International Journal of Fatigue最新文献_第6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 6.8 2区材料科学

International Journal of Fatigue Pub Date : 2026-06-01 Epub Date: 2026-01-30 DOI: 10.1016/j.ijfatigue.2026.109523

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

{"title":"Enhancing fatigue life of L12-strengthened multi-principal element alloy by tailoring grain boundary characteristics and precipitation","authors":"Shaoxin Cai , Jingping Cui , Baijun Yang , Dong Han , Jianqiang Wang","doi":"10.1016/j.ijfatigue.2026.109523","DOIUrl":"10.1016/j.ijfatigue.2026.109523","url":null,"abstract":"<div><div>A significant challenge has recently been highlighted in L1<sub>2</sub>-strengthened multi-principal element alloys (MPEAs), where the Al-Ti-bearing systems are prone to forming the coarse-sized discontinuous precipitates (DPs) along grain boundaries (GBs) during aging. This intensifies the strain localization near GBs, thus posing a potential threat to the fatigue performance of the alloy, as reported in traditional alloys. To address this, the grain boundary engineering (GBE) strategy was applied to a (NiCoCr)<sub>94</sub>Al<sub>3</sub>Ti<sub>3</sub> MPEA through simple thermomechanical treatment, and its influence on DPs and the resulting tension–tension fatigue behavior was systematically examined. The results reveal that GBE treatment can significantly increase the fraction of special boundaries dominated by Σ3 boundaries and disrupt the connectivity of random high-angle grain boundaries, thereby effectively inhibiting the formation of DPs. Such a microstructure optimization leads to a 2–4 times improvement in the fatigue life, depending on the stress amplitudes. The enhanced properties are attributed to the synergistic role of modified GB characteristics and DP suppression. This effect promotes the deformation uniformity and alleviates the strain incompatibility between the two sides of boundaries, thus enhancing crack initiation and propagation resistance. Our work provides a simple yet effective pathway for improving the fatigue performance of L1<sub>2</sub>-strengthened MPEAs, particularly under high-stress amplitudes where GB cracking is the dominant failure mode.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109523"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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

International Journal of Fatigue Pub Date : 2026-06-01 Epub Date: 2026-01-25 DOI: 10.1016/j.ijfatigue.2026.109521

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

{"title":"An energy-based physics–data fusion model for thermomechanical fatigue life prediction of directionally solidified superalloys","authors":"Jundong Wang , Yuanmin Tu , Song Wu , Pengfei He , Zhixun Wen","doi":"10.1016/j.ijfatigue.2026.109521","DOIUrl":"10.1016/j.ijfatigue.2026.109521","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109521"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146048294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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

International Journal of Fatigue Pub Date : 2026-06-01 Epub 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

{"title":"Data-driven fatigue life prediction of corroded steel wires: A transfer learning on stacking interpretable model and feature sensitivity analysis","authors":"Tao Huang , Chunfeng Wan , Tingbin Liu , Yucheng Zhang , Xiangtao Lu , Youliang Ding , Hanwei Zhao , Changqing Miao , Songtao Xue","doi":"10.1016/j.ijfatigue.2026.109498","DOIUrl":"10.1016/j.ijfatigue.2026.109498","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109498"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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

International Journal of Fatigue Pub Date : 2026-06-01 Epub 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

{"title":"Microstructural evolution for enhanced high temperature fretting fatigue resistance in GH4169 via laser assisted ultrasonic surface rolling process","authors":"Hao Zhang , Daoxin Liu , Jing Yang , Mengyao Li , Junnan Wu , Yueyang Li , Yanjie Liu , Yu Zhang , Xiaohua Zhang , Chang Ye","doi":"10.1016/j.ijfatigue.2026.109487","DOIUrl":"10.1016/j.ijfatigue.2026.109487","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109487"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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 6.8 2区材料科学

International Journal of Fatigue Pub Date : 2026-06-01 Epub 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

{"title":"The effects of austempering time on mechanical properties of the novel GCr15Si1MoNbV bearing steel and on its rolling contact fatigue behaviors","authors":"Yanhui Wang , Ziqi Liu , Xubiao Wang , Xiang Chen , Xiliang Zhang , Wenfei Shen , Qian Yang , Leijie Zhao , Zhinan Yang","doi":"10.1016/j.ijfatigue.2026.109519","DOIUrl":"10.1016/j.ijfatigue.2026.109519","url":null,"abstract":"<div><div>Rolling contact fatigue (RCF) is a critical failure mode of bearings. In this study, the novel GCr15Si1MoNbV bearing steel was subjected to low-temperature salt-bath austempering, and the effects of phase transformation during austempering on microstructure, mechanical properties and RCF behavior were investigated experimentally using scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), and RCF testing. The specimen austempered at 190 °C for 10 h with a multiphase microstructure composed of nanobainite, martensite, and a high volume fraction of retained austenite exhibited exceptional performance. This kind of multiphase microstructure provided high surface hardness, excellent impact toughness, and a favorable residual stress gradient characterized by compressive stress at surface and tensile stress at subsurface, which collectively delayed crack initiation and propagation. As a result, the basic rating life (<em>L<sub>10</sub></em>), the median life (<em>L<sub>50</sub>)</em>, and the characteristic life (<em>V<sub>s</sub></em>) of the martensite–nanobainite–austenite 10 h specimen were 2–3 times to those of the martensite-dominated 2 h specimen, and 3–5 times to those of the nanobainite-dominated 48 h specimen. These findings indicate that the synergistic optimization of multiphase microstructure and residual stress gradient is the key mechanism for enhancing the RCF performance of bearing steels.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109519"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146072457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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

