Article
Engineering, Mechanical
Kun Yang, Qi Huang, Bin Zhong, Yong Jie Liu, Chao He, Hanqing Liu, Ning Su, Qingyuan Wang, Qiang Chen
Summary: The research showed that increasing the colony content in bimodal titanium alloys can enhance the high cycle fatigue and very high cycle fatigue properties. However, crack initiation life is less sensitive to changes in microstructure compared to fatigue crack growth life. As fatigue life increases, the impact of microstructure evolution on fatigue resistance gradually decreases.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2021)
Article
Engineering, Mechanical
Garrett A. Webster, Alireza Behvar, Shawkat I. Shakil, Riyanka Ribble, Kathleen Chou, Ajay Krishnamurthy, Shahab Zekriardehani, Joseph Lawrence, Sajad Shakerin, Mohsen Mohammadi, Andrea Tridello, Davide S. Paolino, Meysam Haghshenas
Summary: This paper presents a comprehensive study on the VHCF characterization of WAAM ER100S-G steel, revealing its extended fatigue life behavior and failure mechanisms. The findings provide valuable insights into optimizing design guidelines for additive manufacturing in high-cycle and very high-cycle fatigue domains.
ENGINEERING FAILURE ANALYSIS
(2023)
Article
Crystallography
Baohua Nie, Shuai Liu, Yue Wu, Yu Song, Haiying Qi, Binqing Shi, Zihua Zhao, Dongchu Chen
Summary: The effect of low cycle fatigue (LCF) predamage with no precracks on very high cycle fatigue (VHCF) properties and crack initiation characteristics for TC21 titanium alloy was investigated. It was found that LCF predamage with less than 5% of fatigue life had minimal impact on fatigue limit but reduced fatigue life. Fatigue cracks initiated on the surface of the specimen at high stress amplitudes, while fatigue cracks initiated below the surface at low stress amplitudes. A combined fatigue damage model was established based on Lemaitre damage theory, and it showed consistency with experimental data. The fatigue crack initiation of specimens with LCF predamage less than 5% accounted for a significant portion of fatigue life.
Article
Mechanics
Hongjiang Qian, Zhiyong Huang, Yeting Xu, Qikai Zhou, Jian Wang, Jiebin Shen, Zeshuai Shen
Summary: This study uses Monte Carlo Simulation (MCS) to expand the low VHCF dataset and proposes a dynamic recurrent machine learning model, which significantly improves the predictive performance of ML models. The challenge of predicting the life of sparse VHCF specimens is solved, reducing the cost and time of VHCF prediction.
ENGINEERING FRACTURE MECHANICS
(2023)
Review
Engineering, Mechanical
Andrea Tridello, Carlo Boursier Niutta, Massimo Rossetto, Filippo Berto, Davide S. Paolino
Summary: The paper provides a comprehensive review of models for stress-life relation in Very High Cycle Fatigue (VHCF), covering different methods, failure modes, statistical distribution of fatigue life, and characteristics of P-S-N curves. The research aims to highlight the strengths and weaknesses of current models and guide future research directions.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Tao Shi, Jingyu Sun, Jianghua Li, Guian Qian, Youshi Hong
Summary: Using machine learning models and data interpolation, the influence of defect features on the fatigue performance of selective laser melted AlSi10Mg alloys was investigated. The results showed that increasing defect distance, circularity, and layer thickness improved fatigue life, while increasing stress amplitude, stress ratio, and defect size decreased fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Review
Engineering, Mechanical
Riccardo Caivano, Andrea Tridello, Giorgio Chiandussi, Guian Qian, Davide Paolino, Filippo Berto
Summary: This paper provides a comprehensive literature review on the very high cycle fatigue (VHCF) response of materials produced through additive manufacturing (AM) processes. Experimental results on VHCF response of various specimens produced through different AM processes are summarized. The main factors affecting the VHCF response of AM materials are compared and critically analyzed.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2021)
Article
Materials Science, Multidisciplinary
Xiangnan Pan, Leiming Du, Guian Qian, Youshi Hong
Summary: This study investigates the behavior of very-high-cycle fatigue (VHCF) in metallic materials such as aluminum alloys and high-strength steels. The research reveals that in additively manufactured AlSi10Mg alloy, crack initiation and growth mechanisms are distinct from those in high-strength steels, but demonstrate a similar characteristic region of crack initiation known as fine granular area (FGA).
