International Journal of Fatigue最新文献

Fatal defect determination and nanotwin-assisted early damage in ultra-high cycle fatigue of additively manufactured titanium alloy 增材制造钛合金超高周疲劳致命缺陷确定及纳米孪晶辅助早期损伤

IF 6 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-14 DOI: 10.1016/j.ijfatigue.2026.109491

MingHui Dai, Kun Yang, Xue Li, YaoHan Du, HaiTao Zhu, HongPing Zhang, JingJiang Wei, ChengLai Xin, QingYuan Wang

引用次数: 0

Multicondition fatigue behaviors of GH4169 alloy film cooling holes under thermo-mechanical coupling effects 热-力耦合作用下GH4169合金薄膜冷却孔的多工况疲劳行为

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-14 DOI: 10.1016/j.ijfatigue.2026.109492

Longqing Lei , Zhengqiu Zhang , Weibing Liu , Yuefei Luo , Wei Chen , Yangjie Zuo

The fatigue behavior of film cooling hole structures in hot-section components, particularly under thermo-mechanical coupling effects, is crucial for enhancing the durability and performance of gas turbines. This study investigates the fatigue performance of four typical film-cooling hole configurations (30° and 45° cylindrical holes (CH-30° and CH-45°), fan-shaped holes (FSH), and laidback fan-shaped holes (LFSH)) fabricated from the GH4169 alloy. A combined experimental and numerical approach was employed, examining the fatigue life and crack propagation under three temperature conditions: 25 °C, 500 °C, and 500 °C with coolant pass through the hole, which simulated the film cooling. The results demonstrate that fatigue life is significantly influenced by the geometry of the cooling holes and thermal environment. CH-30° consistently exhibited superior fatigue resistance across all temperature conditions. At 500 °C, the introduction of coolant notably improved fatigue life, especially for configurations such as LFSH, which showed an enhanced fatigue life compared to conventional shapes. The study also reveals that crack initiation and propagation predominantly occur at the upstream edge of the film holes, with significant variations in crack evolution mechanisms observed across different hole types and thermal conditions. This research provides a comprehensive understanding of the fatigue behavior of film-cooling hole structures with different thermal conditions and offers valuable insights into the optimization of hole geometries for improved fatigue resistance in high-temperature applications.

热截面部件的气膜冷却孔结构的疲劳性能，特别是在热-力耦合作用下的疲劳性能，对提高燃气轮机的耐久性和性能至关重要。研究了GH4169合金四种典型的气膜冷却孔结构（30°和45°圆柱孔（CH-30°和CH-45°）、扇形孔（FSH）和懒散扇形孔（LFSH））的疲劳性能。采用实验与数值相结合的方法，在25°C、500°C和500°C三种温度条件下，研究了冷却剂通过孔的疲劳寿命和裂纹扩展，模拟了膜状冷却。结果表明，冷却孔的几何形状和热环境对疲劳寿命有显著影响。CH-30°在所有温度条件下均表现出优异的抗疲劳性能。在500°C时，冷却剂的引入显著提高了疲劳寿命，特别是对于LFSH这样的配置，与传统形状相比，它的疲劳寿命得到了提高。研究还表明，裂纹的起裂和扩展主要发生在膜孔的上游边缘，不同孔类型和热条件下裂纹的演化机制存在显著差异。该研究提供了对不同热条件下气膜冷却孔结构疲劳行为的全面理解，并为优化孔几何形状以提高高温应用中的抗疲劳性提供了有价值的见解。

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引用次数: 0

From stress field to multiaxial fatigue life: A novel physics-guided neural network framework accounting for stress ratio, phase angle, and biaxiality ratio 从应力场到多轴疲劳寿命：一种新的物理导向神经网络框架，用于计算应力比、相位角和双轴比

IF 6 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-13 DOI: 10.1016/j.ijfatigue.2026.109497

Amir Mohammad Mirzaei

引用次数: 0

Microstructural evolution for enhanced high temperature fretting fatigue resistance in GH4169 via laser assisted ultrasonic surface rolling process 激光辅助超声表面轧制增强GH4169耐高温微动疲劳性能的组织演变

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-12 DOI: 10.1016/j.ijfatigue.2026.109487

Hao Zhang , Daoxin Liu , Jing Yang , Mengyao Li , Junnan Wu , Yueyang Li , Yanjie Liu , Yu Zhang , Xiaohua Zhang , Chang Ye

