Article
Engineering, Mechanical
Tianyu Zhang, Xiaowei Wang, Xianxi Xia, Yong Jiang, Xiancheng Zhang, Liguo Zhao, Anish Roy, Jianming Gong, Shantung Tu
Summary: This paper develops a robust creep-fatigue interaction (CFI) life prediction model, which considers the effect of creep strain and demonstrates its broad applicability for various materials and loading conditions.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Mechanics
Zhanming Shi, Jiangteng Li, Ju Wang
Summary: This study investigates the effect of creep loading on the fracture mode and damage evolution process of jointed rock masses during fatigue loading. The results show that applying creep load during fatigue loading can change the fracture mode, improve shear resistance, and increase brittleness. Additionally, creep load can reduce the rate of damage growth and increase the fatigue life of the rock mass.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Adam Tomczyk, Andrzej Seweryn
Summary: This article presents the experimental tests of creep rupture and low-cycle fatigue of EN-AW 2024 aluminum alloy. The tests were conducted with and without preliminary damage at different temperatures. A simple damage accumulation model was proposed based on the experimental results to describe the damage accumulation in both creep and low-cycle fatigue.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Mechanics
Tianyu Zhang, Xiaowei Wang, Chunan Zhang, Yong Jiang, Jianfeng Wen, Xiancheng Zhang, Jianming Gong
Summary: Hybrid stress-strain controlled creep-fatigue interaction (HCFI) tests were conducted on 9% Cr steel with strain amplitudes ranging from ±0.25% to ±0.6%. Increase in strain amplitude leads to increased possibility of cracking and reduced crack deflections, along with differences in LABs and grain size. However, for HCFI tests with high creep damage, strain amplitude plays a minor role as significant creep strain during stress holding is converted into fatigue strain even at low strain amplitudes. Moreover, a dwell indicator (DI) benchmarked against macroscopic LCF responses is proposed to evaluate strain amplitude-induced microscopic HCFI damage. Significant changes in internal degradation and fracture behaviors occur when DI is approximately equal to (or greater than) 0.9, while HCFI damage shows low sensitivity to strain amplitude when DI is close to (or lower than) 0.5.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
Kai Song, Dong Wang, Lei Zhao, Lianyong Xu, Yongdian Han
Summary: The creep-fatigue behavior of 9Cr3Co3W1CuVNbB steel under strain-controlled and hybrid stress-strain controlled conditions is studied. An improved method for predicting creep-fatigue life is proposed, which accurately predicts the relaxed stress and accumulated creep strain of the material. The influence of oxidation damage on nonlinear interactions is also considered.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
W. Macek, A. Tomczyk, R. Branco, M. Dobrzynski, A. Seweryn
Summary: This paper explores the applicability of a new damage parameter that combines fracture surface topography and loading features to estimate fatigue lifetime under creep pre-strain and low-cycle fatigue loading. Through surface topography analysis, the fractures of EN-AW 2024 aluminum alloy caused by mixed creep and low-cycle fatigue loading are experimentally characterized and quantified. The study proposes and verifies an original fatigue life prediction model based on both surface topography values and applied strains. The proposed model is helpful for post-mortem analysis of engineering components subjected to fatigue loading accounting for creep pre-strain.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Tianyu Zhang, Xiaowei Wang, Yunnan Ji, Jianqun Tang, Yong Jiang, Xiancheng Zhang, Jianming Gong
Summary: The results of HCFI tests on 9%Cr steel at 625 degrees C reveal that conservative dwell conditions lead to complex cyclic responses and low creep strain, ultimately resulting in strong creep-fatigue interaction damage.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Materials Science, Multidisciplinary
Yuxuan Song, Zhouxin Pan, Yuebing Li, Weiya Jin, Zengliang Gao, Zhenggang Wu, Yi Ma
Summary: The effect of temperature on the creep-fatigue fracture behavior of 316H austenitic stainless steel was studied using nanoindentation technique. A structural damage indicator was proposed to characterize the damage of grain boundaries, unveiling the relationship between fracture mechanism and temperature.
MATERIALS CHARACTERIZATION
(2022)
Article
Engineering, Mechanical
Zhanming Shi, Jiangteng Li, Ju Wang
Summary: In this study, the effects of creep loading on the fatigue behavior and acoustic emission characteristics of jointed rock masses during fatigue loading were investigated. The results showed that the application of short-term, low-stress creep load can effectively control the growth rate of damage, reduce deformation parameters, and increase the fatigue life of the rock mass.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Nanoscience & Nanotechnology
Yuxuan Song, Yi Ma, Haofeng Chen, Zhibo He, Hu Chen, Taihua Zhang, Zengliang Gao
Summary: This study investigated the creep-fatigue interactions on the long-term service damage of P92 welded joint by conducting tensile and compressive tests under different applied strains. Using nanoindentation, the local mechanical properties of the welded joint were examined, while scanning electron microscope was used to analyze fracture morphologies and internal defects after CF tests, revealing the effects of holding type on the local creep behavior and fracture mechanism of the welds.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Chemistry, Physical
Stanislaw Mrozinski, Zbigniew Lis, Halina Egner
Summary: This paper presents the results of tests on P91 steel samples under the conditions of simultaneous fatigue and creep. The study shows that creep significantly reduces the durability of the samples. It also suggests that considering the influence of creep in the linear fatigue damage summation approach can improve the accuracy of fatigue life predictions.
