International Journal of Fatigue最新文献_第4页

Enhancing fatigue life of L12-strengthened multi-principal element alloy by tailoring grain boundary characteristics and precipitation 通过调整晶界特征和析出来提高l12强化多主元素合金的疲劳寿命

IF 6 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-30 DOI: 10.1016/j.ijfatigue.2026.109523

Shaoxin Cai, Jingping Cui, Baijun Yang, Dong Han, Jianqiang Wang

引用次数: 0

The effects of austempering time on mechanical properties of the novel GCr15Si1MoNbV bearing steel and on its rolling contact fatigue behaviors 等温回火时间对新型GCr15Si1MoNbV轴承钢力学性能及滚动接触疲劳行为的影响

IF 6 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-28 DOI: 10.1016/j.ijfatigue.2026.109519

Yanhui Wang, Ziqi Liu, Xubiao Wang, Xiang Chen, Xiliang Zhang, Wenfei Shen, Qian Yang, Leijie Zhao, Zhinan Yang

引用次数: 0

Defect-based multiaxial fatigue life assessment of 3D-printed bulk metallic glasses 基于缺陷的3d打印大块金属玻璃多轴疲劳寿命评估

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-27 DOI: 10.1016/j.ijfatigue.2026.109528

Songyun Ma , Hongshi Ruan , Jianye Shi , Cécile Chaxel , Shuai Wei , Moritz Stolpe , Peilei Zhang , Yangjian Xu , Bernd Markert

Additive manufacturing unlocks near-net-shape production of bulk metallic glass (BMG) components with complex geometries. Nevertheless, their durability under multiaxial cyclic loadings remains largely unexplored and poorly understood. In this work, the multiaxial fatigue behaviour of selective laser melting (SLM) fabricated Zr-based BMG with composition

{Zr}_{59.3} {Cu}_{28.8} {Nb}_{1.5} {Al}_{10.4}

is investigated. In multiaxial fatigue experiments, 17 specimens with approximately 0.46% porosity were subjected to stress-controlled cyclic loadings, including both proportional and non-proportional loading paths. The fracture morphology and multiaxial fatigue mechanisms were systematically analysed using SEM micrographs. To evaluate the fatigue life of 3D-printed BMGs while accounting for manufacturing-induced defects, we conducted defect-based computational simulations using representative volume element (RVE) models incorporating a single pore defect. Parametric studies were carried out to examine the influence of pore location on multiaxial fatigue life performance. Based on the FEM simulation results, a modified non-local Dang Van criterion is proposed for predicting the multiaxial fatigue life. In the critical plane model, a non-proportional correction coefficient is introduced based on the principal stress at the critical location in the vicinity of the defect to enhance the prediction accuracy. The results demonstrate that the proposed model can predict the multiaxial fatigue life of 3D-printed BMG with satisfactory accuracy.

增材制造解锁了具有复杂几何形状的大块金属玻璃（BMG）组件的近净形状生产。然而，它们在多轴循环载荷下的耐久性在很大程度上仍未被探索和了解。研究了选择性激光熔化zr59 .3 cu28 .8 nb1.5 . al10.4 zr基BMG的多轴疲劳行为。在多轴疲劳试验中，选取17个孔隙率约为0.46%的试件进行应力控制循环加载，包括比例加载路径和非比例加载路径。利用扫描电镜对断口形貌和多轴疲劳机理进行了系统分析。为了评估3d打印bmg的疲劳寿命，同时考虑到制造引起的缺陷，我们使用包含单孔缺陷的代表性体积元（RVE）模型进行了基于缺陷的计算模拟。通过参数化研究考察了孔隙位置对多轴疲劳寿命性能的影响。在有限元模拟结果的基础上，提出了一种改进的非局部Dang Van准则来预测多轴疲劳寿命。在临界平面模型中，根据缺陷附近临界位置的主应力引入非比例修正系数，提高了预测精度。结果表明，该模型能较好地预测3d打印BMG的多轴疲劳寿命。

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引用次数: 0

A 2.9 GPa modified M50 steel with Remarkably high fatigue strength by Nb and Al alloying 采用Nb和Al合金化改性了一种GPa为2.9的M50钢，具有很高的疲劳强度

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-27 DOI: 10.1016/j.ijfatigue.2026.109518

