Wandong Wang , Hongchen Zhao , Zhinan Zhang , Wenbo Sun , Calvin Rans , Yu’e Ma
{"title":"An improved understanding of fatigue crack growth behavior of multiple collinear cracks in hybrid composite structures","authors":"Wandong Wang , Hongchen Zhao , Zhinan Zhang , Wenbo Sun , Calvin Rans , Yu’e Ma","doi":"10.1016/j.ijfatigue.2025.108997","DOIUrl":"10.1016/j.ijfatigue.2025.108997","url":null,"abstract":"<div><div>Accurately predicting MSD crack growth behavior in hybrid metal–composite structures is challenging due to the complex interactions of fiber bridging and delamination failure in fiber–metal laminates (FMLs). These mechanisms enhance damage tolerance but complicate crack analysis. This paper proposes two analytical models to address crack growth in FMLs with multiple collinear cracks. The first model analyzes crack openings and stress intensity factors (SIFs) for multiple cracks, capturing the physics of MSD cracking, but it is cumbersome to implement. The second model simplifies the problem by considering energy dissipation, treating the MSD scenario as a single crack in a finite plate and equating the energy dissipation between both cases. Both models were validated and show accurate predictions of crack growth behavior, capturing crack acceleration effectively. The results emphasize the importance of accounting for the contributions of bridging and stiffening mechanisms in FMLs, particularly load redistribution, which influences crack growth.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 108997"},"PeriodicalIF":5.7,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143883002","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}
Yunong Zhai , Hao Qu , Dongsheng Li , Ende Ge , Ruiheng Xiao , Jian Yang
{"title":"Effect of bolt preload uncertainty on fatigue reliability of single-lap, countersunk composite bolted joints considering forced assembly interaction","authors":"Yunong Zhai , Hao Qu , Dongsheng Li , Ende Ge , Ruiheng Xiao , Jian Yang","doi":"10.1016/j.ijfatigue.2025.109017","DOIUrl":"10.1016/j.ijfatigue.2025.109017","url":null,"abstract":"<div><div>Bolt preload plays a crucial part in ensuring the security of composite bolted joints. The actual bolt preload level displays noticeable fluctuation during aircraft assembly, impacting the fatigue reliability of joints. Assembly gaps commonly arise at the mating surface of composite airframes, and forced assembly is a prevalent method for closing the gaps before applying bolt preload, which leads to the bolt head fatigue cracking, weakening the fatigue performance of joints. In this study, the effect of bolt preload uncertainty on fatigue reliability of single-lap, countersunk composite bolted joints considering forced assembly interaction was systematically evaluated. The combination of progressive fatigue damage model (PFDE) and extended finite element method (XFEM) was developed to characterize the hole bearing damage and the bolt head fatigue cracking respectively. The findings show that the joints with forced assembly present a shorter fatigue life with increasing bolt preload under the fatigue load level of 70% <span><math><mrow><msubsup><mi>F</mi><mrow><mi>x</mi></mrow><mrow><mi>bro</mi></mrow></msubsup><mrow><mo>(</mo><mn>2</mn><mo>%</mo><mo>)</mo></mrow></mrow></math></span> due to bolt head fatigue cracking. Higher bolt preload makes the bolt head fatigue cracking occur earlier, thus stiffness degrades and fatigue failure more rapidly. The bolt head crack size shows a growing trend with increased bolt preload, leading to a lower residual strength of joints. With a Gaussian distribution of actual bolt preload, the composite bolted joints after forced assembly presents a right-skewed distribution fatigue life under the fatigue load level of 70% <span><math><mrow><msubsup><mi>F</mi><mrow><mi>x</mi></mrow><mrow><mi>bro</mi></mrow></msubsup><mrow><mo>(</mo><mn>2</mn><mo>%</mo><mo>)</mo></mrow></mrow></math></span>, since the bolt head fatigue cracking would be triggered at a bolt preload lower than the mean value.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109017"},"PeriodicalIF":5.7,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143869039","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}
R.Q. Cao , Y.L. Lu , F.X. Meng , J. Pan , Q. Yu , Y. Li
