Article
Engineering, Mechanical
Tianyu Zhang, Yu Wang, Chi Zhang, Lingyu Wang, Hongshuang Di, Wei Xu
Summary: Carbide-free bainite (CFB) steel with metastable austenite and refined microstructures shows great potential as an alternative to conventional pearlitic rail and wheel steels. This study investigates the fatigue crack growth (FCG) behavior of CFB steels and compares it with the traditional high-speed railway axle steel (grade DZ2). The CFB steel exhibits higher static mechanical properties and fatigue resistance than the DZ2 steel.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
V. Giannella
Summary: The study focuses on the stochastic nature of fatigue crack-growth in mechanical components and the prediction of residual fatigue life of a railway axle under different input parameters variability. Various sources of uncertainty are considered in the analysis.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Mechanics
Tian Xu, Liantao Lu, Dongfang Zeng, Lang Zou
Summary: In this study, a fretting fatigue crack growth simulation was conducted on a railway press-fitted axle using an actual load spectrum to assess the inspection interval and safety margin. The results were compared to measured crack data to evaluate the effectiveness of different crack orientation criteria. A finite element model was then used to predict the fretting fatigue crack growth life of the axle using two crack growth rate models. The study found that the NASGRO equation provided more accurate predictions and can be used to determine inspection intervals for axles with fretting cracks.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Rui-Guo Yan, Wen-Jing Wang, Ping-yu Zhou, Wei Shan
Summary: This study proposes a method for predicting the transverse crack depth of axles and validates its effectiveness. The research results show the potential of crack monitoring methods in axle crack monitoring and safety monitoring, and provide an analysis method for the evolutionary pattern of axle cracks.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Reza Masoudi Nejad, Filippo Berto
Summary: The fatigue behavior of railway wheel specimens subjected to cyclic loading is investigated using experimental tests and numerical analysis in this paper. The results suggest that the fatigue life of specimens decreases with any increase in load level.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Materials Science, Characterization & Testing
Tadej Kocjan, Marko Nagode, Jernej Klemenc, Simon Oman
Summary: Rubber fatigue crack growth tests are a faster and less expensive method for characterizing fatigue behavior compared to fatigue crack initiation tests. This study investigated the possibility of using a new specimen grip geometry for crack growth tests and evaluated different variations of crack growth predictor parameters and crack growth angles. The results showed that the simplified crack growth predictor provided similar results to tearing energy, and using the Euclidean length of crack growth increments yielded better results than their horizontal projection.
Article
Mechanics
Yanan Hu, Shengchuan Wu, Philip J. Withers, Huatang Cao, Pei Chen, Yajun Zhang, Zhao Shen, Tomas Vojtek, Pavel Hutar
Summary: The study found that railway EA4T alloy steel is very sensitive to chloride-containing environments, with cracking occurring in rotating bending tests, and scratched specimens having shorter lifetimes. The research also showed that the corrosive environment facilitates crack initiation without the need for corrosion pits.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Chemistry, Multidisciplinary
Christoph Tuschl, Beate Oswald-Tranta, Sven Eck
Summary: Inductive thermography is an effective non-destructive testing method for detecting surface cracks using short heating pulses and an infrared camera. It is particularly useful for detecting head checks and squats on railway rails, as well as characterizing crack networks. Various techniques, including 'stop-and-go' and continuous scanning, are compared to optimize rail inspection processes.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Mechanical
Z. Tian, H. Yin, Z. Zhao, Y. Meng
Summary: In this study, rotating bending fatigue tests were conducted on EA4T steel at different temperatures to investigate its fatigue strength. It was found that the fatigue strength increases with the drop of temperature, except at -120 degrees C. The mechanism of low temperature strengthening was explained by considering the effect of temperature on flow stress and stress distribution.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Han Zhang, Shengchuan Wu, Ni Ao, Jiwang Zhang, Hang Li, Liang Zhou, Pingguang Xu, Yuhua Su
Summary: This study investigates the behavior of fatigue cracks in railway axles and reveals the significant role of gradient microstructure and residual stress in enhancing fatigue cracking resistance.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Automation & Control Systems
Lawal Umar Daura, Gui Yun Tian
Summary: This study aims to characterize inclined angular rolling contact fatigue (RCF) crack parameters in rail-line material using a modified topology of Wireless Power Transfer (WPT)-based Eddy Current Testing (ECT) (WPTECT). The WPTECT shows higher sensitivity to RCF cracks and utilizes multiple resonance responses for crack characterization. Experimental results demonstrate that the extracted features from WPTECT can accurately quantify the depth, opening width, and angle of RCF cracks.