Jing Zhang , Qingfeng Kang , Hui Wang , Zexi Zhang , Wenquan Cao

Coarse prior austenite grains and large primary carbides are the main reasons for the limited strength and poor fatigue performance of M50 steel. In this study, the addition of Nb and Al to M50 steel was designed, leading to the simultaneous refinement of both the prior austenite grains (to 8.55 ± 0.58 μm) and the largest primary carbides (to 20 μm). Furthermore, the modified steel exhibited extremely excellent tensile strength (R_m: 2864 ± 49 MPa and R_p0.2: 2502 ± 22 MPa) and rotating bending fatigue strength (R_-1 = 1153 MPa). Microstructural characterization further revealed that alloying with Nb and Al synergistically altered the precipitation sequence during tempering, which suppressed Fe₃C precipitation and spheroidization, and instead promoted the formation of a dense and uniform distribution of nanoscale M₂C carbides, thereby significantly enhancing the tensile strength. Additionally, the Nb and Al alloying refined the primary MC and M₂C carbides by inhibiting eutectic reactions and promoting the high-temperature decomposition of eutectic carbides. Consequently, this pronounced carbide refinement shifted fatigue crack initiation away from the carbide-dominated fracture sites (typical of conventional M50 steel) to weak microstructural regions within the modified steel’s matrix, thereby markedly increasing fatigue strength. These weak structures were associated with local chemical inhomogeneities and strain concentration at martensite packets and blocks boundaries. In summary, this systematic investigation into the effects of Nb and Al alloying on the microstructure evolution, mechanical properties, and fatigue behavior of M50 steel offers a promising strategy for developing high-temperature bearing steels with ultrahigh strength and excellent fatigue performance.

粗的奥氏体晶粒和大的初生碳化物是造成M50钢强度有限、疲劳性能差的主要原因。在本研究中，设计了在M50钢中添加Nb和Al的方法，使先前的奥氏体晶粒（细化到8.55 ± 0.58 μm）和最大的初生碳化物（细化到20 μm）同时细化。此外,修改后的钢表现出非常优秀的抗拉强度(Rm: 2864 ± 49 MPa和Rp0.2: 2502 ± 22 MPa)和旋转弯曲疲劳强度(r 1 = 1153 MPa)。显微组织表征进一步表明，Nb和Al的合金化协同改变了回火过程中的析出顺序，抑制了Fe3C的析出和球化，促进了致密均匀分布的纳米级M2C碳化物的形成，从而显著提高了抗拉强度。Nb和Al合金通过抑制共晶反应和促进共晶碳化物的高温分解来细化初生MC和M2C碳化物。因此，这种明显的碳化物细化将疲劳裂纹的起裂点从碳化物主导的断裂部位（典型的传统M50钢）转移到改性钢基体内的弱显微组织区域，从而显著提高了疲劳强度。这些弱结构与局部化学不均匀性和马氏体包和块边界的应变浓度有关。综上所述，本文系统研究了Nb和Al合金对M50钢组织演变、力学性能和疲劳行为的影响，为开发具有超高强度和优异疲劳性能的高温轴承钢提供了有希望的策略。

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引用次数: 0

Plastic strain energy-based corrosion fatigue crack propagation modeling in 18Ni (250) welded joints 基于塑性应变能的18Ni（250）焊接接头腐蚀疲劳裂纹扩展模型

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-26 DOI: 10.1016/j.ijfatigue.2026.109516

Yongmei Zhu , Dan Meng , Xilu Zhao

Corrosion fatigue crack propagation (CFCP) in welded joints of deep-sea structures governs their structural integrity under prolonged exposure to aggressive marine environments. To address this, this study investigates CFCP in 18Ni (250) maraging steel welded joints by establishing a crack growth rate model driven by plastic strain energy. Four specimens were fabricated and underwent fatigue testing in simulated seawater (3.5% NaCl solution), quantifying crack growth life at stress ratios of 0.1 and 0.3. Digital image correlation characterized crack-tip cyclic plastic zone evolution, revealing strain/stress amplitudes and plastic strain energy distributions. Cyclic plastic zone behavior was analyzed to derive plastic strain energy, forming the basis of a CFCP rate model. Numerical simulations of crack growth aligned closely with experimental results (≤3.84% deviation). The model enables damage tolerance assessment for large-scale welded structures operating in corrosive environments.

