International Journal of Fatigue最新文献

{"title":"Effect of water saturation on uniaxial constant amplitude tensile fatigue performance of ECC and its statistical analysis of fatigue life","authors":"Shuling Gao ,&nbsp;Qingyuan Xu ,&nbsp;Zhengwen Wang ,&nbsp;Yanping Zhu","doi":"10.1016/j.ijfatigue.2024.108666","DOIUrl":"10.1016/j.ijfatigue.2024.108666","url":null,"abstract":"<div><div>The degree of water saturation has a significant influence on the tensile fatigue properties of Engineered Cementitious Composites (ECC). The half-saturated and saturated state ECC can be rapidly prepared by a vacuum saturation equipment. The fatigue tensile mechanical tests under five tensile stress levels and corresponding studies on the damage morphology, fatigue life, S-N relationship, fatigue strain and fatigue damage on dry, half-saturated, and saturarted state were conducted. The mathematical and statistical analysis method was also utilized to predict ECC’s fatigue life and strength with high confidence and high reliability, providing a reference for assessing structural safety. The study found that free water significantly reduces ECC fatigue strength, with fatigue life decreasing as water content increases. At 2 million cycles, fatigue strength reduction coefficients for 0%, 50%, and 100% water saturation are 0.623, 0.550, and 0.423, respectively. The three-parameter Weibull distribution best describes ECC fatigue life. Using this model, S-N and P-S-N curves were developed, incorporating confidence limits to derive γ-P-S-N relationships, ensuring high confidence and reliability.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108666"},"PeriodicalIF":5.7,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552731","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":"High temperature fatigue behavior of coated and uncoated nickel-based single crystal superalloy DD6: Microstructures evolution, damage mechanisms and lifetime prediction","authors":"Jiaping Li,&nbsp;Xiaochao Jin,&nbsp;Dongxu Li,&nbsp;Jingjing Yang,&nbsp;Xueling Fan","doi":"10.1016/j.ijfatigue.2024.108670","DOIUrl":"10.1016/j.ijfatigue.2024.108670","url":null,"abstract":"<div><div>Thermal barrier coatings (TBCs) are widely used to further extend the lifetime of turbine blades by protecting the blades from high temperature corrosion and oxidation. However, the mechanical behavior of turbine blades is obviously affected by the TBCs. In this study, microstructures evolution, damage mechanisms and life prediction of coated and uncoated nickel-based single crystal (NBSX) superalloy DD6 under isothermal fatigue load were investigated at 980 °C. The effects of TBCs on fatigue failure behavior and lifetime of DD6 were addressed. The results showed that the fatigue lifetime reduced with the increase of load. The effect of TBCs on the fatigue lifetime was related to the stress amplitude, as the effect was beneficial at high stress but almost negligible at low stress. Fracture morphologies showed that the cracks more likely initiated and propagated from basal defects for both coated and uncoated DD6, and the microstructure evolution also showed stress amplitude dependence. The crack density of uncoated DD6 increased first and then decreased with the increase of stress amplitude. However, the TBCs reduced the number of cracks that penetrate into the DD6 substrate, and the stress amplitude exerted a significant effect on crack propagation paths. In addition, the rafting behaviors of the DD6 substrate of coated and uncoated samples was compared, and results showed that TBCs could reduce the rafting degree of DD6. Finally, the fatigue lifetime of coated samples was predicted based on the modified Basquin model, and the prediction results fitted well with the experimental results.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108670"},"PeriodicalIF":5.7,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142552735","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":"MT-CrackNet:A multi-task deep learning framework for automatic in-situ fatigue micro-crack detection and quantification","authors":"Xiangyun Long,&nbsp;Hongyu Ji,&nbsp;Jinkang Liu,&nbsp;Xiaogang Wang,&nbsp;Chao Jiang","doi":"10.1016/j.ijfatigue.2024.108667","DOIUrl":"10.1016/j.ijfatigue.2024.108667","url":null,"abstract":"<div><div>Characterizing fatigue micro-cracks is crucial for understanding the mechanisms and behaviors of material damage. In-situ fatigue testing is an essential method for observing the evolution of fatigue micro-cracks; however, the process often requires significant time, making the measurement of micro-cracks a tedious task. This paper introduces a multi-task deep learning framework called MT-CrackNet, which enables automatic detection and quantification of in-situ fatigue micro-cracks. The framework is capable of recognizing or segmenting multiple tasks such as micro-cracks, text, and scales simultaneously, and its effectiveness is not limited by the magnification of in-situ images. By integrating attention mechanisms and multi-scale strategies, the model enhances its ability to handle long-range dependencies and preserve detail information, accurately identifying and measuring the length of micro-cracks. The effectiveness of the proposed MT-CrackNet is validated through three in-situ fatigue micro-crack propagation experiments.