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2024)
Article
Crystallography
Baohua Nie, Shuai Liu, Yue Wu, Yu Song, Haiying Qi, Binqing Shi, Zihua Zhao, Dongchu Chen
Summary: VHCF tests were conducted on TC21 titanium alloy under variable amplitude loading. The cumulative fatigue life of low stress amplitude was significantly reduced by the high/low stress block, and fatigue crack initiation shifted from the subsurface under constant loading to the surface under stress block. A fatigue damage model of two-step stress block was established based on continuum damage mechanics, which provided a good prediction of cumulative fatigue life. The cumulative fatigue damage of the stress block was influenced by stress amplitude and cycle ratio, determining the stress fatigue damage and its interaction damage. The surface crack initiation in the stress block accelerated fatigue damage of low stress amplitude, leading to reduced cumulative life.
Article
Engineering, Mechanical
Jun Li, Zhengmao Yang, Guian Qian, Filippo Berto
Summary: This study proposed an ML model for VHCF analysis, enlarged dataset size through Monte Carlo simulation, and achieved good prediction accuracy.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Bernd M. Schoenbauer, Suraj S. More, Guillermo E. Morales-Espejel, Herwig Mayer
Summary: The influence of temperature on the very high cycle fatigue properties of three high carbon chromium bearing steels (52100, 52100-VIM/VAR and M50-VIM/VAR) was investigated. Interior defect-initiated cracking was the dominant failure mechanism at all temperatures. Nonmetallic inclusions were the origin of fracture for 52100 while carbides were the origin for 52100-VIM/VAR and M50-VIM/VAR. The fatigue strength at 300°C decreased significantly compared to 22°C, with 52100 steels experiencing a decrease of 56-57% and M50 a decrease of 41%.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Michael Fitzka, Mourad Moalla, Herwig Mayer
Summary: The ultrasonic fatigue testing of high carbon chromium bearing steel 100Cr6 (SAE 52100; JIS SUJ2) was conducted to investigate the Very high cycle fatigue (VHCF). Fatigue limits were observed at compressive mean stresses with minimum stresses equal to compressive yield stress (sigma CY) and at a load ratio of -1. However, no fatigue limit below 10(9) cycles was found for a load ratio of -1. Cracks leading to VHCF failures were only found to initiate at interior inclusions. The fatigue limit was determined by the maximum stress intensity factor of a load cycle being below the effective threshold stress intensity factor.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Chemistry, Physical
Lennie Abdullah, Salvinder Singh Karam Singh, Shahrum Abdullah, Ahmad Kamal Ariffin, Syifa Syuhaidah Meor Zainal
Summary: The aim of this paper is to characterise the fatigue reliability for various random strain loads under extreme value distribution while considering the cycle sequence effect condition in fatigue life prediction. The established strain-life models considered some factors but excluded the load sequence effect. The study proposes an effective strain damage model for a fatigue reliability assessment under extreme conditions with higher reliability and provides fatigue life prediction when subjected to cycle sequence effects.
