Article
Mechanics
Sandra Baltic, Werner Daves
Summary: This article investigates the development mechanism of the common squat-form crack in the railway track. It is found that the crack initiation occurs in the transverse plane and then expands into a typical squat shape in the longitudinal direction. The study also explores various factors that may trigger squat formation and analyzes the driving force and direction of crack growth using configurational force theory.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Steven J. Lorenz, Farshid Sadeghi
Summary: This study presents an investigation into the rolling contact fatigue performance of AISI M50 bearing steel under a range of Hertzian contact pressures. Both experimental and analytical approaches were used to establish the relationship between contact pressure and fatigue life. The results show good agreement between the experimental and analytical data sets, highlighting the significance of combining experimental tools and computational models in assessing the RCF performance of bearing materials.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Chemistry, Physical
Ravit Ohana, Renata Klein, Roni Shneck, Jacob Bortman
Summary: The aim of this study was to investigate the spall propagation mechanism in ball bearing raceways using physics-based models. The research developed a prognostic tool for ball bearings by understanding the spall progression process and formulating a constitutive law of spall deterioration. The study integrated a dynamic model with a finite element one to simulate the spall propagation process and used a continuum damage mechanics (CDM) approach and fracture mechanics tools to simulate the damage propagation. The simulation results were supported by experimental results from both laboratory experimental bearings and an in-service helicopter bearing.
Article
Engineering, Mechanical
Steven J. Lorenz, Farshid Sadeghi, Hitesh K. Trivedi, Mathew S. Kirsch
Summary: This study evaluated the performance of common aerospace-quality bearing steels in rolling contact fatigue through experimental and analytical methods. Three types of aerospace-quality bearing steels were procured and evaluated. The evaluation was conducted using a 3 ball-on-rod rolling contact fatigue test rig and a torsion fatigue test rig. The results provided insights into the material's strength and performance in different fatigue conditions.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Steven J. Lorenz, Farshid Sadeghi, Akshat Sharma, Chinpei Wang, Ben Wang
Summary: This work presents an improved probabilistic continuum damage mechanics (CDM) finite element (FE) model to estimate rolling contact fatigue (RCF) life of critical tribological components. The model considers multiple failure criteria and describes critical damage material parameters using a distribution. Forty unique material microstructure models were created to capture the random pathways for crack growth. The results demonstrate that the Fatemi-Socie and shear stress reversal failure criteria compared favorably to Lundberg-Palmgren theory.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Guillermo E. Morales-Espejel, Armando Felix Quinonez
Summary: The paper presents a stress-based model for predicting the life of rolling/sliding contacts in machine elements, considering surface and subsurface survival. The model requires input of the contact stress distribution and lubrication quality. It is illustrated using the example of spur gears and shows the ability to predict gear endurance and the contribution of the surface. This approach is advantageous for future gear design and applicable to rolling bearings and cam-follower systems.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Steven J. Lorenz, Farshid Sadeghi, Hitesh K. Trivedi, Lewis Rosado, Mathew S. Kirsch, Chinpei Wang
Summary: A finite element model was developed to investigate the influence of near surface orthogonal shear stress on the competitive failure mechanism between surface originated pitting and subsurface originated spalling. The results indicate that roughness frequency and half contact width are the main parameters controlling the probability of surface failure, with low frequency surfaces more susceptible to surface failure.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Steven J. Lorenz, Farshid Sadeghi, Chinpei Wang
Summary: This investigation examines the effect of various spatial hardness gradients on rolling contact fatigue life. The results show that polynomial gradients with degree greater than 1 outperform linear and polynomial gradients with degree less than 1, particularly at shallower gradient depths. Additionally, increasing gradient depth and increasing compressive residual stress improve the resistance to rolling contact fatigue.