深海结构焊接接头的腐蚀疲劳裂纹扩展（CFCP）决定了其长期暴露在恶劣海洋环境中的结构完整性。为了解决这一问题，本研究通过建立由塑性应变能驱动的裂纹扩展速率模型，对18Ni（250）马氏体时效钢焊接接头中的CFCP进行了研究。制作4个试件，在模拟海水（3.5% NaCl溶液）中进行疲劳试验，量化应力比为0.1和0.3时裂纹扩展寿命。数字图像相关表征了裂纹尖端循环塑性区演化，揭示了应变/应力幅值和塑性应变能分布。分析了循环塑性区行为，推导了塑性应变能，为CFCP速率模型奠定了基础。裂纹扩展数值模拟与实验结果吻合较好（偏差≤3.84%）。该模型能够对腐蚀性环境下的大型焊接结构进行损伤容限评估。

引用次数: 0

An energy-based physics–data fusion model for thermomechanical fatigue life prediction of directionally solidified superalloys 基于能量的定向凝固高温合金热-机械疲劳寿命预测物理-数据融合模型

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-25 DOI: 10.1016/j.ijfatigue.2026.109521

Jundong Wang , Yuanmin Tu , Song Wu , Pengfei He , Zhixun Wen

This study investigates the thermomechanical fatigue (TMF) behaviour and life prediction of directionally solidified nickel-based superalloys under different mechanical stress levels. TMF tests were first performed to obtain cyclic stress–strain responses and fatigue lives, and the associated fracture surfaces and microstructural evolution were characterised to identify the dominant damage and failure mechanisms at different stages. On this basis, a thermo-mechanically coupled TMF constitutive model incorporating anisotropic yielding and damage evolution was established. The classical Zamrik energy model was subsequently modified by embedding a nonlinear damage evolution law into the energy framework, introducing the viscoplastic energy dissipated per cycle as the driving variable, and explicitly accounting for the effects of phase angle and temperature, thereby yielding an energy-based TMF life-prediction relation. In parallel, a Transformer–LSTM network was constructed to learn a nonlinear mapping from multivariate time-series data to life-related features. Building on these developments, an energy-driven physics–data fusion life-prediction approach was proposed, in which the energy parameter predicted by the data-driven model is supplied to the modified Zamrik model for TMF life assessment. The results show that, under various loading conditions, most lives predicted by the fusion model fall within a two-fold dispersion band about the experimental data, with a generally conservative bias. The proposed approach combines high prediction accuracy with clear physical interpretability and provides a promising tool for TMF life evaluation and engineering design of nickel-based superalloy components.

研究了定向凝固镍基高温合金在不同机械应力水平下的热疲劳行为和寿命预测。首先进行TMF试验以获得循环应力-应变响应和疲劳寿命，并对相关断口表面和微观组织演变进行表征，以确定不同阶段的主要损伤和破坏机制。在此基础上，建立了考虑各向异性屈服和损伤演化的热-力耦合TMF本构模型。随后，对经典的Zamrik能量模型进行修正，将非线性损伤演化规律嵌入能量框架，引入每循环耗散的粘塑性能量作为驱动变量，并明确考虑相角和温度的影响，从而得到基于能量的TMF寿命预测关系。同时，构建了Transformer-LSTM网络，学习多变量时间序列数据到生命相关特征的非线性映射。在此基础上，提出了一种能量驱动的物理-数据融合寿命预测方法，将数据驱动模型预测的能量参数提供给改进的Zamrik模型，用于TMF寿命评估。结果表明，在不同的载荷条件下，核聚变模型预测的寿命与实验数据在两倍频散范围内，具有普遍的保守偏差。该方法具有较高的预测精度和清晰的物理可解释性，为镍基高温合金部件的TMF寿命评估和工程设计提供了一种有前景的工具。

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引用次数: 0

Redefining stress triaxiality for ultra-low cycle fatigue of structural steels 结构钢超低周疲劳应力三轴性的重新定义

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-25 DOI: 10.1016/j.ijfatigue.2026.109520

Qun He , Michael C.H. Yam , Xue-Mei Lin , H.C. Ho , Kwok-Fai Chung

Stress triaxiality has been a cornerstone parameter for describing void growth and ductile fracture in metals for more than 60 years. Its classical definition, derived from

J_{2}

plasticity without accounting for backstress, becomes inadequate in ultra-low cycle fatigue conditions, where backstress evolution and load reversals significantly alter the stress state. In such cases, the conventional definition of stress triaxiality may even lead to singularities when the second invariant of deviatoric stress, i.e.,

J_{2}

, approaches zero. This study revisits the classical void growth problem and demonstrates that the definition of stress triaxiality is inherently dependent on the adopted plasticity model. Specifically, once backstress is included in cyclic plasticity, it must also be accounted for in the definition of stress triaxiality to maintain consistency. In this way, a new definition of stress triaxiality incorporating the effect of backstress is proposed, providing a physically meaningful measure of stress triaxiality under cyclic loading. The new definition is analytically derived and validated through ultra-low cycle fatigue (ULCF) experiments of high-strength steel Q690, supported by finite element simulations. Results show that the proposed definition reliably captures the stress state associated with void growth and accurately predicts ULCF crack initiation life, overcoming the limitations of the classical definition. These findings establish, for the first time, a consistent theoretical and experimental basis for extending void-based fracture models to cyclic loading, with direct implications for assessing the seismic safety of steel structures.