IEEE TRANSACTIONS ON INDUSTRIAL INFORMATICS
(2023)
Article
Engineering, Mechanical
Renan L. Ribeiro, Michael R. Hill
Summary: This paper assesses the accuracy of fatigue crack growth predictions for high-strength aluminum samples with residual stress and complex two-dimensional cracks under constant amplitude load. The predictions use linear-elastic, multi-point fracture mechanics. The experimental data show a significant influence of residual stress, and considering the residual stress improves the accuracy of crack growth predictions.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Monika Duda, Dariusz Rozumek, Michal Smolnicki, Anna Wybraniec
Summary: The article discusses the results of a study on fatigue fracture in mixed and I + II and I + III modes in heat treated steel 42CrMo4. It presents different mechanical properties resulting from various thermal treatments and demonstrates tests conducted on different sample types and load angles. The research aims to enhance understanding of fatigue crack development under mixed modes and provide valuable insights into the material's behavior under complex loads.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Construction & Building Technology
Fengjun Lv, Wanzhen Wang, Wei Zhao
Summary: In this study, 20 fatigue tests were conducted on notched plates of Q460C steel to examine the effects of relative stress amplitude, Delta sigma/f(y), and relative nominal maximum stress, sigma(max)/f(y), on the fatigue life of these notched plates. Theoretical analyses and numerical simulations based on an ellipsoidal fracture model were used to investigate fatigue cracking in the Q460C steel notched plates. The unified crack growth approach was further developed to estimate the fatigue life of the Q460C steel notched plates, and its accuracy was assessed compared to the recommended fatigue life formula in China's code GB50017-2017. The results indicate that the unified crack growth approach provides a reliable assessment of fatigue life for the Q460C steel notched plates.
Article
Engineering, Mechanical
Hang Li, Jiwang Zhang, Shengchuan Wu, Haonan Zhang, Yanan Fu
Summary: This study investigated the effect of corrosion on the fatigue behavior of EA4T axle steel in an artificial rainwater environment, revealing that the corrosive environment significantly reduced fatigue strength and facilitated multiple crack initiation, while showing relatively little effect on the long fatigue crack growth.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Aref Mehditabar, Saeid Ansari Sadrabadi, Raffaele Sepe, Enrico Armentani, Jason Walker, Roberto Citarella
APPLIED SCIENCES-BASEL
(2020)
Article
Chemistry, Multidisciplinary
Enrico Armentani, Alessandro Greco, Alessandro De Luca, Raffaele Sepe
APPLIED SCIENCES-BASEL
(2020)
Article
Engineering, Mechanical
R. Sepe, S. Franchitti, R. Borrelli, F. Di Caprio, E. Armentani, F. Caputo
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2020)
Article
Engineering, Mechanical
Raffaele Sepe, Alessandro De Luca, Alessandro Greco, Enrico Armentani
Summary: This paper presents a novel numerical model based on the finite element method for simulating residual stresses and distortions in a welding process, using the 'element birth and death' technique for weld filler supply simulation. Advancements include simulating plate interaction and using a more efficient method for supplying heat to FEs.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2021)
Article
Chemistry, Multidisciplinary
Venanzio Giannella, Raffaele Sepe, Roberto Citarella, Enrico Armentani
Summary: Three different finite element method modelling approaches for bolt connections in a four-stroke, four-cylinder petrol engine were compared in terms of preprocessing time and accuracy. While full 3D modelling showed high accuracy, a 1D approach was generally recommended due to its pros outweighing the cons in most cases.