TRIBOLOGY INTERNATIONAL
(2022)
Article
Mechanics
Thairon Reis, Allan Patrick Cordeiro Dias, Auteliano Antunes Santos
Summary: This paper proposes a new method to estimate the multiaxial non-proportional elastic-plastic stress and strain time histories developed in rails due to rolling contact, and evaluates its accuracy for fatigue analysis. The method allows for the fast determination of elastic-plastic stress and strain histories, and enables material parameter and load case studies.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Engineering, Mechanical
Steven J. Lorenz, Farshid Sadeghi, Hitesh K. Trivedi, Lewis Rosado, Mathew S. Kirsch, Chinpei Wang
Summary: In this study, a CDM FE model was developed to investigate the effects of surface roughness on RCF life, using optical surface profilometer to measure roughness of deep groove bearings. The results showed that as roughness amplitude increases or lambda ratio decreases, fatigue lives decrease for various frequencies. Subsurface failure fatigue lives are reduced with increasing roughness frequency, regardless of amplitude or Hertzian pressure. The investigation results were used to develop surface roughness effects for RCF life equations in rolling element bearing applications.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Engineering, Mechanical
Steven J. Lorenz, Farshid Sadeghi, Hitesh K. Trivedi, Mathew S. Kirsch, Chinpei Wang
Summary: This study investigates the effect of prior austenite grain refinement on rolling contact fatigue (RCF) using a finite element model and continuum damage mechanics. The research reveals that finer grain diameter leads to exponentially improved fatigue performance, with resistance stress increasing as grain diameter is refined, while the damage rate exponent shows no correlation with grain diameter. The results of RCF simulations demonstrate good agreement with experimental data from open literature, and a predictive fatigue life equation is constructed to evaluate RCF performance in non-conformal contacts.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Industrial
Bin Xie, Yanzhong Wang, Yunyi Zhu, Peng Liu, Yu Wu, Fengxia Lu
Summary: In this study, a physical model for analyzing the reliability of ACBB considering the coupled effect of RCF damage and wear is proposed. The proposed model is validated through a practical example of ACBB.
RELIABILITY ENGINEERING & SYSTEM SAFETY
(2024)
Article
Engineering, Mechanical
Predrag Andric, Sebastian Echeverri Restrepo, Junbiao Lai, Cornelis H. Venner, Erik Vegter
Summary: Martensite decay due to large scale microstructural alterations is the main fatigue process in bearing applications. The study demonstrates that the decay is mainly driven by the positive components of the principal subsurface stress tensor. The analysis provides mechanistic insights into why the fastest material decay occurs at specific depths.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Engineering, Mechanical
Akhil Vijay, Farshid Sadeghi
Summary: This paper presents a two-stage approach for modeling the initiation and propagation phases of rolling element bearing failures. By using crystal plasticity and cohesive elements, the method is able to simulate the initiation and growth of cracks, showing good correlation with experimental data.
TRIBOLOGY INTERNATIONAL
(2022)
Article
Engineering, Mechanical
Knut Andreas Meyer, Rostyslav Skrypnyk, Martin Pletz
Summary: The study introduces a faster cyclic finite element simulation method that maintains contact between the wheel and rail throughout the simulation, and is open-source as an Abaqus plugin, enabling other researchers to study the coupling of rolling contact loading with plastic deformation.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Busra Duran, Jerome Cavoret, David Philippon, Fabrice Ville, Arnaud Ruellan, Frank Berens
Summary: This study analyzes the changes in the physicochemical properties and tribological performances of gear transmission oils during field operation, finding differences from traditional engine oils.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Baocheng Liu, Hongsheng Chen, Jun Zhou, Jing Wang, Wenxian Wang, Xiaochun Chen, Sanxiao Xi
Summary: This study used fast hot pressing sintering to fabricate WC/AlCoCrFeNi2.1 metal matrix composites (MMCs). It was found that the addition of reinforced particles increased the microhardness, nanoindentation and wear resistance of the MMCs. During frictional processes, an oxide film formed, providing material protection, enhancing stability and reducing friction-induced losses.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Pradip Kumar Verma, Alok Singh
Summary: This study investigates the mechanical properties and wear resistance of CoMoMnNiV high entropy alloy reinforced aluminium matrix composite processed through stir-squeeze casting assisted with an ultrasonic transducer. The results show significant improvements in mechanical properties and wear resistance, with the composite containing 8 wt% HEA demonstrating the highest resistance to wear. Optical microscopy, SEM, and an optical profilometer were used for a thorough examination of the microstructure and worn surface.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Zhenghai Yang, Yingjian Song, Jinlong Jiao, Wenbo Li, Bao Shangguan, Yongzhen Zhang
Summary: This study investigated the friction, wear properties, and current-carrying properties of copper-graphite composites paired with brass C28000. The results showed that the current-carrying properties of the composite materials were excellent, but their wear rate was the main limiting factor. Furthermore, an increase in the thickness of the graphite layer led to an improvement in the uniformity of damage.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Moustafa Mahmoud Yousry Zaghloul, Karen Steel, Martin Veidt, Michael T. Heitzmann