Laser assisted ultrasonic surface rolling process (LA-USRP) was applied to GH4169 superalloy to improve its high temperature fretting fatigue resistance. Conventional USRP increased the fretting fatigue life under axial tension–tension cyclic loading (stress ratio R = 0.1, frequency of 131 ± 2 Hz, maximum stress of 800 MPa, and contact pressure of 85 MPa) at 600 °C by a factor of 3.3, whereas LA-USRP achieved a 14.7-fold enhancement compared to the base material. This superior performance is primarily attributed to advantageous microstructural evolution, including a thicker gradient nanostructured surface layer (average surface grain size around 25 nm), higher compressive residual stresses (surface −2079 MPa, maximum −2443 MPa at around 35 μm depth), and the formation of refined nanotwins and stabilized 9R phase. These features significantly improve cyclic stability of compressive residual stresses (relaxation reduced from 89.6 % in USRP to 35.9 % in LA-USRP after fatigue) and impede dislocation motion at elevated temperatures. These findings offer a promising approach for enhancing the high temperature fretting fatigue performance of critical aero-engine components.

为提高GH4169高温合金的耐高温微动疲劳性能，采用激光辅助超声表面轧制工艺（LA-USRP）对其进行了加工。传统USRP在600 °C时，将轴向拉伸-拉伸循环加载（应力比R = 0.1，频率为131 ± 2 Hz，最大应力为800 MPa，接触压力为85 MPa）下的微动疲劳寿命提高了3.3倍，而LA-USRP则比基材提高了14.7倍。这种优异的性能主要归功于有利的微观结构演变，包括更厚的梯度纳米结构表面层（平均表面晶粒尺寸约为25 nm），更高的压缩残余应力（表面- 2079 MPa，深度约为35 μm时最大- 2443 MPa），以及精炼纳米孪晶和稳定9R相的形成。这些特征显著提高了压缩残余应力的循环稳定性（疲劳后松弛从USRP的89.6% %降低到LA-USRP的35.9% %），并阻碍了位错在高温下的运动。这些发现为提高航空发动机关键部件的高温微动疲劳性能提供了一条有希望的途径。

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引用次数: 0

Data-driven fatigue life prediction of corroded steel wires: A transfer learning on stacking interpretable model and feature sensitivity analysis 数据驱动的锈蚀钢丝疲劳寿命预测：基于叠加可解释模型和特征敏感性分析的迁移学习

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-12 DOI: 10.1016/j.ijfatigue.2026.109498

Tao Huang , Chunfeng Wan , Tingbin Liu , Yucheng Zhang , Xiangtao Lu , Youliang Ding , Hanwei Zhao , Changqing Miao , Songtao Xue

The study of the fatigue performance of corroded steel wires in bridge cables holds significant scientific value for advancing structural theory and informing engineering practice. To address key challenges in fatigue life prediction such as the scarcity of the complexity of nonlinear relationships and the lack of model interpretability, this study proposes a progressive solution framework consisting of integrated optimization, transfer validation, model interpretation, platform development. A dual-source heterogeneous database (A/B) was first constructed by integrating 422 sets of specimens data from the literature with 30 sets of experimental data obtained through independently conducted corrosion tests. An integration strategy based on stacked-transfer models is used to couple the strengths of six different machine learning (ML) models. The improved sparrow optimisation (ISSA) algorithm was employed for hyperparameter optimization. The results demonstrate that the proposed Stacking model surpasses both individual base learners and existing mathematical models from literature and specifications in prediction accuracy. When transferred to new independent datasets, the model maintains excellent predictive performance, validating its strong generalization capability. Furthermore, by incorporating the SHAP framework, the study systematically deciphers the model’s decision-making mechanism and quantifies the contribution distribution of individual parameters to fatigue life. Finally, to enhance model applicability, a web-based human–computer interaction platform for intelligent fatigue life prediction was developed based on the stacking-SHAP model. This study provides a data-algorithm-platform trinity solution for the whole life cycle management of bridge cables.

研究桥梁缆索腐蚀钢丝的疲劳性能，对于推进结构理论和指导工程实践具有重要的科学价值。针对疲劳寿命预测中非线性关系复杂性不足和模型可解释性不足等关键问题，本文提出了一个由集成优化、传递验证、模型解释和平台开发组成的渐进式解决方案框架。首先将文献中422组试样数据与独立进行腐蚀试验获得的30组实验数据进行整合，构建双源异构数据库（A/B）。采用基于堆叠迁移模型的集成策略，对六种不同机器学习模型的优势进行了耦合。采用改进的麻雀优化算法（ISSA）进行超参数优化。结果表明，本文提出的叠加模型在预测精度上优于单个基础学习器和现有文献和规范的数学模型。当转移到新的独立数据集时，该模型保持了良好的预测性能，验证了其强大的泛化能力。结合SHAP框架，系统解读了模型的决策机制，量化了各参数对疲劳寿命的贡献分布。最后，为了提高模型的适用性，开发了基于web的基于堆叠- shap模型的智能疲劳寿命预测人机交互平台。本研究为桥梁电缆全生命周期管理提供了数据-算法-平台三位一体的解决方案。