APPLIED SCIENCES-BASEL
(2021)
Article
Materials Science, Multidisciplinary
Raffaele Sepe, Venanzio Giannella, Alessandro Greco, Alessandro De Luca
Summary: This study investigated the welding process of a dissimilar T-joint using advanced Finite Element modeling and experimental testing. Through comparing numerical and experimental results, it was found that the FE model showed a high level of accuracy in predicting temperature distributions and distortions during the welding process.
Article
Engineering, Mechanical
Giovanni Meneghetti, Alberto Campagnolo, Alberto Visentin, Massimiliano Avalle, Matteo Benedetti, Andrea Bighelli, Davide Castagnetti, Andrea Chiocca, Luca Collini, Massimiliano De Agostinis, Alessandro De Luca, Eugenio Dragoni, Stefano Fini, Vigilio Fontanari, Francesco Frendo, Alessandro Greco, Giuseppe Marannano, Fabrizio Moroni, Antonio Pantano, Alessandro Pirondi, Alessandro Rebora, Alessandro Scattina, Raffaele Sepe, Andrea Spaggiari, Bernardo Zuccarello
Summary: This paper presents a Round Robin study among eleven Italian Universities to calibrate the peak stress method (PSM) using seven different commercial FE software packages. The study found that most of the FE software packages had similar PSM parameter values, with the main source of discrepancy being the stress extrapolation method at FE nodes.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Materials Science, Multidisciplinary
Venanzio Giannella, Giovanni Baglivo, Rosario Giordano, Raffaele Sepe, Roberto Citarella
Summary: This paper presents a structural analysis of an innovative testing facility for small aircraft landing gear, validating the design and assessing its reliability.
Article
Automation & Control Systems
Raffaele Sepe, Alessandro De Luca, Venanzio Giannella, Rosario Borrelli, Stefania Franchitti, Francesco Di Caprio, Francesco Caputo
Summary: This paper experimentally investigates the influence of dimension, building position, and orientation on the mechanical properties of Ti6Al4V trusses. The results show that truss diameter, specimen position, and orientation have an impact on the mechanical properties. Trusses with a diameter of 2 mm manufactured at 45 degrees demonstrate the best performance, while trusses with a diameter of 2 mm manufactured at 90 degrees display the highest elongation at fracture.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2022)
Article
Engineering, Mechanical
R. Sepe, V. Giannella, N. Razavi, F. Berto
Summary: This study investigates the mechanical properties of the aluminium lithium alloy Al-Li 2198-T851 in both longitudinal and transversal rolling directions. It is found that the material exhibits enhanced mechanical properties compared to 2024-T3 in both directions, but the transversal direction shows significantly lower performances.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Materials Science, Multidisciplinary
Flavia Bollino, Venanzio Giannella, Enrico Armentani, Raffaele Sepe
Summary: Natural Fibers Reinforced Composites (NFRC) are lightweight, easy to handle, process, and recycle, making them attractive alternatives to glass or carbon composites. However, their polarity causes compatibility issues with hydrophobic thermoplastic matrices, leading to moisture absorption and debonding between fibers and matrix, affecting the mechanical properties. Chemically treated hemp fibers were used to manufacture NFRCs and were tested for moisture absorption and tensile strength based on different treatments, temperatures, and concentrations of reagents. The results showed that treatments with 5 wt% NaOH and GPTMS were the most effective in reducing water uptake and stiffness decrease in the composites. The specimen treated with 5 wt% GPTMS was particularly effective in preventing composite failure induced by water uptake.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Proceedings Paper
Engineering, Mechanical
Raffaele Sepe, Venanzio Giannella, Vittorio Alfieri, Fabrizia Caiazzo
Summary: The industry demands advanced materials with high strength, fatigue resistance, and lightweight properties. Additive Manufacturing technologies allow for fabrication of lightweight components without the need for welding operations. This study evaluates the potential use of laser welding to join AM parts and overcome the limitation of producing small parts. The experimental campaign on laser-welded AM specimens shows promising fatigue performance and further developments are in progress.
