和L对剪应力分量的影响：正应力（无剪应力）与正应力加一个剪应力分量。系统地分析了初始孔隙率和孔洞形态（孔洞排列模式）的影响。结果表明，剪切应力的影响受初始孔隙率的强烈调节。在Lode参数的特定范围内，剪切应力在低初始孔隙度条件下促进应变局部化，反之在高初始孔隙度条件下则延迟应变局部化。随着应力状态的变化，这种依赖于孔隙率的趋势逆转是合理的，从韧带变薄为主的破坏模式转变为间隙剪切为主的破坏模式。此外，对于给定的总体初始孔隙率，孔隙形态显著影响临界应变轨迹，其程度取决于所施加的三轴性。这些发现为改进工程应用中的预测建模提供了有价值的微力学见解。

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引用次数: 0

Parametric and multi-objective optimization analysis of cactus stem-inspired bionic multi-cell tubes for enhanced crashworthiness 仙人掌茎型仿生多细胞管抗撞性的参数化多目标优化分析

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-08 DOI: 10.1016/j.euromechsol.2026.106022

Daifeng Yang , Jianbo Chen , Yining Zhang , Perk Lin Chong , Eric Li

This study extends our previous research on the cactus stem-inspired bionic multi-cell tube (CSBMT) by conducting a deeper investigation aimed at further enhancing its crashworthiness performance. Finite element analysis (FEA) was employed to investigate the energy absorption performance of CSBMT under varying geometric parameters, including the number of corners (N), inner diameter (D_i), and outer angle (β). Additional analyses examined the influence of oblique loading (0°–30°) and gradient wall thickness distributions (n = 0.2–5.0). The results indicate that increasing N and D_i significantly improves the specific energy absorption (SEA), while a larger β and smaller n enhance load uniformity and deformation stability. Compared with the baseline configuration, the optimal design achieved a 74.9 % improvement in SEA. Compared with 16 classical thin-walled energy-absorbing structures, the CSBMT exhibited superior energy absorption and load-bearing capacity under 20° oblique loading. Furthermore, a multi-objective structural optimization of the CSBMT was performed using the Non-dominated Sorting Genetic Algorithm II (NSGA-II), and a compromise solution was identified based on the minimum distance criterion. The optimized structure exhibited a well-balanced performance between energy absorption efficiency and peak load control. The findings provide valuable insights for the design of bio-inspired energy-absorbing structures in crashworthiness applications.

本研究扩展了我们之前对仙人掌茎仿生多细胞管（CSBMT）的研究，进行了更深入的研究，旨在进一步提高其耐撞性能。采用有限元分析（FEA）研究了不同几何参数下CSBMT的吸能性能，包括角数(N)、内径（Di）和外角（β）。另外的分析检查了倾斜载荷（0°-30°）和梯度壁厚分布（n = 0.2-5.0）的影响。结果表明，增大N和Di可显著提高材料的比能吸收（SEA），增大β和减小N可提高材料的载荷均匀性和变形稳定性。与基线配置相比，优化设计的SEA提高了74.9%。与16种经典薄壁吸能结构相比，CSBMT在20°斜荷载作用下具有更好的吸能和承载能力。利用非支配排序遗传算法II （NSGA-II）对CSBMT进行了多目标结构优化，并基于最小距离准则找到了一个折衷解。优化后的结构在能量吸收效率和峰值负荷控制之间表现出良好的平衡。这一发现为设计抗碰撞应用的仿生吸能结构提供了有价值的见解。

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引用次数: 0

Nonlinear forced vibrations of FGM microplates: a numerical approach in the context of Mindlin's strain gradient elasticity FGM微板的非线性强迫振动：在Mindlin应变梯度弹性的背景下的数值方法

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-08 DOI: 10.1016/j.euromechsol.2026.106023

Y. Gholami , R. Ansari , H. Rouhi

This study aims to investigate the geometrically nonlinear forced vibration behavior of micro-scale plates made of functionally graded materials (FGMs) by developing a variational numerical approach that accounts for strain gradient effects. The proposed approach, which is based on the variational differential quadrature technique, is capable of addressing the problem with arbitrary geometry (e.g. quadrilateral plate, annular sector plate, triangular plate, etc.). Besides, Mindlin's strain gradient theory is applied that leads to a formulation which encompasses the modified versions of strain gradient and couple stress theories (MSGT & MCST). An important novelty of present work is its vector-matrix presentation which can be beneficial for researchers working on numerical methods. Based on Hamilton's principle together with Mindlin's plate theory, the governing equations are derived. In the numerical results, the effects of thickness-to-material length-scale parameter on the frequency-response curves of FG plates with various shapes are analyzed. Also, comparisons are made between the predictions of MCST, MSGT as well as the classical theory. The results indicate that strain gradient terms have a pronounced influence on the nonlinear dynamic response of FGM microplates, giving rise to evident stiffening behavior and noticeable changes in the frequency–response curves. These observations highlight the importance of using higher-order continuum models to achieve reliable predictions of nonlinear forced vibration behavior at the micro-scale.