Summary: This research evaluates and compares the impact of different material types on the tribological characteristics of Polyamide 6 composites, and finds that glass fiber-reinforced Polyamide 6 exhibits better friction and wear performance under high-pressure velocity factors.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Shaoqing Qin, Lida Zhu
Summary: In this paper, the surface and subsurface damage of laser assisted grinding CrCoNi medium entropy alloys were investigated using molecular dynamics simulations. The results showed that the application of laser energy can reduce cutting forces and minimize subsurface damage.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Kaikui Zheng, Youxi Lin, Tingzheng Lai, Chenghui Gao, Ming Liu, Zhiying Ren
Summary: The study investigated the use of waste foundry resin-bonded sand as a substitute for copper in resin-based brake material. It found that the waste sand was more favorable for improving the overall friction and wear properties of the material compared to copper. Waste sand benefited the material by forming a friction layer, leading to increased friction coefficient and stability. Brake material with 10-15% waste sand showed excellent heat-fade resistance.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Dayang Li, Fanhao Zhou, Yutong Gao, Kun Yang, Huimin Gao
Summary: This article introduces a continuous prediction model based on deep learning for predicting the power output of steam turbines. The model uses long short term memory (LSTM) method to develop a trend prediction model and optimizes the prediction model through feature selection method. Experimental results show that the model outperforms other models in terms of prediction performance.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Tomohiro Toyoda, Ryo Yasuike, Toshihiro Noda
Summary: In this study, a elasto-plastic constitutive model of friction incorporating the concept of superloading surface was developed based on the subloading friction model. The proposed model achieves a smooth transition of friction by describing the evolution rule of structure, treating the state with static friction coefficient larger than kinetic friction coefficient as the bulkiness of structure. The positive definiteness of the plastic multiplier, loading condition, and material parameters were derived, and the validity of the proposed model in accordance with the subloading-friction model was confirmed through a stick-slip simulation of a mass-spring system.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
P. Balaji, B. Surya Rajan, K. Sathickbasha, P. Baskara Sethupathi, Deviga Magadevan
Summary: This study emphasizes the importance of using a variety of solid lubricants with different oxidation temperature regimes to enhance the tribological performance of brake pads.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Jian Ma, Yancong Liu, Javad Mostaghimi, Na Zhang
Summary: This paper investigates the influence of preparation strategies on the lubrication properties of surface textures. Three laser scanning strategies are proposed to achieve a sinusoidal textured surface, and the evolution of surface structure and chemical composition is discussed. The findings show that ridge structures enhance anti-wear properties but also increase the friction coefficient. However, the oil cover preparation method prevents the formation of ridges and improves wettability.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Mohammad Roostaei, Arvin Taghizadeh Tabrizi, Hossein Aghajani
Summary: In this research, the Al2O3/MoS2 nanocomposite coating layer was successfully applied on the surface of Ti-6Al-4 V alloy. The relation between the surface characteristics and wear resistance of the coating was studied using atomic force microscopy analysis and pin-on-disk wear test method. The results showed that the nanocomposite coating significantly reduced the wear rate and provided an equation to calculate the Lancaster coefficient.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Musa Bilgin, Sener Karabulut, Halil Karakoc, Yunus Kayir, Murat Sarikaya
Summary: This study investigates various methods to improve the machinability efficiency of Inconel 718 alloy while considering their effect on microstructural properties. The results show that hot+PMQL, hot+SiCNMQL, and hot+Al2O3-NMQL contribute significantly to the improvement of machinability characteristics. The EBSD analysis also reveals that a limited area is affected by heat in the hot machining environment and that the removal of the heated layer during milling process helps preserve the microstructure.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Q. Gao, Y. Fan, Y. G. Wu, J. L. Liu, J. Wang, L. Li
Summary: Fretting wear significantly affects the hysteresis behavior of the contact surface and leads to joint degradation. This study investigates the influence of harmonic normal force on the evolution of interface morphology and contact parameters with fretting wear. The results show that the harmonic normal force can significantly influence the hysteresis loop and the energy dissipation distribution on the contact surface.
TRIBOLOGY INTERNATIONAL
(2024)
Article
Engineering, Mechanical
Benjamin Weiland, Floriane Leclinche, Anis Kaci, Brigitte Camillieri, Betty Lemaire-Semail, Marie -Ange Bueno
Summary: This study presents a systematic approach to generating control signals for a tactile simulator that simulate the touch of textile fabrics. By using a friction modulation tactile surface and acquiring forces from real surfaces with artificial finger mimicking fingerprints, control signals are generated and processed in the frequency domain before sending them to the tactile stimulator. The study focuses on the potential benefits of incorporating fingerprint information in fabric simulations to achieve a more realistic tactile perception. A sensory analysis with 36 participants using the generated control signals showed better discrimination without fingerprint information.
TRIBOLOGY INTERNATIONAL
(2024)