SECOND EUROPEAN CONFERENCE ON THE STRUCTURAL INTEGRITY OF ADDITIVELY MANUFACTURED MATERIALS
(2021)
Proceedings Paper
Engineering, Mechanical
R. Sepe, F. Bollino, F. Caiazzo, F. Berto
Summary: This paper investigated the susceptibility to stress corrosion cracking (SCC) of high-strength steel structures in marine environments through SSRT tests, finding that both seawater corrosion and acid-polluted marine atmospheres can impact its corrosion resistance.
49TH ITALIAN ASSOCIATION FOR STRESS ANALYSIS CONFERENCE (AIAS 2020)
(2021)
Proceedings Paper
Engineering, Mechanical
V Giannella, R. Sepe, G. De Michele, R. Esposito
Summary: The study focused on the crack propagation of railway axles and its influence on NDT inspection intervals, providing specific conclusions through calculations and simulations, leading to estimates of residual fatigue life.
49TH ITALIAN ASSOCIATION FOR STRESS ANALYSIS CONFERENCE (AIAS 2020)
(2021)
Article
Engineering, Mechanical
Willy Ank de Morais, Railson Bolsoni Falcao, Mario Boccalini Jr, Fernando Jose Gomes Landgraf
Summary: This study compares the fatigue behavior of bcc Nb-48 wt%Ti (Ti-36at%Nb) alloy parts processed by Laser Powder Bed Fusion (L-PBF) using two different types of powders (spherical powder produced by Plasma Atomization and irregularly shaped powder produced by Hydride-Dehydride). The results show that the fatigue behavior is similar for both powders, but the specimens produced from the Hydride-Dehydride powder have higher dispersed results. Fracture primarily occurs in the porosities near the machined sample surface, and the fatigue cracks propagate in a zigzag mode parallel to the L-PBF building direction.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Guoxi Jing, Shuai Sun, Teng Ma, Shubo Li, Tian Ma, Junchao Wei, Jianchao Pang
Summary: This study proposes a parameter identification method for predicting the TMF life of CGI materials used in cylinder heads. The study evaluates the TMF behavior of RuT450 material and successfully predicts its TMF life using multi-objective optimization. The results highlight the influence of plastic strain amplitude, temperature, and strain rate on the damage mechanism and life prediction.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Xin Zhang, Xu Li, Weipeng Xu, Kuidong Gao, Kao Jiang, Xinyu Wang, Hongxin Wei
Summary: Conical picks are commonly used in tunnel excavation and often experience high temperatures during the cutting process. This study investigated the influence of temperature on the wear of conical picks and proposed a method for measuring rock abrasiveness that takes into account the thermal effect. The experimental results showed that cooling liquid reduced the maximum temperature and the mean mass loss of the conical pick. Additionally, the study examined the characteristics of oxygen and found evidence of peeling, cracking, and oxidation on the grinding rod used for rock abrasiveness measurement.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Vivek Srivastava, Deependra Singh, A. G. Rao, V. P. Deshmukh
Summary: Engine gear failures are a significant concern in various industries. Investigating each gear failure and determining the root cause is important for preventing future failures. This study used experimental and numerical analysis techniques to investigate the premature failure of a flywheel gear in a marine diesel engine. The findings revealed that the gear failed due to overload stresses caused by overload torque generated from sudden inertial thrust in the internal combustionengine.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Jun Zhang, Weidong Liu, Feilong Liu, Zhiqiang Yang, Jinfang Peng, Minhao Zhu
Summary: During a major overhaul of an aeroengine, a cracked stator vane of the low-pressure compressor was discovered, with the crack originating from a corrosion pit located on the arc transition between the leading edge and the upper edge plate. The fracture surface exhibited signs of fatigue cracks, indicating a pit-related fatigue crack. Metallographic examination revealed that most corrosion pits were distributed beneath the bulging or peeling paint layer on the leading edge and the concave side. Identification of the corrosion products showed the presence of sulfate and alumina, suggesting atmospheric corrosion as a likely cause for the cracked stator vane.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Juan Jose Jimenez de Cisneros Fonfria, Ester Olmeda, Susana Sanz, Maria Garrosa, Vicente Diaz
Summary: Energy absorbing devices in vehicles can partially transform impact energy and protect passengers. In this paper, the failure analysis of the underframe crumple zone in a train car was conducted through finite element simulations, showing that the component acted properly after the impact.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Fengqi Zhang, Gang Luo, Haiyang Zhang, Peihong Cong, Lulu Liu, Wei Chen
