Article
Engineering, Mechanical
Georges Amine, Nicolas Fillot, David Philippon, Nicolas Devaux, Johnny Dufils, Etienne Macron
Summary: This study presents a dual experimental-numerical approach to investigate oil film thickness and friction in a wide elliptical TEHL contact under different sliding conditions. The experimental results show different trends of film thickness variation for different slide-to-roll ratios. The numerical model accurately predicts film thickness and friction behavior under a wide range of sliding conditions.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Nanoscience & Nanotechnology
Sorin-Cristian Vladescu, Chiharu Tadokoro, Mayu Miyazaki, Tom Reddyhoff, Takuo Nagamine, Ken Nakano, Shinya Sasaki, Yoshinobu Tsujii
Summary: This study investigates the interactions between concentrated polymer brushes (CPBs) and laser-produced surface texture (LST). The results show that the combination of CPB-LST can reduce the friction coefficient and improve the durability of CPBs through a lateral support mechanism offered by the textured micro-features. The study also reveals the failure mechanisms of CPBs, which are important for the development of CPBs for future applications.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Automation & Control Systems
Rafael Luciano Dalcin, Valcir Marques de Menezes, Alexandre da Silva Rocha, Samara Paulin de Moraes, Leonardo Bottega Affonso, Tiago Cousseau, Carlos Henrique da Silva
Summary: This research investigates the relationship between roughness, film thickness, and friction coefficient with pitting wear resistance in forged and plasma-nitrided gears during rolling-sliding contact fatigue. The study finds that gears nitrided with 24 vol% N2 exhibit the lowest pitting wear rates, attributed to an optimal balance of surface hardness, fracture toughness, compound layer depth, and surface phases. The most severe pitting damage occurs in the dedendum and pitch line regions, which have the highest Hertz contact pressure. Increasing roughness intensifies pitting wear, but there is no apparent correlation with the maximum shear stress field in the subsurface. Nitrided gears with 24 vol% N2 also have a greater film thickness at the end of the contact fatigue, providing better protection, reduced friction, and pitting wear.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Engineering, Mechanical
Febin Cyriac, Xin Yi Tee, Sendhil K. Poornachary, Pui Shan Chow
Summary: The study found that organic friction modifiers (OFMs) can reduce friction under heavy loads, low sliding speeds, and high temperatures, forming a boundary lubrication film containing OFM. While the adsorption of OFM on the metal surface did not directly correlate with surface coverage and tribofilm thickness, the reduction in friction mechanism may involve other localized processes at the interface.
Article
Chemistry, Physical
Panjun Wang, Lingwei Ma, Xuequn Cheng, Xiaogang Li
Summary: Low alloy steels with different textures were prepared by advanced thermo-mechanical processes, and their microstructures, passive performance, and chloride-ion pitting behaviors were characterized using various techniques. The results revealed that crystallographic orientation significantly affects passive performance and pitting resistance in bicarbonate solution, with (1 1 1) texture showing better resistance compared to (1 1 0) texture.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Hu Li, Tianbo Duan, Omer Sher, Yuanyuan Han, Raffaello Papadakis, Anton Grigoriev, Rajeev Ahuja, Klaus Leifer
Summary: Graphene, with its chemically inert surface, has been non-covalently functionalized using pi-pi stacking interactions for enhanced ammonia detection in this study. The use of 5,5'-Di(4-biphenylyl)-2,2'-bithiophene molecules resulted in a 3-fold higher sensitivity compared to pristine graphene, showcasing the potential for chemical detection applications.
Article
Physics, Condensed Matter
I Cojocariu, M. Jugovac, A. Locatelli, T. O. Mentes
Summary: L3M 2,3 M 2,3 Auger transition near the L3 resonance of ferromagnetic Fe films on W(110) is studied. The Auger peak kinetic energies exhibit typical Raman behavior for photon energies below the absorption threshold. Constant kinetic energy behavior is observed below the L3 resonance, regardless of the number of Fe layers. Strong x-ray circular magnetic dichroism is observed in the entire L3M 2,3 M 2,3 Auger spectrum, with slight variations in the dichroic signal attributed to exchange interactions.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Engineering, Mechanical
G. Boidi, F. J. Profito, A. Kadiric, I. F. Machado, D. Dini
Summary: This study explores the use of different sintering manufacturing techniques to achieve superior performance in lubricated point contacts. The research shows that reducing porosity can improve tribological performance and promote friction reduction in specific configurations.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Rahul Kumar, Maksim Antonov, Piotr Klimczyk, Valdek Mikli, Dmitri Gomon
Summary: This study tested the performance of cutting tools containing superhard phases under dry machining and surface fatigue conditions. Through the analysis of wear mechanisms and material performance based on wear scar and fatigue test area, it was found that Al2O3-20cBN15ZrO2 material exhibited the lowest wear under dry cutting conditions.