{"title":"Enhanced high-cycle fatigue behavior of electrodeposited nickel plates with optimized grain-size gradient structures","authors":"R.Q. Cao , Y.L. Lu , F.X. Meng , J. Pan , Q. Yu , Y. Li","doi":"10.1016/j.ijfatigue.2025.109018","DOIUrl":"10.1016/j.ijfatigue.2025.109018","url":null,"abstract":"<div><div>Gradient structures fabricated using plastic deformation methods have been demonstrated to exhibit excellent fatigue performances. However, achieving an optimal gradient structure remains challenging because of methodological limitations. In this study, nickel plates with varying grain-size gradient structures (GSs) were synthesized in a controllable manner via direct-current electrodeposition. Fatigue tests revealed that the GS samples, ranging from coarse grains (CGs, 4 μm) to nano-grains (NGs, 40 nm), exhibited higher fatigue strengths compared to the homogeneous CG sample. Detailed observations showed that cracks were initiated in the surface layers of the GS samples, while severe plastic deformation was mitigated, demonstrating a superior co-deformation capability. An optimized structure with a linear hardness gradient ranging from 2.3 to 3.4 GPa and grain sizes ranging from CGs to ultrafine grains (UFGs, 170 nm) led to a further enhanced fatigue performance, achieving a fatigue limit of 325 MPa and a fatigue ratio of 0.38. This improved performance was attributed to the ability of the structure to disperse cyclic deformation and suppress stress concentration. These findings highlight the potential of controllably synthesized grain-size gradient structures to enhance the high-cycle fatigue properties of nickel plates.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109018"},"PeriodicalIF":5.7,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143877465","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}
Aleks Vainionpää, Pedro A. Ferreirós, Tommi Seppänen, Zaiqing Que
{"title":"Microstructural insights into effects of pressurized water reactor environment and cyclic loading parameters on the low cycle fatigue behavior of 316L stainless steel","authors":"Aleks Vainionpää, Pedro A. Ferreirós, Tommi Seppänen, Zaiqing Que","doi":"10.1016/j.ijfatigue.2025.109016","DOIUrl":"10.1016/j.ijfatigue.2025.109016","url":null,"abstract":"<div><div>Austenitic stainless steels, commonly used in light water reactor coolant environments, can be susceptible to environmentally assisted fatigue due to non-monotonic loading conditions, primarily associated with load-follow operations, thermal transients, or intermittent plant shutdowns and start-ups. The effects of a pressurized water reactor (PWR) environment containing hydrogen and cyclic loading parameters on the low cycle fatigue (LCF) behavior of 316L stainless steel were investigated by comprehensive striation spacing evaluation and advanced microscopic characterizations. The exposure to a PWR environment results in a decreased LCF lifetime, an enhanced fatigue crack initiation and an accelerated fatigue crack growth rate of 316L austenitic stainless steel. The interaction between hydrogen and localized deformation contributes to the observed acceleration of fatigue crack growth rate in a PWR environment. The evaluation of the effect of waveform (periodic underload PUL, periodic overload POL and constant amplitude sawtooth CA) shows that both PUL and POL reduce the low cycle fatigue lifetime, accelerate the fatigue crack growth rate and advance the cycle where fatigue crack initiation occurs compared to CA loading. LCF waveform strongly influences the shear band formation, localization of plastic deformation and stress state.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109016"},"PeriodicalIF":5.7,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874684","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}
Sheng-Wang Zhang , Hao-Peng Qiao , Xue-Yan Song , Zhao-Hui Lu , Chun-Qing Li
{"title":"Time-dependent fatigue reliability analysis of heavy-haul railway steel bridges based on coupled train-track-bridge dynamic analysis","authors":"Sheng-Wang Zhang , Hao-Peng Qiao , Xue-Yan Song , Zhao-Hui Lu , Chun-Qing Li","doi":"10.1016/j.ijfatigue.2025.109011","DOIUrl":"10.1016/j.ijfatigue.2025.109011","url":null,"abstract":"<div><div>Due to the severity and sudden onset of damage, fatigue failure in heavy-haul railway bridges has become a critical concern for all stakeholders. This study develops a comprehensive time-dependent fatigue reliability framework based on stress range analysis, where stress ranges, regarded as the primary drivers of fatigue damage, are systematically characterized for their stochastic and dynamic nature. The developed framework integrates three key innovations: (1) implementation of a coupled train-track-bridge system-based stochastic dynamic analysis, enhancing conventional static methods to more accurately characterize the dynamical development of the stress range; (2) development of a continuous nonstationary stochastic process model for the stress range that surpasses traditional stationary assumptions in realism; and (3) application of a fourth-moment transformation method for time-dependent reliability analysis involving nonstationary stochastic processes. The proposed framework is validated through application to an actual heavy-haul railway steel bridge, revealing that both the stress range and the fatigue limit state function exhibit time-dependent, nonstationary, and non-Gaussian characteristics. Notably, incorporating dynamic analysis under a nonstationary assumption proves to be critical, as conventional methods tend to overestimate fatigue reliability. This study provides valuable insights for engineers in the design, assessment, and management of railway bridges under stochastic fatigue loads.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109011"},"PeriodicalIF":5.7,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143869041","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}