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108667"},"PeriodicalIF":5.7,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142537145","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":"Fatigue properties of non-press-fitted part of full-scale induction-hardened axles of medium-carbon steel for high-speed railway vehicles","authors":"T. Makino ,&nbsp;C. Kozuka ,&nbsp;T. Hata ,&nbsp;T. Kato ,&nbsp;M. Yamamoto ,&nbsp;K. Minoshima","doi":"10.1016/j.ijfatigue.2024.108664","DOIUrl":"10.1016/j.ijfatigue.2024.108664","url":null,"abstract":"<div><div>This study aimed to examine the stress–number of cycles (<em>S–N</em>) curve and fatigue limit of non-press-fitted parts to improve the sophistication of the design method of induction-hardened axles for medium-carbon steel high-speed railway cars. Macroscopic cracks were generated in the non-press-fitted parts of the axles by selecting appropriate fatigue test methods. Thus, the <em>S–N</em> curve was approximated, and the fatigue limit was obtained. The value of an index in the power-law expression of the <em>S–N</em> curve was 11, which was proposed to fatigue damage evaluation standard. Moreover, we constructed a prediction model for high-and very-high-cycle fatigue limits based on the local fatigue-limit approach and fatigue test results of cut-out specimens from several depth regions of induction-hardened axles. The fatigue limit predicted by the model agrees with the experimental high-cycle fatigue limit. The model estimated that the fatigue limit did not decrease in the very-high-cycle regime.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108664"},"PeriodicalIF":5.7,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527883","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":"Fatigue life prediction for Q420qFNH weathering steel welded joints considering the effect of multiple cracks","authors":"Yan Ma ,&nbsp;Chuang Cui ,&nbsp;Qing-hua Zhang ,&nbsp;Kun Tang ,&nbsp;Zhen-yu Cheng","doi":"10.1016/j.ijfatigue.2024.108665","DOIUrl":"10.1016/j.ijfatigue.2024.108665","url":null,"abstract":"<div><div>Multiple semi-elliptical cracks frequently develop at the weld toes of welded joints. These interfering multiple cracks significantly accelerate crack growth rates and reduce the fatigue life of a welded joint compared to a single crack. This study proposes a method for predicting the fatigue life of a welded joint with multiple cracks, considering weld toe amplification effect, multiple crack interference amplification effect, and crack closure effect. The method is validated through fatigue tests on Q420qFNH weathering steel welded joints. The main factors influencing the interference amplification effect are investigated, and theoretical formulas for the interference amplification factor of the stress intensity factor are derived using the finite element method and the superposition principle. The initiation, aggregation, and morphological evolution during the propagation process of multiple cracks is accurately simulated, and the fatigue life of both cruciform-welded and butt-welded joints is predicted. Additionally, a quantitative analysis is conducted to assess the impact of the number of fatigue cracks on fatigue strength. The results indicate that the interference amplification effect of cracks depends on their distance and mainly affects the surface point where the crack front is closest. The proposed fatigue life prediction method can accurately estimate the fatigue life of Q420qFNH steel welded joints considering the effect of multi-cracks. The interference and coalescence of multiple cracks significantly reduce the fatigue life of welded joints. An increase in the number of fatigue cracks notably decreases the fatigue strength.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108665"},"PeriodicalIF":5.7,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527885","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":"Corrosion and corrosion-fatigue properties of composite ceramic coated aluminum alloy formed by combining surface nanocrystallization pre-treatment, micro-arc oxidation, and sealing post-treatment","authors":"Kaixin Su ,&nbsp;Jiwang Zhang ,&nbsp;Shengchuan Wu ,&nbsp;Jinfa Guan ,&nbsp;Hang Li ,&nbsp;Dongdong Ji ,&nbsp;Honglan Xie","doi":"10.1016/j.ijfatigue.2024.108661","DOIUrl":"10.1016/j.ijfatigue.2024.108661","url":null,"abstract":"<div><div>The aluminum alloy components of the high-speed railway catenary, when exposed to the corrosive media in coastal regions, are confronted with a significant issue of corrosion-fatigue failure. Therefore, this study prepares a kind of composite ceramic coating formed by combining shot peening surface nanocrystallization pre-treatment, micro-arc oxidation (MAO) ceramic coating, and acrylic resin sealing post-treatment on 6082-T6 aluminum