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引用次数: 0

Competing role of volumetric defects and microstructure on the fatigue behavior of additively manufactured Inconel 718: An experimental study 体积缺陷和微观组织对增材制造Inconel 718疲劳性能影响的实验研究

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-10 DOI: 10.1016/j.ijfatigue.2026.109486

Indrajit Nandi , Sajith Soman , Reza Molaei , Will Tilson , Nima Shamsaei , Shuai Shao

This study investigates the competing role of volumetric defects and microstructure on the fatigue behavior of additively manufactured Inconel 718 (IN718), with emphasis on the crack initiation mechanism. IN718 rods were fabricated using laser powder bed fusion with tuned process parameters and heat treatments to obtain diverse defect contents and microstructures. Both uniaxial tensile and fully-reversed, force-controlled fatigue tests were performed, and fractography was conducted to analyze various features observed at fatigue crack initiation sites. The influence of defects and microstructure was more pronounced on fatigue behavior than on tensile behavior. Both microstructure- and defect-mediated fatigue crack initiations were observed. For the former, facets were observed at the crack initiation sites which were due to the formation and operation of persistent slip bands. Interestingly, results revealed a similar dependence of fatigue life on the feature size at the crack initiation sites, regardless of the crack initiation mechanism.

本文研究了体积缺陷和微观组织对增材制造IN718疲劳性能的影响，重点研究了裂纹的起裂机理。通过调整工艺参数和热处理，采用激光粉末床熔合法制备了不同缺陷含量和显微组织的IN718棒。进行了单轴拉伸和完全反向力控制疲劳试验，并进行了断口分析，分析了疲劳裂纹萌生部位的各种特征。缺陷和显微组织对疲劳性能的影响大于对拉伸性能的影响。观察到微观组织和缺陷介导的疲劳裂纹萌生。对于前者，在裂纹起裂部位观察到由于持续滑移带的形成和作用而产生的切面。有趣的是，结果显示，无论裂纹起裂机制如何，疲劳寿命与裂纹起裂部位的特征尺寸有相似的依赖关系。

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引用次数: 0

Fatigue mechanisms and life prediction of cracked steel elements repaired with cold-expanded crack-stop holes 冷扩止裂孔修复裂纹钢构件的疲劳机理及寿命预测

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-10 DOI: 10.1016/j.ijfatigue.2026.109484

Lu Ke , Youlin Li , Chuanxi Li , Xu Jiang , Jun Ye , Ailong Chen , Guojin Li

Fatigue cracks in steel elements repaired with traditional crack-stop holes are susceptible to perforation, enabling propagation and resulting in inadequate fatigue life improvement. The fatigue performance of cracked steel elements repaired by cold-expanded crack-stop holes was experimentally investigated, and the effects of cold expansion ratios and hole-to-crack tip distances on the fatigue life were examined. Finite element (FE) simulation tests were conducted to reveal the residual stress distributions around the crack-stop holes after cold expansion. The results show that higher cold expansion ratios significantly enhance fatigue life under an identical hole-to-crack tip distance. When the hole-to-crack tip distance was 0 mm, a cold expansion ratio of 2% yielded the greatest fatigue life improvement, with a 50.82% increase compared to specimens without cold expansion. Moreover, the residual stress was distributed nonlinearly along the thickness direction of the steel elements, with the peak residual stress occurring near the exit side of the cold expansion mandrel. Finally, based on the critical distance theory and residual stress weight allocation coefficient, a fatigue life prediction model for the crack initiation at the hole edges was developed. Simultaneously, based on linear elastic fracture mechanics, a fatigue life prediction model for the crack growth was proposed. The results indicated that the experimental and predicted values of the total fatigue life are in good agreement. This study offers a cold expansion technique for crack-stop holes, providing a novel technique for extending the fatigue life of cracked steel structures.