60多年来，应力三轴性一直是描述金属中空洞生长和韧性断裂的基础参数。它的经典定义是从J2塑性推导而来，没有考虑回应力，在超低周疲劳条件下变得不充分，在超低周疲劳条件下，回应力演化和载荷反转会显著改变应力状态。在这种情况下，当偏应力的第二个不变量J2趋近于零时，应力三轴性的传统定义甚至可能导致奇点。该研究回顾了经典的空洞生长问题，并证明应力三轴性的定义本质上依赖于所采用的塑性模型。具体来说，一旦回应力被纳入循环塑性，它也必须在应力三轴性的定义中考虑，以保持一致性。通过这种方式，提出了包含背应力影响的应力三轴性的新定义，为循环加载下的应力三轴性提供了一种物理上有意义的测量方法。通过高强度钢Q690的超低周疲劳试验，结合有限元模拟，对新定义进行了解析推导和验证。结果表明，该定义可靠地捕捉了与孔洞扩展相关的应力状态，并准确地预测了ULCF裂纹起裂寿命，克服了经典定义的局限性。这些发现首次为将基于孔洞的断裂模型扩展到循环荷载建立了一致的理论和实验基础，对评估钢结构的抗震安全性具有直接意义。

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引用次数: 0

Fatigue resistance of stainless steel bolts under tension 不锈钢螺栓在拉力作用下的抗疲劳性能

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-23 DOI: 10.1016/j.ijfatigue.2026.109515

Lukas Ehrhardt, Natalie Stranghöner

Bolted connections made of stainless steel are increasingly used in cyclic loading applications. The design rules according to the current version of the first generation of EN 1993-1-9 were historically developed for carbon steel bolts and apply equally to stainless steel bolts, although the material properties of carbon and stainless steel bolts differ significantly. Furthermore, the fatigue resistance of stainless steel bolts is almost unknown. In the draft of the second generation of EN 1993-1-9, FprEN 1993-1-9, design rules for stainless steel bolts are not specified anymore.

For this reason, fatigue tests under constant amplitude loading under tension were conducted with bolts M16, M20, M24 and M36 according to EN ISO 4014/4017 made of austenitic stainless steel (A2 and A4) and austenitic-ferritic (duplex) stainless steel (D4, D6 and D8) with property classes 70, 80 and 100. In total, 175 fatigue tests under constant amplitude loading under tension were performed in accordance with DIN 969.

The fatigue tests showed that the investigated stainless steel bolts achieve higher fatigue resistances than specified by the detail category according to EN 1993-1-9, so that the specified fatigue resistance is conservative. Based on the results, modifications of the detail categories for stainless steel bolts and rods are proposed, which allow a more economical design. The results of this investigation have already been proposed for an early amendment to FprEN 1993-1-9. This paper provides background information of the proposed modifications.

不锈钢螺栓连接越来越多地用于循环加载应用。根据第一代EN 1993-1-9当前版本的设计规则，历史上是为碳钢螺栓开发的，同样适用于不锈钢螺栓，尽管碳螺栓和不锈钢螺栓的材料性能有很大不同。此外，不锈钢螺栓的抗疲劳性能几乎是未知的。在第二代en1993 -1-9、FprEN 1993-1-9的草案中，不再规定不锈钢螺栓的设计规则。为此，根据EN ISO 4014/4017标准，用性能等级为70、80和100的奥氏体不锈钢（A2和A4）和奥氏体-铁素体（双相）不锈钢（D4、D6和D8）制作的螺栓M16、M20、M24和M36进行了恒幅载荷下的拉伸疲劳试验。根据DIN 969，总共进行了175次恒幅载荷下的拉伸疲劳试验。疲劳试验表明，所研究的不锈钢螺栓的抗疲劳性能高于en1993 -1-9细部分类规定的抗疲劳性能，因此规定的抗疲劳性能是保守的。在此基础上，提出了对不锈钢螺栓和杆的细部分类进行修改的建议，使设计更加经济。这项调查的结果已被提议尽早修订FprEN 1993-1-9。本文提供了拟议修改的背景资料。