alloy used for high-speed railway catenary. Then, the corrosion and corrosion-fatigue properties of composite ceramic coated 6082-T6 aluminum alloy are investigated. Results indicate that the pre-treatment increases the thickness of ceramic coating, however results in larger internal defects connecting ceramic coating’s outer surface, leading to inferior corrosion resistance compared to plain ceramic coatings. However, owing to the presence of compressive residual stress and grain-refined layers within the substrate beneath the ceramic coating, ceramic coated specimens subjected to the pre-treatment exhibit superior corrosion-fatigue properties compared to plain coated specimens. Additionally, the post-treatment effectively reduces coating porosity and enhances corrosion resistance. In conclusion, the composite ceramic coating in this paper is demonstrated to exhibit a combination of superior corrosion resistance, fatigue and corrosion-fatigue properties.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108661"},"PeriodicalIF":5.7,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527879","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":"Small fatigue crack behavior of CP-Ti in thin-walled cruciform specimens under biaxial loading","authors":"Le Chang,&nbsp;Zhuowu Wang,&nbsp;Hongpeng Xie,&nbsp;Chao Lv,&nbsp;Wei Zhang,&nbsp;Changyu Zhou","doi":"10.1016/j.ijfatigue.2024.108662","DOIUrl":"10.1016/j.ijfatigue.2024.108662","url":null,"abstract":"<div><div>This study investigates the small fatigue crack propagation behavior of commercially pure titanium (CP-Ti) using thin-walled cruciform specimens under in-plane biaxial loading, considering the effects of biaxial ratio and phase angle. Increasing phase angle results in more secondary cracks merging with main cracks perpendicular to the rolling direction (RD) and transverse direction (TD), a phenomenon attributed to the rise in shear stress that accelerates main crack growth. Higher loading biaxiality or a lower phase angle leads to decreased crack propagation rates and increased biaxial fatigue life. Electron backscatter diffraction (EBSD) analysis reveals that when the maximum normal stress aligns with the RD, prismatic slip primarily governs crack propagation, thereby accelerating crack propagation rates. Conversely, alignment with the TD reduces prismatic slip activity and crack propagation rates. Under equi-biaxial loading, prismatic slip activity decreases further, and crack propagation is dominated by multiple slip and twinning, consequently resulting in the slowest propagation rates. Additionally, a higher proportion of prismatic slip under high phase angle also accelerates crack propagation. Finally, incorporating Findley equivalent stress into the Chapetti model, which considers the crack length-dependent threshold effect, a highly accurate biaxial small fatigue crack propagation rate model is proposed.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108662"},"PeriodicalIF":5.7,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527895","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":"Simulation of fatigue crack growth in aluminium alloy 7075-T7351 under spike overload and aircraft spectrum loading","authors":"K.F. Walker ,&nbsp;A. Grice ,&nbsp;J.C. Newman Jr. ,&nbsp;R. Zouev ,&nbsp;S.A. Barter ,&nbsp;D. Russell","doi":"10.1016/j.ijfatigue.2024.108660","DOIUrl":"10.1016/j.ijfatigue.2024.108660","url":null,"abstract":"<div><div>The trend towards virtual testing and digital-twin assisted management means that the accurate and reliable simulation of fatigue crack propagation behaviour is more important than ever. Reliable but conservative approaches to support this are in widespread use in the aerospace industry. Nevertheless, the conservatism comes at a significant cost in terms of reduced structural life and an increased ongoing inspection requirement and, as such leads to questions about the economic burden of these approaches. Recent comparisons between blind predictions and test results revealed the extent of the issue for cracking in aluminium alloy 7075-T7351 coupons with configuration and loading representative of military transport aircraft wing skins. The current models were generally conservative by a factor of two or more in terms of crack propagation life. This suggested that there was significant scope to improve the modelling to better reflect all the complex contributing factors. The current work has investigated the issue of changes in the crack front constraint as the crack progresses from a state of high constraint (close to plane strain) to a lower constraint (approaching plane stress). This issue was investigated both experimentally and with the development of an improved analytical model. A test program was conducted on several specimens, loaded under constant-amplitude, constant-amplitude with spike-overloads and a variable amplitude spectrum. Crack-opening stress levels were measured at key points in the tests and the results were used to develop and evaluate improved modelling approaches. The improved model was generally able to predict crack growth within about ± 30 % of that demonstrated along with the correct form of the crack growth, which is a significant advance and will lead to reduced costs and increased safety.