本研究旨在通过发展考虑应变梯度效应的变分数值方法来研究由功能梯度材料（fgm）制成的微尺度板的几何非线性强迫振动行为。该方法基于变分微分正交技术，能够解决任意几何形状（如四边形板、环形扇形板、三角形板等）的问题。此外，采用Mindlin的应变梯度理论，得到了一个包含应变梯度和耦合应力理论（MSGT &； MCST）修正版本的公式。当前工作的一个重要新颖之处在于它的向量矩阵表示，这对研究数值方法的研究人员是有益的。根据汉密尔顿原理和明德林的平板理论，推导了控制方程。数值结果分析了不同形状FG板的厚度-材料长度尺度参数对频率响应曲线的影响。并对MCST、MSGT和经典理论的预测结果进行了比较。结果表明，应变梯度项对FGM微孔板的非线性动态响应有显著影响，使其出现明显的加筋行为，频率响应曲线发生明显变化。这些观察结果强调了使用高阶连续体模型在微观尺度上实现非线性强迫振动行为可靠预测的重要性。

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引用次数: 0

A deep learning approach to predict cyclic softening behaviour of irradiated and non-irradiated RAFM steels under low cycle fatigue 一种预测辐照和非辐照RAFM钢低周疲劳循环软化行为的深度学习方法

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-08 DOI: 10.1016/j.euromechsol.2026.106021

Hussein Zahran , Aleksandr Zinovev , Dmitry Terentyev , Ali Aouf , Magd Abdel Wahab

Qualification of Reduced Activation Ferritic-Martensitic (RAFM) steels for fusion reactors require Low Cycle Fatigue (LCF) testing including experiments after irradiation. Cyclic softening curves from these tests help reduce the conservatism of RCC-MRx. In this work, Deep Neural Network (DNN) is used to predict the cyclic softening curves for irradiated and non-irradiated RAFM steels. Cyclic softening for specimens tested under different conditions are gathered from literature. Three samples are used in this study with increased number of points obtained per curve. The results showed that increasing the number of points per curve reduced the overfitting of the training set. This is shown through the increase of the accuracy scores for both the validation and prediction sets. SHapley Additive exPlanation (SHAP) analysis is performed to understand how the DNN model interprets the effect of the input features on the output. The DNN model with the tuned hyperparameters is used to predict the cyclic softening curves of the prediction sets. The curves show very good agreement between the experimental and predicted curves for both irradiated and non-irradiated material.

用于聚变反应堆的低活化铁素体-马氏体（RAFM）钢的鉴定需要低周疲劳（LCF）测试，包括辐照后的试验。这些试验的循环软化曲线有助于降低RCC-MRx的保守性。本文采用深度神经网络（Deep Neural Network， DNN）预测辐照和未辐照RAFM钢的循环软化曲线。不同试验条件下试件的循环软化数据来源于文献。本研究中使用了三个样本，每条曲线获得的点数量增加。结果表明，增加每条曲线的点数减少了训练集的过拟合。这可以通过验证集和预测集的准确性分数的增加来证明。SHapley加性解释（SHAP）分析是为了理解DNN模型如何解释输入特征对输出的影响。采用超参数调优后的深度神经网络模型对预测集的循环软化曲线进行预测。辐照和未辐照物质的实验曲线和预测曲线吻合得很好。

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引用次数: 0

Shot-peening simulations with artificial surface defect using multiple impacts and eigenstrain reconstruction method 基于多重冲击和特征应变重建方法的人工表面缺陷喷丸模拟

IF 4.2 2区工程技术 Q1 MECHANICS

European Journal of Mechanics A-Solids

Pub Date : 2026-01-08 DOI: 10.1016/j.euromechsol.2026.106018

Monzer Daoud , Régis Kubler

Shot-peening is a surface treatment process widely employed to enhance the fatigue life of metallic components by inducing compressive residual stresses beneath the surface. However, such components often contain surface or subsurface geometrical defects that can reduce fatigue life. Accurate understanding of the resulting residual mechanical fields near these defects is essential for integrating shot-peening into the design process and accurately predicting the fatigue life. This study investigates the evolution of residual mechanical fields both near and far from an artificial hole (800 μm in diameter and 400 μm in depth), as well as the associated edge-hole distortion after shot-peening. A finite element framework was employed to compare two approaches: a multi-impact shot-peening model and an eigenstrain reconstruction method incorporating elastoplastic behavior. Both approaches were applied to TRIP780 steel, using experimental material parameters as inputs and experimental residual stress profiles for validation. Results showed that the multi-impact shot-peening model successfully simulated the localized plastic deformation adjacent to the hole, where strain concentration and distortion extended up to 200 μm from the edge. Although the eigenstrain method could not reproduce the edge-hole distortion, it generated comparatively similar localized plastic deformation near the hole and provided accurate residual stress predictions at distances beyond 200 μm from the hole, owing to inputs from the multi-impact shot-peening model. Both approaches indicated that the radial stresses were more influenced by the hole than the tangential ones.

喷丸是一种广泛应用的表面处理工艺，通过在表面下产生残余压应力来提高金属构件的疲劳寿命。然而，这些部件通常含有表面或表面下的几何缺陷，会降低疲劳寿命。准确了解这些缺陷附近产生的残余力学场对于将喷丸强化纳入设计过程和准确预测疲劳寿命至关重要。研究了人工喷丸孔（直径800 μm，深度400 μm）附近和远处残余力学场的演变，以及喷丸后相关的边缘变形。采用有限元框架对两种方法进行了比较：多冲击喷丸模型和考虑弹塑性行为的特征应变重建方法。这两种方法都应用于TRIP780钢，使用实验材料参数作为输入和实验残余应力剖面进行验证。结果表明：多冲击喷丸模型成功地模拟了孔附近的局部塑性变形，应变集中和变形从边缘延伸至200 μm；虽然特征应变法不能再现孔边变形，但由于多冲击喷丸模型的输入，该方法在孔附近产生了相对相似的局部塑性变形，并在距孔200 μm以上的距离上提供了准确的残余应力预测。两种方法均表明，径向应力受孔洞的影响大于切向应力。

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引用次数: 0