传统止裂孔修复钢构件疲劳裂纹容易穿孔，容易扩展，导致疲劳寿命提高不足。试验研究了冷扩止裂孔修复裂纹钢构件的疲劳性能，考察了冷扩比和孔-裂纹尖端距离对疲劳寿命的影响。通过有限元模拟试验，揭示了冷胀后止裂孔周围的残余应力分布。结果表明，在相同的孔-裂纹尖端距离下，较高的冷膨胀率显著提高了疲劳寿命。当孔-裂纹尖端距离为0 mm时，冷膨胀率为2%的试样疲劳寿命提高幅度最大，比未冷膨胀的试样疲劳寿命提高50.82% %。残余应力沿钢件厚度方向呈非线性分布，残余应力峰值出现在冷胀芯筒出口侧附近。最后，基于临界距离理论和残余应力权重分配系数，建立了孔边缘裂纹起裂疲劳寿命预测模型。同时，基于线弹性断裂力学，提出了裂纹扩展的疲劳寿命预测模型。结果表明，总疲劳寿命的实验值与预测值吻合较好。本研究提出了一种止裂孔的冷扩技术，为延长裂纹钢结构的疲劳寿命提供了一种新技术。

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引用次数: 0

Fully-lamellar equiaxed structure mediated excellent high-temperature fatigue crack growth resistance of Ti-48Al-2Cr-2Nb alloy fabricated via twin-wire directed energy deposition-arc process 双线定向能沉积-电弧工艺制备的Ti-48Al-2Cr-2Nb合金具有优异的耐高温疲劳裂纹扩展性能

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-09 DOI: 10.1016/j.ijfatigue.2026.109488

Danqi Zhang , Chen Shen , Lin Wang , Wenlu Zhou , Ting Zhang , Ying Li , Yuelong Zhang , Fang Li , Jianwen Xin , Kanglong Wu , Gang Ruan , Xueming Hua

As a critical milestone of twin-wire directed energy deposition-arc (TW-DED-arc) technology, we present the first report on the excellent fatigue crack growth (FCG) performance of a Ti–48Al–2Cr–2Nb (TiAl-4822) alloy with a refined fully-lamellar microstructure. FCG tests conducted on standard compact tension specimens from two orthogonal directions under cyclic loading at 650 °C (R = 0.1) demonstrated a high fatigue threshold (∼8.0 MPa·m^1/2) and low crack propagation rates compared to conventionally manufactured counterparts. The isotropic microstructure rendered crack resistance insensitive to deposition direction. In-situ tensile analysis under electron back scattered diffraction revealed that the enhanced performance originates from refined lamellar spacing, which promoted super-dislocation (SD) activity. Tortuous crack paths formed by mortise–tenon interlocks in inter-lamellar crack and zigzag trans-lamellar cracking, which effectively deflected cracks and dissipate energy. Furthermore, high volume fraction of γ-phase (89.4%) with low stacking fault energy facilitated dislocation dissociation and deformation twinning (DT). These mechanisms collectively enhanced stress relaxation through twin interactions and SD immobilization, significantly improving crack resistance. This study not only reports a previously undocumented property profile but also underscores the technological potential of TW-DED-arc for manufacturing high-performance titanium aluminide components.

作为双线定向能沉积电弧（tw - ed -arc）技术的一个重要里程碑，我们首次报道了一种具有精致的全层状组织的Ti-48Al-2Cr-2Nb （TiAl-4822）合金的优异疲劳裂纹扩展（FCG）性能。在650°C （R = 0.1）循环加载下，对两个正交方向的标准致密拉伸试样进行的FCG试验表明，与常规制造的试件相比，其疲劳阈值高（~ 8.0 MPa·m1/2），裂纹扩展率低。各向同性组织使得抗裂性能对沉积方向不敏感。电子背散射衍射原位拉伸分析表明，晶片间距的细化促进了超位错（SD）活性的提高。片间裂纹和片间裂纹中榫卯互锁形成的弯曲裂纹路径，有效地偏转了裂纹并耗散了能量。高体积分数γ-相（89.4%）和低层错能有利于位错解离和变形孪晶（DT）。这些机制通过孪生相互作用和SD固定共同增强应力松弛，显著提高抗裂性。这项研究不仅报告了以前未记载的性能概况，而且强调了tw - ed电弧在制造高性能钛铝组件方面的技术潜力。

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引用次数: 0

Investigating the influence of thermal Post-Processing on the Mode I and Mode II fatigue fracture resistance of additively manufactured carbon Fiber composites 研究了热后处理对增材制造碳纤维复合材料I型和II型疲劳断裂抗力的影响

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-08 DOI: 10.1016/j.ijfatigue.2026.109485