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108660"},"PeriodicalIF":5.7,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142537146","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":"Fatigue behavior of additively manufactured 316L stainless steel: Competition between the effects of defects and microstructure","authors":"Hugo Roirand ,&nbsp;Anis Hor ,&nbsp;Benoit Malard ,&nbsp;Nicolas Saintier","doi":"10.1016/j.ijfatigue.2024.108658","DOIUrl":"10.1016/j.ijfatigue.2024.108658","url":null,"abstract":"<div><div>Laser Powder Bed Fusion (LPBF) process, is becoming more and more widespread in industry. The possibilities of microstructural control offered by this process are an opportunity to study the contribution of the different length scales of microstructure to the fatigue behavior. This paper is devoted to the understanding of this fatigue behavior resulting from the interactions between the process induced defects and the different polycrystal length scales. Two distinct defect − microstructure competition regimes have been identified. The first concerns microstructures containing large Lack of Fusion (LoF) defects. These LoFs drastically reduce the fatigue life, while microstructure has no influence on the fatigue strength. The second regime concerns microstructures containing small defects. A limited effect of the polycrystalline microstructure was revealed. Furthermore, this paper demonstrates that the ratio between damage initiation defect size and grain size, used in literature to describe the defect and microstructure sensitivity of fatigue strength, is not applicable over a wide range of defects and microstructures, such as obtained by additive manufacturing processes. Finally, the comparison between the fatigue behavior of different microstructure and defect features shows that producing a finer microstructure improves fatigue strength despite the presence of a significant defect population.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108658"},"PeriodicalIF":5.7,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527882","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":"A novel prediction method for rolling contact fatigue damage of the pearlite rail materials based on shakedown limits and rough set theory with cloud model","authors":"Yulong Xie ,&nbsp;Haohao Ding ,&nbsp;Zhiyong Shi ,&nbsp;Enrico Meli ,&nbsp;Jun Guo ,&nbsp;Qiyue Liu ,&nbsp;Roger Lewis ,&nbsp;Wenjian Wang","doi":"10.1016/j.ijfatigue.2024.108654","DOIUrl":"10.1016/j.ijfatigue.2024.108654","url":null,"abstract":"<div><div>Evaluation and prediction of wheel-rail rolling contact fatigue (RCF) damage can provide important theoretical guarantees for the service safety of wheels and rails and help make maintenance easier to plan. This study aims to develop a novel method for evaluating and predicting RCF damage of the pearlite rail materials with various initial shear yield strengths (<em>k</em>_e). Based on the rough set mathematical theory incorporated within the cloud model of the comprehensive evaluation index (<em>P</em>₀/<em>k</em>_e*<em>μ</em>^t), a novel evaluation and prediction method for RCF damage states of various pearlite rail materials was constructed using the shakedown limits for pearlite rail materials with various initial shear yield strengths. To develop this novel prediction method, different evaluation indices for RCF damage states were designed. A comprehensive certainty approach was introduced to quantitatively analyze the actual measured values of distinct evaluation indices that corresponds to different RCF damage states, wherein the maximum value rule was applied. Moreover, the prediction results were confirmed after further verifying using the actual measured value of the <em>P</em>₀/<em>k</em>_e*<em>μ</em>^t. The results indicated that the predicted results were consistent with the test outcomes. The key feature of this prediction method was that it involved both the intrinsic shear yield strength of evaluated pearlite rail materials and wheel-rail rolling contact variables. On the basis of the two-dimensional classical shakedown map, a three-dimensional shakedown limit diagram for rail materials with varying initial shear yield strengths was further constructed using this novel prediction method. The three-dimensional shakedown limit diagram featured an inclined curved surface. As the initial shear yield strength of the pearlite rail materials increased, the curved surface tilted downward, indicating that an increase in the initial <em>k</em>_e value of the pearlite rail materials could result in a lower shakedown limit.</div></div>","PeriodicalId":14112,"journal":{"name":"International Journal of Fatigue","volume":"190 ","pages":"Article 108654"},"PeriodicalIF":5.7,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142527880","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}