Article
Chemistry, Physical
Michael Fitzka, Bernd M. Schoenbauer, Robert K. Rhein, Niloofar Sanaei, Shahab Zekriardehani, Srinivasan Arjun Tekalur, Jason W. Carroll, Herwig Mayer
Summary: This study summarizes the comparability of fatigue properties measured with ultrasonic and conventional equipment, focusing on the performance of different materials at ultrasonic frequencies. Aluminium alloys and high-strength steels are insensitive to cycling frequency, while the strain rate sensitivity of ferrite may lead to prolonged lifetimes.
Article
Engineering, Mechanical
Ming-Liang Zhu, Gang Zhu, Fu-Zhen Xuan
Summary: This study explores the mechanism of the formation of fine granular area morphology in the case of very high cycle fatigue failure of high strength steel. It proposes a microstructure-dependent crack initiation and early growth model based on the fragmentation of martensitic laths and formation of dislocation cells. The model has been verified under environmental fatigue and found applicable to white etching crack in rotating contact fatigue. Additionally, a machine learning-Z parameter integrated approach for fatigue life prediction has been developed, showing promise for designing engineering structures with long life.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Yujia Liu, Bo Xu, Sen Tang, Lang Li, Chao He, Chong Wang, Qingyuan Wang
Summary: This paper presents a thermodynamic characterization method for estimating the internal crack growth rate in very high cycle fatigue research. It discusses a theoretical approach for surface temperature considering crack size, initiation site, and time for thin sheet material. Infrared thermography is used to study the inner crack behavior and heat dissipation phenomenon on high-strength stainless steel under 20 kHz vibration loading. A numerical simulation reveals the temperature elevation on surfaces caused by heat generation at the crack tip and heat conduction. Ultimately, the internal crack growth rate and final fatigue failure prediction are obtained by combining the calculation of heat dissipation and the observed evolution of the surface temperature field.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Jia-Le Fan, Gang Zhu, Ming-Liang Zhu, Fu-Zhen Xuan
Summary: This study combines physical parameters with artificial neural networks to predict the fatigue life of 15Cr and FV520B-I steels. The results show that this approach has higher predictive accuracy compared to traditional physical parameter models and the Mayer model.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Nanoscience & Nanotechnology
Xiaolu Gui, Guhui Gao, Baifeng An, R. D. K. Misra, Bingzhe Bai
Summary: The study investigated the effects of inclusion size and microstructural features on HCF/VHCF in a B/M steel. It was found that fatigue crack initiation was mainly influenced by inclusions, with the majority of fatigue life consumed by the crack initiation process regardless of the source of the crack. The ratio of fatigue crack initiation life to total fatigue life exhibited a wide scatter due to variations in the B/M hierarchical structure within individual prior austenite grains when cracks initiated from sub-surface microstructure.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Engineering, Mechanical
Stephanie Saalfeld, Marcel Krochmal, Thomas Wegener, Berthold Scholtes, Thomas Niendorf
Summary: VCHF tests on SAE 1045 steel under different deep rolled conditions revealed that the dominant failure mode is related to internal material defects causing fisheye fracture appearance. The stable tensile residual stresses in the core of high-temperature deep rolled specimens promoted crack initiation and advance, ultimately resulting in inferior fatigue strength.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Engineering, Mechanical
Lang Zou, Liantao Lu, Yabo Li, Kai Yang, Hai Zhao, Yihui Dong, Dongfang Zeng