Article
Nanoscience & Nanotechnology
K. Mariappan, A. Nagesha
Summary: The paper presents a study on the creep-fatigue interaction behavior of simulated heat-affected zones (HAZs) of P91 steel weldment with different microstructures. Strain-controlled fatigue tests were conducted at 550 C, showing continuous cyclic softening under the creep-fatigue condition. Strain localization and interlinkage of subsurface creep cavities caused enhanced crack propagation, resulting in the lowest fatigue life in the inter-critical HAZ. The actual weldment failed in the interface between fine grain HAZ and inter-critical HAZ, largely governed by Type IV cracking.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Chemistry, Physical
Jie Zhang, Qiuhua Rao, Wei Yi
Summary: Studying the creep-fatigue interaction of coarse-grained soil is crucial for safety assessment and disaster prevention in subgrade engineering. This paper establishes a new model to predict the deformation caused by creep-fatigue interaction in different gradation coarse-grained soils. Experimental results confirm the validity of the new model.
Article
Materials Science, Multidisciplinary
P. Manikandan, G. Sudarshan Rao, S. V. S. Narayana Murty, V. M. J. Sharma, D. Sivakumar, P. Ramesh Narayanan, M. Mohan
Summary: The effect of uniaxial pre-strain in the range of 1-9% on the tensile and creep behavior of aluminum alloy AA2219-T87 at room temperature has been investigated in this study. The tensile properties of pre-strained specimens showed an increase in yield strength up to 3% pre-strain, but beyond this range, the ductility in terms of percentage elongation was below the specification limit of 6%. Room temperature creep test results indicated a linear relationship between applied stress, creep rate, and time to failure. The fracture toughness of AA2219-T87 decreased with increasing pre-strain, as calculated using an empirical relationship. Based on the extensive experimental results, it is recommended to limit the pre-strain to 3% during hardware fabrication to meet the material specifications.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Engineering, Mechanical
Zhi Liu, Jian-Guo Gong, Peng Zhao, Xiao-Cheng Zhang, Fu-Zhen Xuan
Summary: This study investigated the creep fatigue behavior of 9-12%Cr steel under stress-controlled cycling at elevated temperature, considering most previous tests were conducted under strain-controlled mode. The effects of holding time and loading rate on deformation and damage behavior were particularly focused. The results showed that a significant creep ratcheting was generally observed in the creep-fatigue tests with the stress ratio of -1. Ratcheting strain and creep damage progressed faster with longer holding time or lower loading rate, leading to a decrease in the number of cycles to creep-fatigue failure.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Multidisciplinary
Jianfeng Mao, Xiangyang Li, Shiyi Bao, Renyue Ge, Ling Yan
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2019)
Article
Engineering, Environmental
Bo Yang, Jianxin Zou, Tianping Huang, Jianfeng Mao, Xiaoqin Zeng, Wenjiang Ding
CHEMICAL ENGINEERING JOURNAL
(2019)
Article
Green & Sustainable Science & Technology
Di Tang, Min Xu, Jianfeng Mao, Hai Zhu
Article
Engineering, Mechanical
Shiyi Bao, Zhongyang Xiao, Xiangyang Li, Fengping Zhong, Jianfeng Mao
Summary: This study investigated the multi-axial creep behavior of Inconel 718 alloy at high temperature using experimental and numerical analysis. The influence of notch radius on creep behavior and damage evolution was studied under the influence of stress triaxiality. The finite element method (FEM) implemented by the Gurson-Tvergaard-Needleman (GTN) model successfully predicted the multi-axial creep behavior with good agreement between FEM and experimental data.
JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Materials Science, Multidisciplinary
Zhiming Lu, Fan Xu, Chong Tang, Yang Cui, Hao Xu, Jianfeng Mao
Summary: Increasing the laser energy density can enhance the surface roughness and microhardness of stainless steel, resulting in compressive residual stress and martensitic transformation. When the energy density is less than 12.74GW/cm(2), the effects of compressive residual stress and grain refinement outweigh the surface roughness, leading to a decrease in stress corrosion sensitivity index.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2021)
Article
Engineering, Mechanical
Jianfeng Mao, Jiadong Yang, Jian Zhu, Zhenyu Ding, Fengping Zhong, Dasheng Wang
Summary: This paper investigates the effect of aging on the creep-fatigue behavior of 316L steel through creep-fatigue tests before and after thermal aging. Microscopic observations reveal that aging, creep, and fatigue affect the microstructure characteristics of the steel. A creep-fatigue constitutive model is constructed and used for life prediction, and the accuracy of the model is analyzed through comparing with test data.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Shiyi Bao, Zaixiang Qin, Jian Zhu, Lijia Luo, Fengping Zhong, Jichang Chen, Jianfeng Mao
Summary: This paper addresses the issue of defects that may occur in pressure pipelines during production and service, and proposes a method of improving convergence performance by adjusting the elastic modulus. Experimental results demonstrate that this method is more efficient than traditional inelastic finite element analysis.