Summary: In this study, a predictive model for bird strike trajectory was developed based on the quasi-linear viscoelastic model. By combining simulation analysis under multiple conditions, the model reproduced the trajectory change law in low and medium speed bird impact experiments.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
S. M. de Gouveia, L. de Abreu Correa, D. B. Teles, M. Oliveira, T. G. R. Clarke
Summary: Emergency Shutdown Valves (EDSVs) are used in industrial applications to interrupt fluid flow during hazardous events. The damage to the valve seats can be detected by analyzing the pressure and torque data. This study compared three processing options and found that evaluating the complete signature with a Gradient Boosting Classifier algorithm is the most effective strategy.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Xinyan Jin, Kai Wang, Hongwei Qian
Summary: This study investigated the root cause of an abnormal premature groove-clogging failure on a sink roll in a hot-dip galvanizing line. It was found that the failure was caused by the buildup of a large amount of Fe2Al5Znx dross in the grooves, and the key factor was the control of Tstrip.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Zhiqiang Li, Jie Li, Cen Li, Xiaodong Xie, Zhiyong Yang
Summary: In this study, the microstructure evolution of the material in the hot spot area of the high-speed train brake disc was observed and the mechanism of mechanical property degradation was obtained through tensile tests. The research results provide guidance for crack damage identification of the brake disc and condition-based maintenance.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Lijia Luo, Yincheng Wang, Wei Chen, Zuming Zhao, Wenfei Chen, Shiyi Bao
Summary: Tube-to-tube impact wear is a significant factor in the failure of alloy 690 tubes in nuclear steam generators. This paper investigates the wear damage mechanism and detection method of alloy 690 tubes under tube-to-tube impact loads. The results reveal the wear damage mechanism through analysis of macro and micro morphologies as well as metallographic structures. A nonlinear ultrasonic wave mixing method is proposed for damage detection and a detection device is developed to implement this method. Experimental results indicate that the damage mode of tube-to-tube impact wear varies with impact load and cycle number, and the nonlinear modulation index is effective in assessing the damage degree of alloy 690 tubes.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Xing-Ju Yang, Feng Lin, Xu Du, Lu Qiu
Summary: This paper proposes a novel method of improving the progressive collapse resistance of RC frame structures by adding locally debonded kinked steel plates (KPs). Experimental tests and finite element analysis reveal that the addition of KPs significantly enhances the ultimate resistance and deformability of the beam-slab substructures. The mechanism of resistance improvement is explained, and an analytical model is developed for predicting the ultimate resistance of the structures.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Xiaohe Wang, Zengqiang Cao
Summary: This paper presents a dynamic installation (DI) method based on electromagnetic force to reduce damage to composite laminates and improve joint performance. The study shows that DI can effectively decrease installation resistance, reduce severe damage to laminates, and improve stress distribution in the joint.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Jitong Cui, Yingying Kong, Cuiwei Liu, Baoping Cai, Faisal Khan, Yuxing Li
Summary: This paper presents a method for quantifying the failure probability of hydrogen doped pipelines and utilizes Bayesian network for quantitative calculation. The results show that this method can more accurately assess the failure probability of hydrogen doped pipelines and provide a decision basis for preventing failure accidents.
ENGINEERING FAILURE ANALYSIS
(2024)
Article
Engineering, Mechanical
Yiping Jiang, Maoru Chi, Jungang Yang, Liangcheng Dai, Yuchen Xie, Zhaotuan Guo
Summary: This article investigates and simulates the derailment of empty freight trains at the switch section of a turnout in the diverging route, and proposes preventive measures. The results show that the derailment is caused by the combined effect of various factors, and reducing the longitudinal coupler force and the wheel rail friction coefficient can decrease the possibility of derailment. Additionally, installing a guard rail in front of the turnout can effectively prevent derailment.
ENGINEERING FAILURE ANALYSIS
(2024)