Article
Engineering, Mechanical
Pedro R. da Costa, Masoud Rahaeifard, Diogo Montalva, Luis Reis, Manuel Freitas
Summary: Ultrasonic fatigue specimens require rigorous design to ensure resonance vibration at high frequencies and desired mode shapes. Existing analytical methods for uniaxial tension-compression or pure torsion specimens limit the range of experiments. This paper proposes a semi-analytical formulation for complex ultrasonic specimen geometries under multiaxial tension-torsion, showing good correlation with numerical simulations. This work can facilitate the design and conduct of more varied and efficient ultrasonic fatigue experiments.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Tsuyoshi Miyakoshi, Takeru Atsumi, Kensuke Kosugi, Atsushi Hosoi, Terumasa Tsuda, Hiroyuki Kawada
Summary: This paper investigates the transverse crack initiation behaviors of carbon fiber-reinforced plastics (CFRPs) in the high-cycle and very high cycle regimes. The fatigue behavior of cross-ply CFRP laminates formed with T800S/2592 prepreg was studied by using an ultrasonic fatigue testing system. The results show that the slope of the S-N diagram for transverse crack initiation decreases linearly within a certain number of cycles and levels off after a certain number of cycles, and no cracks were observed under a certain stress.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Chiara Colombo, Andrea Tridello, Ana Paula Pagnoncelli, Carlo Alberto Biffi, Jacopo Fiocchi, Ausonio Tuissi, Laura Maria Vergani, Davide Salvatore Paolino
Summary: Three techniques for assessing the fatigue response of AMed parts were compared and proved to be effective, with infrared thermography and ultrasonic fatigue tests identifying the most critical defects.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Carlo Boursier Niutta, Andrea Tridello, Davide S. S. Paolino
Summary: In this paper, the fatigue design of AM components is addressed through Topology Optimization. Two defect-driven methodologies, which model the fatigue response in the finite life range and account for the experimental scatter, are compared. The optimal topologies of a cantilever beam and of an engine rod are determined and compared, showing that the defect-distribution method is the most conservative and the stress-gradient method can also be reliably applied in the case of uniform stress distribution, as in the engine rod.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
A. Tridello, D. S. Paolino
Summary: This paper analytically derives the statistical distribution of total strain and fatigue life in the LCF-HCF life range, based on the Coffin-Manson and Morrow model. Parameter estimation using the maximum likelihood principle allows consideration of both failures and runout specimens. Additionally, a straightforward procedure for design curve estimation based on the likelihood ratio confidence lower bound is developed. The proposed model is validated with literature datasets on steel and aluminum alloys, demonstrating its effectiveness and reliability compared to existing models.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Andrea Tridello, Carlo Boursier Niutta, Filippo Berto, Davide S. Paolino
Summary: This paper investigates the influence of a blunt notch on the very high cycle fatigue (VHCF) response of SLM Ti6Al4V specimens. Ultrasonic fully reversed tension-compression tests were conducted up to 10^9 cycles on unnotched specimens and specimens with a blunt notch. Unnotched specimens exhibited slightly larger fatigue response, but with limited differences. Fatigue failures in both types of specimens originated from defects, which were bigger in unnotched specimens due to the different risk volume and size effect. The interactions between notch, stress gradient, and defect size distribution need to be taken into account for proper assessment of the influence of the notch on VHCF response.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
A. Ciampaglia, A. Tridello, D. S. Paolino, F. Berto
Summary: In this paper, machine learning algorithms are utilized to predict the fatigue response of Additive Manufacturing (AM) components. It is found that manufacturing defects and microstructures, which are influenced by process parameters and heat treatments, play significant roles in determining the fatigue response.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Chemistry, Physical
Carlo Boursier Niutta, Raffaele Ciardiello, Andrea Tridello, Davide S. Paolino
Summary: In recent years, there has been a significant increase in the interest in sustainability in many industrial sectors. This can be achieved through lightweight design and eco-friendly manufacturing processes. One potential solution to the concerns over the use of non-recyclable thermoset composite materials is to replace the thermoset matrix with a recyclable or renewable matrix, such as a bio-based resin. Experimental tests have shown that composites made with bio-based resin have similar mechanical properties to those made with epoxy resins, making them a reliable substitute that reduces the carbon footprint.