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2021)
Article
Engineering, Mechanical
Jianfeng Mao, Jian Zhu, Dasheng Wang, Fengping Zhong, Jichang Chen, Qiang Zhou, Shiyi Bao
Summary: In this study, P92 steel was subjected to thermal aging treatment and tested for mechanical and creep-fatigue properties. The results show that the aging treatment did not significantly affect the creep-fatigue response of the steel. Microscopic observation revealed that the aged steel still retained the typical lamellar martensite and prior austenite grains. Aging at 650 degrees C led to the formation of more martensite precipitates and an increase in martensite width, while decreasing the dislocation density. The presence of Laves phase on grain boundaries effectively strengthened them and improved the creep-fatigue resistance of the steel. Four creep-fatigue life models were obtained for the aging P92 steel, and the prediction results fell within a tolerance zone. The authors recommend the use of the frequency separation life model (FSL) and the strain energy density exhaustion model (SEDE) for predicting the creep-fatigue life of aging P92 steel.
JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME
(2022)
Article
Materials Science, Multidisciplinary
Jian Zhu, DaSheng Wang, ShiYi Bao, Qiang Zhou, ZaiXiang Qin, FengPing Zhong, JianFeng Mao
Summary: In-vessel retention (IVR) is a key strategy to ensure the structural integrity of RPV under severe accidents, where multiaxial creep is the main failure mode. The phase transition and grain boundary precipitation of 16MND5 steel have significant impacts on creep behaviors. Additionally, a new model incorporating the term of activation energy Q based on the Kachanov-Robotnov continuous damage model (CDM) has been developed to study the damage evolution and multiaxial creep behaviors of 16MND5 steel, showing good agreement with experimental results.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Engineering, Mechanical
Jianfeng Mao, Jian Zhu, Xiangyang Li, Dasheng Wang, Fengping Zhong, Jichang Chen
Summary: The creep-fatigue behaviors of P92 steel at high temperatures are mainly affected by temperature, leading to a significant reduction in fatigue life with increasing temperature. Additionally, the dislocation density decreases and the martensite laths become coarser as creep fatigue increases, while an increase in strain amplitude results in more secondary cracks and fatigue striation.
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2022)
Article
Nuclear Science & Technology
Anyu Liao, Jiadong Yang, Ting Jin, Pan Liu, Dasheng Wang, Jianfeng Mao
Summary: In-vessel retention is crucial in preventing core meltdown accidents in third generation nuclear power plants, and External Reactor Vessel Cooling (ERVC) is key to its success. This study focused on the boiling water reactor pressure vessel (RPV) and used finite element method (FEM) to establish a model that accounts for different types of ablation and thinning. The stress/strain response of the RPV was analyzed under core meltdown accidents and plastic and creep damage were assessed using continuum damage mechanics (CDM). The effect of internal pressure on creep and plastic rupture was also studied within a 72-hour timeframe. The results showed that increased internal pressure reduced the load-bearing capacity of the RPV, indicating the importance of considering pressure effects in these situations.
NUCLEAR ENGINEERING AND DESIGN
(2022)
Article
Transportation Science & Technology
Lechen Wang, Jianfeng Mao, Lishuai Li, Xuechun Li, Yilei Tu
Summary: In this study, a novel Bubble mechanism is proposed to accurately predict the medium-term Estimated Time of Arrival (ETA) for a Multi-Airport System (MAS). The prediction is decomposed into two stages: out-MAS and in-MAS stages, using ARIMA model and spatio-temporal features. A sequence-to-sequence prediction model is further developed to achieve multi-step-ahead predictions of in-MAS travel time using the spatio-temporal features as input.
TRANSPORTATION RESEARCH PART C-EMERGING TECHNOLOGIES
(2023)
Article
Transportation
Xiongwen Qian, Jianfeng Mao, Yuan Wang, Meng Qiu
Summary: A column generation-based framework is proposed for air traffic flow management (ATFM) incorporating a user-driven prioritization process (UDPP). Airspace Users' (AUs') preferences and priorities can be explicitly reflected in the framework. The proposed framework efficiently solves the ATFM problem considering UDPP features with often zero or small optimality gaps.
TRANSPORTMETRICA B-TRANSPORT DYNAMICS
(2023)
Article
Spectroscopy
Yan Jing-tao, Miao Li-jun, Mao Jian-feng, Shi Jin, Huang Teng-chao, Che Shuang-liang, Shu Xiao-wu
Summary: Research shows that using external phase modulation with high-power wideband noise sources can achieve wide spectral characteristics of lasers. This approach can achieve superior spectrum broadening without compromising the wavelength stability of the laser.
SPECTROSCOPY AND SPECTRAL ANALYSIS
(2022)
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)