Zane Forbes , Xiaobo Yu , Garth Pearce , Mathew W Joosten

Interlaminar defects such as voids and incomplete fibre–matrix consolidation limit the fatigue performance of additively manufactured (AM) continuous-fibre composites. This study examines how thermal post-processing influences Mode I (DCB) and Mode II (ENF) fatigue crack-growth behaviour in 3D-printed CF/PA laminates. Across all load levels, post-processed specimens showed substantially improved fatigue resistance, requiring approximately 40–50% higher energy-release rates to reach the same crack-growth rates as the as-printed material. Crack-length–versus-cycle curves further demonstrated that post-processed specimens endured significantly more cycles to reach equivalent crack lengths. Microscopy revealed distinct mechanisms underlying these improvements: void elimination and smoother crack planes in Mode I, and increased crack-face contact and frictional dissipation along shear-sliding surfaces in Mode II. Finite-element simulations using the CF20 fatigue cohesive model reproduced the experimental trends with minimal calibration. Overall, thermal post-processing provides a simple and effective pathway to enhance the fatigue durability of additively manufactured composite laminates.

层间缺陷如空洞和纤维基体固结不完全等限制了增材制造（AM）连续纤维复合材料的疲劳性能。本研究探讨了热后处理如何影响3d打印CF/PA层压板的I型（DCB）和II型（ENF）疲劳裂纹扩展行为。在所有荷载水平下，后处理的试样显示出显著提高的抗疲劳性，需要大约40-50%的能量释放率才能达到与打印材料相同的裂纹扩展率。裂纹长度与循环曲线进一步表明，经过后处理的试样承受了更多的循环来达到等效的裂纹长度。显微镜显示了这些改进背后的不同机制：在模式I中，空洞消除和更光滑的裂纹面，在模式II中，裂纹面接触和沿剪切滑动表面的摩擦耗散增加。使用CF20疲劳内聚模型的有限元模拟以最小的校准再现了实验趋势。综上所述，热后处理为提高增材复合材料层合板的疲劳耐久性提供了一条简单有效的途径。

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引用次数: 0

Data driven topology optimization of AM parts accounting for process-affected fatigue performance: Application to automotive and aerospace components 考虑工艺影响疲劳性能的增材制造零件的数据驱动拓扑优化：在汽车和航空航天部件上的应用

IF 6.8 2区材料科学 Q1 ENGINEERING, MECHANICAL

International Journal of Fatigue

Pub Date : 2026-01-07 DOI: 10.1016/j.ijfatigue.2026.109481

Alessio Centola , Alberto Ciampaglia , Carlo Boursier Niutta , Filippo Berto , Davide Salvatore Paolino , Andrea Tridello

The present paper presents two novel data-driven topology optimization (TO) procedures to design lighter additively manufactured (AM) fatigue resistant components. The first TO method is driven by a probabilistic machine learning (ML) algorithm based on a Bayesian Neural Network (BNN), trained on fatigue data from the literature to assess probabilistic stress-life (PSN) curves. These curves are used to predict the allowable design stress for TO and are predicted directly from AM process parameters, the risk volume, and thermal and surface treatments. The second TO design procedure is instead driven by another BNN, trained to predict the maximum critical defect size from the process parameters. The TO limit stress is computed from the predicted critical defect and the threshold stress intensity factor K_th. After the TO, the critical stress intensity factor K_I in the component is computed and compared against K_th, to assess the effectiveness of this design procedure. These two frameworks are applied to the design of an SS316L automotive suspension lower control arm and a Ti6Al4V aerospace bracket, respectively. With the following framework, the limit stress calculation does not require specifically designed experimental campaigns and prototyping, as previously sparse experimental knowledge can be embedded in a powerful design tool, which allows for preventing fatigue failures, while accounting directly for the influence of the AM process parameters.

本文提出了两种新的数据驱动拓扑优化（TO）方法来设计更轻的增材制造（AM）抗疲劳部件。第一种TO方法由基于贝叶斯神经网络（BNN）的概率机器学习（ML）算法驱动，该算法根据文献中的疲劳数据进行训练，以评估概率应力寿命（PSN）曲线。这些曲线用于预测to的允许设计应力，并直接从增材制造工艺参数、风险体积、热处理和表面处理中进行预测。第二个TO设计程序由另一个BNN驱动，该BNN经过训练，可以从工艺参数中预测最大临界缺陷尺寸。根据预测的临界缺陷和阈值应力强度因子Kth计算极限应力。在TO之后，计算组件中的临界应力强度因子KI并与Kth进行比较，以评估该设计过程的有效性。这两种框架分别应用于SS316L汽车悬架下控制臂和Ti6Al4V航空航天支架的设计。有了下面的框架，极限应力计算不需要专门设计的实验活动和原型，因为以前稀疏的实验知识可以嵌入到一个强大的设计工具中，这可以防止疲劳失效，同时直接考虑到增材制造工艺参数的影响。

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引用次数: 0