Article
Materials Science, Multidisciplinary
Scott B. Donald, Jeff A. Stanford, William A. Talbot, Cheng K. Saw, Brandon W. Chung, W. McLean
Summary: The oxidation behavior of a plutonium metal alloy containing approximately 1.5% Ga in dry air was studied using a combination of FIB-SEM, AES, and XRD. The study revealed the growth of oxide layer and changes in chemical composition during oxidation process. Initial sample preparation and electropolishing were found to influence the experimental results.
Article
Materials Science, Multidisciplinary
Scott B. Donald, Jeff A. Stanford, John M. Haschke, Denise D. Ashley, William A. Talbot, David J. Roberts, Art J. Nelson, Brandon W. Chung, W. McLean
Summary: Auger electron spectroscopy (AES) was used to characterize the oxide scale on a Ga-plutonium metal alloy, revealing its thickness and chemistry. The parabolic kinetics of the Pu-Ga alloy were determined as a function of relative humidity and oxygen partial pressure, showing that the reaction rate was independent of oxygen pressure and had a power-law relationship with humidity.
Article
Materials Science, Multidisciplinary
Xiaoqing Ni, Chaofang Dong, Liang Zhang, Kui Xiao, Xuequn Cheng, Xiaogang Li
Summary: This study investigates the properties of a passive film formed on pure nickel in an anaerobic alkaline solution through first-principles calculations and electrochemical experiments, showing consistency between the two methods. It reveals that the density of nickel vacancies in the passive film is temperature and film-formation potential dependent, while the diffusion coefficient of nickel vacancies increases with temperature.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2021)
Article
Materials Science, Multidisciplinary
Xiaoyan Liu, Luhua Wang, Yongjian Zhang, Xitao Wang, Jinguo Wang, Moon J. Kim, Hailong Zhang
Summary: The study focuses on solving the interfacial bonding issue in Cu/diamond composites by inserting a modifying layer between Cu and diamond. Cu/Cr bilayer thin films were deposited on a diamond substrate and the microstructural evolution of the Cr interlayer upon heat treatment was studied. It was observed that a thin Cr layer forms on top of the Cu film through Cr diffusion at high annealing temperatures.
Article
Chemistry, Physical
Maxim Shtern, Maxim Rogachev, Yury Shtern, Dmitry Gromov, Alexander Kozlov, Ivan Karavaev
Summary: The study focuses on developing effective thin-film multilayer contact systems for thermoelements using magnetron ion-plasma sputtering, with structures and materials selected to enhance thermoelectric performance. Introducing diffusion-barrier layers is shown to increase the reliability and stability of contact systems. By analyzing physicochemical and Auger electron spectroscopy data, factors affecting the stability and thermal stability of contact systems are identified.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Engineering, Mechanical
Thi-Na Ta, Jeng-Haur Horng
Summary: This study investigates the synergistic effects of methyltrioctylammonium bis(trifluoromethylsulfonyl)imide [N1888] [NTf2] ionic liquid (IL) with zinc dialkyldithiophosphate (ZDDP) and zinc oxide (ZnO) nanoparticles (NPs) as hybrid additives in a circulation oil for steel-steel contacts at different temperatures. The results show that the additions of single additives (IL, ZDDP, and ZnO NPs) can improve the tribological performance of the circulation oil. The mixture of IL and ZDDP exhibits superior friction-reducing and wear-reducing properties compared to the IL + ZnO formulation.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2023)
Article
Engineering, Mechanical
Romain Quiban, Christophe Changenet, Yann Marchesse, Fabrice Ville
Summary: This study investigates the transition between churning and windage phenomena for a spur gear under oil sump lubrication, proposing a criterion to indicate which power loss model to use based on torque measurements at different oil immersion levels.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Mechanical
P. Brossier, D. Niel, C. Changenet, F. Ville, J. Belmonte
Summary: The present study conducted measurements on rolling element bearing thermal behavior using a dedicated test rig, including power losses, oil lubrication tests, penetration ratio measurements, and establishment of a thermal network. The developed model showed good agreements with experiences for rolling element bearing inner thermal behavior under specific test conditions.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
T. Touret, C. Changenet, F. Ville, J. Cavoret
Summary: This study presents an experimental investigation on a FZG test rig to highlight the influence of micropitting on power losses and temperatures in a geared system. The impact of micropitting on power losses and temperatures was evaluated with specific characterization tests, and gear surface roughness modification was monitored during these tests. The results show increased power loss and oil temperature due to micropitting development, with a correlation between power loss and temperature variations and surface feature measurements.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
J. B. Boni, C. Changenet, F. Ville
Summary: Planetary gears are widely used due to their high reduction ratio in a compact size, with lubrication methods like injection or splash lubrication being commonly employed. This paper highlights the importance of centrifugal effects in forming an oil ring inside the reducer, providing insights into churning power losses under different operating conditions and oil characteristics when centrifugal forces are not sufficient.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Multidisciplinary
Y. Marchesse, M. Ruzek, F. Ville, P. Velex
Summary: It is commonly acknowledged that load-independent losses in high-speed gears can increase significantly at peripheral speeds exceeding 100 m/s. This study demonstrates that the installation of axial flanges close to gear faces can greatly reduce windage power losses. The research also examines the impact of various parameters, such as the number of flanges, gear module, and gear geometry, on power loss reductions. Ultimately, an approximate equation is proposed for estimating power loss reductions during the design phase.