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引用次数: 0

Bayesian model updating and model validation for fatigue life prediction of additively manufactured aluminum alloys 增材制造铝合金疲劳寿命预测的贝叶斯模型更新与模型验证

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-23 DOI: 10.1016/j.ijfatigue.2026.109501

Zhanhua Liang , Jingwen Song , Feifan Li , Xianmin Chen , Jihong Zhu , Weihong Zhang

Fatigue life prediction for additively manufactured aluminum alloys is challenging due to limited data and significant material scatter. To address this, this study proposes a Bayesian uncertainty quantification framework for probabilistic prediction and model selection. Fatigue experiments were conducted on Laser Powder Bed Fusion (LPBF) AlSi10Mg specimens under two build directions. Bayesian inference was employed to update the parameters of four candidate models, characterizing data scarcity in the form of prediction uncertainty. U-pooling and Model Evidence metrics were then utilized to quantitatively evaluate model performance. The proposed framework effectively generated 95% confidence intervals that encapsulate most of the experimental data. Results indicate that specimens loaded perpendicular to the build direction (H-direction) exhibit superior fatigue resistance compared to those loaded parallel to it (S-direction). Quantitative validation identifies the Smith-Watson-Topper model and the Morrow model as the optimal predictors for the two directions. This work provides a reliable tool for fatigue assessment under data-scarce conditions.

由于数据有限和材料分散严重，增材制造铝合金的疲劳寿命预测具有挑战性。为了解决这个问题，本研究提出了一个用于概率预测和模型选择的贝叶斯不确定性量化框架。对激光粉末床熔合（LPBF） AlSi10Mg试样在两种构建方向下进行了疲劳试验。采用贝叶斯推理更新四个候选模型的参数，以预测不确定性的形式表征数据稀缺性。然后使用u池和模型证据度量来定量评估模型性能。提出的框架有效地生成了95%的置信区间，封装了大多数实验数据。结果表明，竖向加载（h方向）比平行加载（s方向）具有更好的抗疲劳性能。定量验证表明Smith-Watson-Topper模型和Morrow模型是两个方向的最佳预测因子。这项工作为数据稀缺条件下的疲劳评估提供了可靠的工具。

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引用次数: 0

Vision-driven and Bayesian-enhanced YOLO-PINN hybrid framework for crack propagation and fatigue life prediction 视觉驱动和贝叶斯增强的ylo - pinn混合框架用于裂纹扩展和疲劳寿命预测

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-22 DOI: 10.1016/j.ijfatigue.2026.109511

Zhizhuo Zhang , Mengchuang Zhang , Yan Li , Enrico Zappino , Zhiping Yin

Accurate detection and prediction of crack propagation are critical for maintaining the integrity and extending the service life of aerospace structures. We present a novel hybrid framework that integrates deep learning-based computer vision with physics-informed modeling to improve crack-growth forecasting. First, an enhanced You Only Look Once (YOLO) object-detection and segmentation network precisely extracts crack morphology from inspection images. These measurements feed into physics-informed neural network (PINN) that embeds the governing fracture mechanics equations to predict temporal growth trajectories. To maximize predictive accuracy, a Bayesian correlation scheme iteratively selects and refines the training set, ensuring inclusion of the most informative imaging samples. This feedback loop continuously enhances the model’s adaptability and reliability. Validation on benchmark datasets demonstrates that our hybrid approach significantly outperforms purely data-driven or purely physics-based methods, offering robust, real-time structural health monitoring. The proposed methodology provides a novel approach for predictive maintenance and lifecycle management of critical aerospace components.

裂纹扩展的准确检测和预测对于保持航天结构的完整性和延长其使用寿命至关重要。我们提出了一种新的混合框架，将基于深度学习的计算机视觉与物理信息建模相结合，以改进裂缝增长预测。首先，一个增强的You Only Look Once （YOLO）目标检测和分割网络精确地从检测图像中提取裂纹形态。这些测量结果输入到物理信息神经网络（PINN）中，该网络嵌入了控制断裂力学方程，以预测时间生长轨迹。为了最大限度地提高预测精度，贝叶斯相关方案迭代地选择和改进训练集，确保包含最具信息量的成像样本。这种反馈回路不断增强了模型的适应性和可靠性。在基准数据集上的验证表明，我们的混合方法明显优于纯粹的数据驱动或纯粹基于物理的方法，提供强大的实时结构健康监测。该方法为航空航天关键部件的预测性维护和生命周期管理提供了一种新的方法。

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引用次数: 0