{"title":"Acoustic emission-driven fatigue damage evolution equation and life prediction of composite laminates","authors":"Fan Dong , Yazhi Li , Biao Li","doi":"10.1016/j.ijfatigue.2025.109012","DOIUrl":"10.1016/j.ijfatigue.2025.109012","url":null,"abstract":"<div><div>Conventional acoustic emission (AE) establishes correlations between signals and damage, often relying on machine learning or threshold-based approaches. These methods either lack quantitative rigor or depend on black-box models with limited interpretability. To address these limitations, this study leverages AE signals to develop a physics-informed damage evolution equation, capturing the underlying physical mechanisms governing fatigue damage in composite laminates. By integrating AE signal analysis with a phenomenological framework, the proposed model extracts damage state from AE data and incorporates material-specific physical parameters to accurately describe damage progression and predict fatigue life. This approach characterizes the fatigue damage evolution using AE cumulative energy, effectively reconstructing the three critical stages of fatigue: primary damage, steady-state damage, and accelerated damage. AE data from plain-woven glass fiber/cyanate composite laminate (GFRP) and multidirectional symmetric carbon fiber CCF800H/AC531 laminates (CFRP) with open-hole subjected to tension–tension loading were utilized for validation. The results showed that the predicted fatigue life for GFRP and CFRP falls within 2 and 2.5 times their respective error bands. These findings underscore the potential of this physics-guided AE-based methodology for applications in structural health monitoring and fatigue life prediction of composite materials.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109012"},"PeriodicalIF":5.7,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874683","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}
{"title":"Comparison of tensile and LCF behaviour of heat-treated Inconel 718 printed by LPBF and LW-DED at different temperatures","authors":"Vivek Kumar Singh , Debaraj Sahoo , Anish Ranjan , Murugaiyan Amirthalingam , Shyamprasad Karagadde , Sushil K. Mishra","doi":"10.1016/j.ijfatigue.2025.109010","DOIUrl":"10.1016/j.ijfatigue.2025.109010","url":null,"abstract":"<div><div>This study investigates the effect of processing routes on the tensile and low-cycle fatigue (LCF) performance of Inconel 718 at room temperature (RT) and elevated temperatures fabricated via Laser Powder Bed Fusion (LPBF) and Laser Wire Direct Energy Deposition (LW-DED) under identical heat treatment conditions. Despite the contrasting differences in the solidification microstructures, including dendritic arm spacing, grain size, and the size of secondary phases, the as-printed tensile and LCF behavior of both routes remained comparable. On the contrary, heat-treated LPBF samples exhibited significantly better mechanical properties than LW-DED conditions due to the influence of printing signatures. Among all conditions, LPBF-STA demonstrated the highest tensile strength and LCF performance, surpassing wrought Inconel 718. In contrast, while the LW-DED-STA exhibited good tensile strength and ductility, it demonstrated a significantly poor LCF performance, especially at 650°C. The cyclic softening in the STA samples was due to a combined variation in both back stress and friction stress, attributed to the reduction in the size of γ<em>’’</em>-precipitates. The work reveals the similarity and contrast in the mechanical properties of two processing routes in the as-printed and heat-treated conditions, respectively, and provides insights that are helpful to design Inconel 718 components.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109010"},"PeriodicalIF":5.7,"publicationDate":"2025-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143855439","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}