Article
Materials Science, Multidisciplinary
Andrea Tridello, Carlo Boursier Niutta, Filippo Berto, Davide Salvatore Paolino
Summary: This study investigates the influence of size-effects on the very high cycle fatigue (VHCF) response of materials through ultrasonic fatigue tests on an aluminum alloy and four steels used in automotive applications. The experimental results are analyzed with an innovative statistical model based on the weakest-link principle and stress gradient within the specimens, revealing that size-effects significantly impact the VHCF response of the investigated materials. This further emphasizes the importance of properly verifying and accounting for size-effects in designing structural components against VHCF failure.
MATERIALS PERFORMANCE AND CHARACTERIZATION
(2023)
Article
Engineering, Mechanical
C. Boursier Niutta, D. S. Paolino, A. Tridello
Summary: This study proposes an experimental-numerical methodology for identifying the lower bound design curve of lattice structures under quasi-static compressive and impact tests. It is validated on an octet truss lattice structure made of an additively manufactured AlSi10Mg alloy. The defect size distribution is assessed through micro computed tomography, and the mechanical tests are simulated using a Finite Element Model (FEM) with a local reduction in truss diameter. The FEM accurately predicts the mechanical behavior, and the lower bound design curve is determined through statistical considerations for safe component design.
ENGINEERING FAILURE ANALYSIS
(2023)
Article
Engineering, Mechanical
Alessio Centola, Alberto Ciampaglia, Andrea Tridello, Davide Salvatore Paolino
Summary: The aim of this paper is to predict the fatigue life of SLMed Ti6Al4V components using machine learning techniques. The methods have been trained and validated using experimental data to assess their reliability. The study also investigates the impact of SLM process parameters on fatigue life.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Davide Pederbelli, Andrea Tridello, Davide Salvatore Paolino, Luca Goglio
Summary: This paper investigates the effects of stress singularities on the high cycle fatigue performance of adhesively bonded butt joints. It is found that removing the singularity significantly increases the joint life, but leads to higher scatter data compared to the original specimen configuration.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Miloslav Kepka, Miloslav Kepka Jr, Radovan Minich
Summary: This paper focuses on the fatigue life evaluation of the bodywork of a new articulated electric (battery) bus. The findings resulted in recommendations to improve the operational reliability of a particular vehicle and provided challenges for future research.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
T. Dusautoir, B. Berthel, S. Fouvry, P. Matzen, K-D. Meck
Summary: This study investigates the impact of post-processing treatments on the fatigue limit of additive manufactured Ti-6Al-4V under stress gradients, with a focus on surface integrity.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Zhuofan Xia, Di Wu, Xiaochen Zhang, Jianqiu Wang, En -Hou Han
Summary: The study reveals the surface-initiated rolling contact fatigue (RCF) failure mechanism under heavy load and initial high roughness surface. The results indicate that precursor of collapsed morphology and nanocrystalline layer are the main factors causing lower RCF life with high roughness compared to low roughness surfaces. The spalling failure initiating from low roughness surface under heavy load is strongly dependent on surface plastic deformation.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Daniel Gren, Knut Andreas Meyer
Summary: Rolling contact loading can cause plastic deformation and fatigue cracks. Current rail standards do not consider the effect of plasticity on mechanical behavior. This study proposes a new method for evaluating the fatigue life of deformed material and finds that superimposed compressive axial loads can increase fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
R. Kumar, S. Sanyal, J. Bhagyaraj, E. Hari Krishna, S. Mukherjee, K. Prasad, S. Mandal
Summary: This study investigates the thermomechanical fatigue (TMF) behavior of Timetal 834 alloy under different loading conditions. The results show that the alloy exhibits different cyclic hardening and softening responses at different strain amplitudes. The strain amplitude and phase angle have significant effects on the TMF life.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Kai Donnerbauer, Tobias Bill, Peter Starke, Ruth Acosta, Bharath Yerrapa, Christian Boller, Klaus Heckmann, Frank Walther