Summary: In this study, fretting fatigue experiments for scaled railway axles were extended from the high cycle (HC) regime to the very high cycle (VHC) regime. The experimental investigation found that the fretting fatigue strength of railway axles in the VHC regime decreased with an increase in the number of test cycles. The developed evaluation method in the numerical study can provide a reasonable estimation of the occurrence of fretting crack initiation in the VHC regime.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Mechanics
Yu-Ke Liu, Jia-Le Fan, Gang Zhu, Ming -Liang Zhu, Fu -Zhen Xuan
Summary: Research on life prediction for mechanical structures in very high cycle fatigue regime is crucial, but collecting fatigue data can be expensive and time-consuming. To address this, machine learning's data-driven approach has emerged as a solution. In this study, a small dataset of GCr15 bearing steel subjected to very high cycle fatigue tests was extracted, and the Z-parameter model was used to generate extended datasets. Models driven by support vector machine, artificial neural network, and Z-parameter based physics-informed neural network were established. The physics-informed neural network calibrated by Z-parameter model trained on a larger dataset demonstrated more accurate and reliable prediction compared to other models. The effectiveness of Z-parameter in data extension and model construction as priori physics knowledge for a data-driven approach was shown. In the future, the Z-parameter model deserves more attention in life prediction for engineering materials and structures in the very high cycle fatigue regime.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Nanoscience & Nanotechnology
Alice Cervellon, Chris J. Torbet, Tresa M. Pollock
Summary: The anisotropic fatigue properties of three Ni-based SX superalloys were investigated in the very high cycle fatigue regime. The [111] orientation showed higher fatigue lives at high stresses but lower fatigue lives at very low stresses. The resolved shear stress on the octahedral slip systems and the pseudo-cube slip in the matrix were identified as the main reasons for the anisotropy effect.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Mechanics
Han Wu, Chengqi Sun, Wei Xu, Xin Chen, Xiaolei Wu
Summary: In this paper, a continuous runout method (CRM) is proposed to evaluate the fatigue strength in high cycle and very high cycle fatigue regimes based on the probability and statistics theory. The CRM features the simultaneous testing of multiple samples, which reduces the testing period to 1/5-1/3 of that by the common up-and-down method for 16 samples. Experimental data for G20Mn5QT steel, 40 Cr steel, and Ti-6Al-4V alloy validate the CRM's predicted lower limits of fatigue strength, which are slightly more conservative than those obtained by the up-and-down method.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Materials Science, Multidisciplinary
Zhi Qin, Bin Li, Chen Chen, Tianyue Chen, Rui Chen, Han Zhang, Hongqian Xue, Changfeng Yao, Liang Tan
Summary: The study investigated the high cycle and very high cycle fatigue behavior of the GH4169 superalloy. The results showed that failures in different fatigue regimes had different initiations, and significant strain localization occurred at the twin boundaries of the material under fatigue cyclic loading.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Chemistry, Physical
Ruixiang He, Haotian Peng, Fulin Liu, Muhammad Kashif Khan, Yao Chen, Chao He, Chong Wang, Qingyuan Wang, Yongjie Liu
Summary: Ultrasonic fatigue tests were conducted on Ti60 titanium alloy in the very high cycle fatigue regime, revealing continuous declining trends in the S-N curves and fatigue limits at different stress ratios. Fatigue cracks in the VHCF regime were found to initiate from the subsurface, particularly at high stress ratios. Two modified fatigue life prediction models based on fatigue crack initiation mechanisms for the Ti60 titanium alloy in the VHCF regime were developed and showed good agreement with experimental data.