{"title":"Experimental study on Fe-SMA strengthening technique for cope hole fatigue cracks in orthotropic steel bridge decks","authors":"Zhilin Lyu , Xu Jiang , Xuhong Qiang","doi":"10.1016/j.ijfatigue.2025.109003","DOIUrl":"10.1016/j.ijfatigue.2025.109003","url":null,"abstract":"<div><div>Iron-based shape memory alloys (Fe-SMAs) have emerged as innovative smart materials for structural rehabilitation. However, their application on fatigue repairing in steel bridges remains limited. This study aims to examine the effectiveness of Fe-SMA strengthening for repairing fatigue-cracked cope holes in orthotropic steel bridge deck (OSD). Experimental investigations were conducted on three full-scale specimens: one reference and two strengthened with unilateral and bilateral Fe-SMA configurations, respectively. Then a comprehensive fatigue testing was performed to evaluate failure mechanisms and fatigue performance improvement of diaphragm cope hole cracks. Finally, the feasibility of Fe-SMA strengthening for such cracks was verified through stress monitoring on an in-service steel bridge. Results demonstrate that Fe-SMA strengthening achieves a synergistic effect of prestressing introduction and local rigidity enhancement at the damaged cope holes, substantially improving fatigue performance. The equivalent fatigue lives of repaired cope hole increased by factors of 10.9 to 62. Bilateral reinforcement exhibited superior fatigue improvement compared to unilateral reinforcement, achieving complete suppression of crack propagation. Field monitoring revealed that under random traffic loading, all stress amplitudes at the cracked cope hole details after combined Fe-SMA bonding and stop-hole method were below the constant amplitude fatigue limit (CAFL), satisfying infinite-life design criteria.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109003"},"PeriodicalIF":5.7,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143855438","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}
B.S. Gong , Z.J. Zhang , H.W. Wang , R. Liu , H.Z. Liu , H. Wang , G. Purcek , M. Demirtas , H. Yanar , Z.F. Zhang
{"title":"A novel surface strengthening technique for enhancing fatigue properties of 6061 Al alloy","authors":"B.S. Gong , Z.J. Zhang , H.W. Wang , R. Liu , H.Z. Liu , H. Wang , G. Purcek , M. Demirtas , H. Yanar , Z.F. Zhang","doi":"10.1016/j.ijfatigue.2025.109000","DOIUrl":"10.1016/j.ijfatigue.2025.109000","url":null,"abstract":"<div><div>A new surface spinning rolling (SR) strengthening technique was developed to enhance the fatigue properties of 6061 Al alloy. The traditional shot peening (SP) process can strengthen the sample’s surface, but it increases surface damage, which seriously hinders the improvement of fatigue performance. However, the SR process not only introduces a high residual compressive stress and a hardened layer on the sample surface but also remarkably lowers the surface roughness. Moreover, the SR treatment formed a gradient microstructure on the surface layer of 6061 Al alloy, effectively postponing the initiation and propagation of fatigue cracks. Fatigue experiments demonstrate that after SR treatment, the fatigue strength of 6061 Al alloy increases by 17.9 %, from 223 MPa to 263 MPa. This study demonstrates the significant advantages by the SR process in producing high fatigue-resistant Al alloy components.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109000"},"PeriodicalIF":5.7,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860108","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}
Herwig Mayer , Michael Fitzka , Harald Rennhofer , Helga C. Lichtenegger , Stefano Checchia , Florian Rödl , Jan Becker , Frederic Lauer
{"title":"Ultrasonic fatigue of cast aluminium under cyclic compression and of superelastic Nitinol in the synchrotron","authors":"Herwig Mayer , Michael Fitzka , Harald Rennhofer , Helga C. Lichtenegger , Stefano Checchia , Florian Rödl , Jan Becker , Frederic Lauer","doi":"10.1016/j.ijfatigue.2025.109009","DOIUrl":"10.1016/j.ijfatigue.2025.109009","url":null,"abstract":"<div><div>Ultrasonic fatigue testing is used for the first time to study the very high cycle fatigue (VHCF) properties of cast aluminium AlSi8Cu3–T6 under purely cyclic compression loading (load ratio <em>R</em> = –∞). Formation of numerous shear cracks and disruption of large material volumes caused failures under cyclic compression, whereas casting porosities were preferential sources of cracks leading to early failures at load ratios <em>R</em> = –1 and <em>R</em> = 0. The Goodman straight line approximation well predicts the mean stress sensitivity for cyclic tension, whereas the FKM guideline overestimates it for cyclic tension as well as cyclic compression.</div><div>In–situ ultrasonic fatigue tests in the synchrotron have been performed with superelastic Nitinol. Specimens were subjected to a preloading procedure which led to a multiphase austenitic − martensitic condition. Lattice deformation over an ultrasonic cycle as well as under quasi static condition confirmed similar elastic deformation at 0.1 Hz and 18.3 kHz. Progress of fatigue damage with increasing numbers of ultrasonic cycles was observed in–situ with XRD patterns from the multiphase area. Formation and growth of austenitic bands in formerly martensitic areas was found that led to a progressively increasing specimen stiffness and an increase of stresses in displacement-controlled ultrasonic fatigue tests.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"198 ","pages":"Article 109009"},"PeriodicalIF":5.7,"publicationDate":"2025-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143886138","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}