International Journal of Fatigue Pub Date : 2026-06-01 Epub 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

{"title":"Redefining stress triaxiality for ultra-low cycle fatigue of structural steels","authors":"Qun He , Michael C.H. Yam , Xue-Mei Lin , H.C. Ho , Kwok-Fai Chung","doi":"10.1016/j.ijfatigue.2026.109520","DOIUrl":"10.1016/j.ijfatigue.2026.109520","url":null,"abstract":"<div><div>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 <span><math><msub><mi>J</mi><mn>2</mn></msub></math></span> 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., <span><math><msub><mi>J</mi><mn>2</mn></msub></math></span>, 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.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109520"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146048295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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

International Journal of Fatigue Pub Date : 2026-06-01 Epub 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

{"title":"Fatigue mechanisms and life prediction of cracked steel elements repaired with cold-expanded crack-stop holes","authors":"Lu Ke , Youlin Li , Chuanxi Li , Xu Jiang , Jun Ye , Ailong Chen , Guojin Li","doi":"10.1016/j.ijfatigue.2026.109484","DOIUrl":"10.1016/j.ijfatigue.2026.109484","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109484"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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

International Journal of Fatigue Pub Date : 2026-06-01 Epub Date: 2026-01-08 DOI: 10.1016/j.ijfatigue.2026.109485

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

{"title":"Investigating the influence of thermal Post-Processing on the Mode I and Mode II fatigue fracture resistance of additively manufactured carbon Fiber composites","authors":"Zane Forbes , Xiaobo Yu , Garth Pearce , Mathew W Joosten","doi":"10.1016/j.ijfatigue.2026.109485","DOIUrl":"10.1016/j.ijfatigue.2026.109485","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109485"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145956832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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

International Journal of Fatigue Pub Date : 2026-06-01 Epub Date: 2026-01-14 DOI: 10.1016/j.ijfatigue.2026.109492

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

{"title":"Multicondition fatigue behaviors of GH4169 alloy film cooling holes under thermo-mechanical coupling effects","authors":"Longqing Lei , Zhengqiu Zhang , Weibing Liu , Yuefei Luo , Wei Chen , Yangjie Zuo","doi":"10.1016/j.ijfatigue.2026.109492","DOIUrl":"10.1016/j.ijfatigue.2026.109492","url":null,"abstract":"<div><div>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.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109492"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145976043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mechanistic insight and universal life prediction of strain rate-dependent fatigue in nickel-based superalloy at elevated temperature 镍基高温合金高温应变速率相关疲劳的机理及通用寿命预测

IF 6.8 2区材料科学

International Journal of Fatigue Pub Date : 2026-06-01 Epub Date: 2026-01-21 DOI: 10.1016/j.ijfatigue.2026.109512

Hao-Qi Fan , Kai-Shang Li , Ning Yao , Wen-Rui Nie , Run-Zi Wang , Ti-Wen Lu , Lu Cheng , Xiu-Fang Gong , Xian-Cheng Zhang , Shan-Tung Tu

{"title":"Mechanistic insight and universal life prediction of strain rate-dependent fatigue in nickel-based superalloy at elevated temperature","authors":"Hao-Qi Fan , Kai-Shang Li , Ning Yao , Wen-Rui Nie , Run-Zi Wang , Ti-Wen Lu , Lu Cheng , Xiu-Fang Gong , Xian-Cheng Zhang , Shan-Tung Tu","doi":"10.1016/j.ijfatigue.2026.109512","DOIUrl":"10.1016/j.ijfatigue.2026.109512","url":null,"abstract":"<div><div>Start-up and shut-down transients in turbomachinery impose varying strain rates that affect the in-service life of high-temperature components. However, the quantitative role of strain rate sensitivity in high-temperature fatigue of nickel-based superalloys remains inadequately reflected in damage mechanism and life prediction. In this study, fully-reversed strain-controlled low cycle fatigue (LCF) tests were performed at 650 ℃ over a wide range of strain rates from 5 × 10<sup>−5</sup> to 1 × 10<sup>−2</sup> s<sup>−1</sup>. The experimental results reveal the existence of a threshold strain-rate range for nickel-based superalloy IN718. When the strain rate exceeds this threshold, the fatigue life remains nearly constant with increasing strain rate. The cracking behavior is dominated by the transgranular-intergranular mixed mode. In contrast, at strain rates below this threshold, the fatigue life decreases rapidly due to the time available for oxidation- and creep-assisted damage. Based on these observations, a modified energy-based model incorporating the strain rate sensitivity was proposed using tensile-derived plastic strain energy density, achieving a prediction accuracy of 97% within a ±2 error band. These findings provide an effective strategy for enhancing the service reliability of high-temperature rotating components.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"207 ","pages":"Article 109512"},"PeriodicalIF":6.8,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146033266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0