Article
Engineering, Mechanical
Jie Wan, Jiucheng Zhao, Liming Zhou, Shizhong Zhang, Hongwei Zhao
Summary: In this study, a new cantilever specimen and methodology based on the Timoshenko beam theory and the transfer matrix method were proposed for bending ultrasonic fatigue testing in the VHCF regime. The results of Finite Element Analysis and experimental results from Ti-6Al-4V specimens demonstrate the feasibility and applicability of this methodology for deep research on the bending fatigue behaviors of rotor blade materials.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Weiqian Chi, Wenjing Wang, Ying Li, Wei Xu, Chengqi Sun
Summary: This paper investigates the effect of defect location and introduced form on fatigue performance in selective laser melting Ti-6Al-4V alloys. It is found that internal defects lead to a linear decrease in fatigue strength, while artificial surface defects initially decrease and then exhibit a plateau region feature. Competition between interior crack initiation and fine granular area feature is also observed in very high cycle fatigue regime.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Ying Zheng, Huili Sun, Luchun Yan, Xiaolu Pang, Kewei Gao
Summary: The very high cycle fatigue behavior of precipitation hardening stainless steel (PHSS) with different aging times was investigated. The PHSS aged for 1 hour at 480 degrees C exhibited the highest fatigue strength, followed by 4 hours and 0.5 hours of aging. Both subsurface or internal inclusion-induced crack initiation (IICI) and non-inclusion-induced crack initiation (NIICI) were observed. The NIICI phenomenon was attributed to the nucleation and connection of microvoids within the delta-ferrite. Aging treatment had a significant influence on the dominant crack initiation mechanism by altering the interaction of dislocations and copper precipitates, which ultimately affected the fatigue performance.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Acoustics
Philipp Neubauer, Johannes Tschesche, Joachim Boes, Tobias Melz, Holger Hanselka
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2018)
Article
Engineering, Mechanical
Christopher M. Gehb, Roland Platz, Tobias Melz
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2019)
Article
Materials Science, Multidisciplinary
Daniel Loos, Endre Barti, Gunter Schroeter, Rainer Wagener, Tobias Melz
JOURNAL OF MATERIALS SCIENCE
(2019)
Article
Engineering, Mechanical
C. M. Gehb, S. Atamturktur, R. Platz, T. Melz
EXPERIMENTAL TECHNIQUES
(2020)
Article
Materials Science, Characterization & Testing
Daniel Loos, Endre Barti, Rainer Wagener, Tobias Melz
Article
Engineering, Mechanical
M. B. Geilen, M. Klein, M. Oechsner, M. Kaffenberger, K. Stoerzel, T. Melz
INTERNATIONAL JOURNAL OF FATIGUE
(2020)
Article
Acoustics
Philipp Neubauer, Joachim Boes, Tobias Melz
JOURNAL OF SOUND AND VIBRATION
(2020)
Article
Nanoscience & Nanotechnology
A. Gramlich, T. Schmiedl, S. Schoenborn, T. Melz, W. Bleck
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2020)
Article
Metallurgy & Metallurgical Engineering
Tobias Schmiedl, Alexander R. M. Gramlich, Steffen Schoenborn, Tobias Melz
STEEL RESEARCH INTERNATIONAL
(2020)
Article
Chemistry, Multidisciplinary
Yaxiong Ren, Christian Adams, Tobias Melz
Summary: This study developed a system identification procedure based on the Sparse Identification of Nonlinear Dynamical Systems (SINDy) method and validated it on a single-mass oscillator. Two sparse regression methods were compared for parameter estimation, and the Least Squares method Post-LASSO (LSPL) showed better performance. The developed SINDy-LSPL method was successfully implemented with real measurement data and found to be more accurate when using a sweep signal as excitation compared to impulse excitation.
APPLIED SCIENCES-BASEL
(2022)
Proceedings Paper
Materials Science, Multidisciplinary
Matthias Hell, Rainer Wagener, Tobias Melz
TMS 2020 149TH ANNUAL MEETING & EXHIBITION SUPPLEMENTAL PROCEEDINGS
(2020)
Article
Engineering, Mechanical
Benjamin Moeller, Kai Schnabel, Rainer Wagener, Heinz Kaufmann, Tobias Melz
INTERNATIONAL JOURNAL OF FATIGUE
(2020)
Proceedings Paper
Engineering, Mechanical
Thorsten Voigt, Klaus Lipp, Tobias Melz
FATIGUE DESIGN 2019, INTERNATIONAL CONFERENCE ON FATIGUE DESIGN, 8TH EDITION
(2019)
Proceedings Paper
Engineering, Mechanical
Rainer Wagener, Matilde Scurria, Heinz Kaufmann, Tobias Melz
FATIGUE DESIGN 2019, INTERNATIONAL CONFERENCE ON FATIGUE DESIGN, 8TH EDITION
(2019)
Proceedings Paper
Construction & Building Technology
Benjamin Moeller, Simon Albrecht, Rainer Wagener, Tobias Melz
25TH INTERNATIONAL CONFERENCE ON FRACTURE AND STRUCTURAL INTEGRITY
(2019)