Summary: Given the aging of nuclear power plants, it is important to develop methods for evaluating the integrity of components and structures in nuclear engineering. Suitable nondestructive testing methods can detect material degradation and determine its fatigue life. This study utilized various NDT parameters and scanning electron microscopic methods to explore the relationship between microstructure evolution and NDT data.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Liuyong He, Jiang Zheng, Tianjiao Li, Houkun Zhou, Lihong Xia, Bin Jiang
Summary: This study quantitatively analyzed the effects of precipitates on the deformation mode, cracking mode, and mechanical behavior of WE54 magnesium alloy during low-cycle fatigue. It was found that precipitates promoted the activation of dislocation slip and suppressed the activation of twinning, affecting the cracking mode and mechanical behavior.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Xiangkang Zeng, Conghui Zhang, Wenguang Zhu, Mingliang Zhu, Tongguang Zhai, Xiaomei He, Kangkai Song, Zhuohang Xie
Summary: The cyclic deformation behaviors and damage mechanisms of pure Zr were investigated. The cyclic stress response was mainly influenced by substructure evolutions. Prismatic < a > dislocation slip was identified as the dominant deformation mechanism. Fatigue damage was not only influenced by the initial texture, but also other factors.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Jingyu Yang, Bingbing Li, Yiming Zheng, Gang Chen, Xu Chen
Summary: Heat treatment is used to improve the low-cycle fatigue performance of additive manufactured 316LN stainless steel. The heat-treated material demonstrates initially cyclic hardening followed by softening behavior, and shows a stronger resistance to crack propagation compared to the as-built material, resulting in a longer fatigue life.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Lang Zou, Dongfang Zeng, Xiong Chen, Jun Li, Hai Zhao, Liantao Lu
Summary: This study investigates the competitive relationship between fretting fatigue and plain fatigue in press-fitted railway axles. By changing the depth of the stress relief groove, the plain fatigue limit and fretting fatigue strength were tested. Detailed information was gathered, and an evaluation methodology integrating finite element simulation and the Modified Wohler Curve Method was established. The study concludes that the optimal groove depth, which balances the anti-fatigue capabilities, depends on the number of test cycles.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Davide Leonetti, Koji Kinoshita, Yukina Takai, Alain Nussbaumer
Summary: This paper investigates the fatigue behavior of non-load-carrying transverse welded steel attachments, including fatigue crack monitoring and fracture surface analysis under constant and variable amplitude loading. A procedure is proposed to obtain a Markov transition matrix based on the measured strain signal and to randomly resample the stress history for variable amplitude fatigue tests.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Zhe Zhang, Bing Yang, Yuedong Wang, Shoune Xiao
Summary: This paper presents a method for designing fatigue life prediction models with small sample sizes by handling limited sample data. The method integrates the equivalent structural stress method with the maximum likelihood estimation method and adds reliability verification, resulting in enhanced goodness of fit, stability, and optimized sample quantity.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Cooper K. Hansen, Gary F. Whelan, Jacob D. Hochhalter
Summary: This paper presents a method to address the computational demand issue of computing FIPs using CPFEM by developing an interpretable machine learning model. Genetic programming is used to evolve interpretable expressions of FIPs from microstructure features, and these models can serve as efficient substitutes for CPFEM and be easily integrated into engineering workflows.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Luca Susmel
Summary: This paper discusses the problem of estimating notch fatigue limits using machine learning. The results show that machine learning is a promising approach for designing notched components against fatigue. The accuracy in estimating the fatigue limit can be increased by increasing the size and quality of the calibration dataset, as well as including additional input features.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)
Article
Engineering, Mechanical
Kefeng Gao, Guoqi Tan, Yanyan Liu, Qiang Wang, Qian Tang, Xuegang Wang, Qiqiang Duan, Zengqian Liu, Zhe Yi, Zhefeng Zhang
Summary: Bioinspired architectures have significant effects on material enhancement. This study investigates the fatigue properties of bioinspired ceramic-polymer composites and natural nacre, revealing the close relationship between architectural types, orientations, fatigue performance, and damage mechanisms.
INTERNATIONAL JOURNAL OF FATIGUE
(2024)