FORSCHUNG IM INGENIEURWESEN-ENGINEERING RESEARCH
(2021)
Article
Engineering, Mechanical
Romain Quiban, Nicolas Grenet De Bechillon, Thomas Touret, Pierre Navet, Yasser Diab, Jerome Cavoret, Fabrice Ville, Christophe Changenet
Summary: A semi-empirical model is used to study the friction coefficient, where the lubricant is modeled as an Eyring-Reynolds fluid and rough surfaces are described with two parameters using a stochastic approach.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
V Ripard, D. Goncalves, F. Ville, J. H. O. Seabra, J. Cavoret, P. Charles
Summary: The study analyzed lubrication starvation using the Starvation Degree parameter through tests with different operating conditions and types of greases to prevent damage such as scuffing.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2022)
Article
Engineering, Mechanical
Ton Lubrecht, Nans Biboulet, Kees Venner
Summary: The paper summarizes the contributions of Dowson, Higginson, and Hamrock to numerical line contact elastohydrodynamic lubrication and film thickness prediction in elliptical contacts, finding that the predicted results are accurate, especially under pure rolling conditions.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Engineering, Mechanical
Lucas Fourel, Jean-Philippe Noyel, Etienne Bossy, Xavier Kleber, Philippe Sainsot, Fabrice Ville
Summary: A mesoscopic model for simulating the initiation of rolling contact fatigue (RCF) cracks is proposed in this study, using Finite Element Method (FEM) with cubic elasticity and polycrystalline geometry. Results show consistent initiation depths.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Materials Science, Coatings & Films
Nicolas Grenet-de Bechillon, Thomas Touret, Jerome Cavoret, Christophe Changenet, Fabrice Ville, Dhafer Ghribi
Summary: This paper investigates the strong coupling between friction power losses and film thickness, and proposes a new test method to study scuffing with film thickness as a key parameter. This method allows for film thickness variation with minimal friction losses and temperature changes, revealing the importance of film thickness in scuffing. The test results show that even in full film lubrication, asperity contact can be achieved potentially through the collapse of the oil film.
TRIBOLOGY-MATERIALS SURFACES & INTERFACES
(2022)
Article
Engineering, Mechanical
P. Navet, J. Cavoret, F. Ville, C. Changenet, D. Ghribi
Summary: This study conducts experiments to analyze starvation conditions for high slide-to-roll ratio, similar to those of gears. It proposes a new oil-off test procedure and highlights the positive effect of low viscosities of residual oil on starved conditions. Additionally, it introduces a new inverse method to estimate central oil film thickness during oil-off phases, which is consistent with existing models and suitable for severe starvation.
TRIBOLOGY TRANSACTIONS
(2023)
Article
Engineering, Mechanical
L. Darul, T. Touret, C. Changenet, F. Ville
Summary: This study presents a theoretical analysis of power losses in an oil-jet lubricated deep groove ball bearing. The model focuses on the physics of unloaded rolling elements and aims to solve the problem of estimating dissipation sources in the absence of applied load. The model is compared with global power loss models and shows that unloaded rolling elements can contribute up to 40% of the losses with a 5% applied radial load.
TRIBOLOGY TRANSACTIONS
(2023)
Article
Engineering, Mechanical
F. de Cadier de Veauce, L. Darul, Y. Marchesse, T. Touret, C. Changenet, F. Ville, L. Amar, C. Fossier
Summary: This article presents an experimental study on load-independent power losses in oil-jet lubricated deep-groove ball bearings. The influence of factors such as rotational speed, lubricant temperature, oil flow rate, and bearing dimensions on power losses were quantified through experiments. A load-independent power losses model for rolling element bearings, proposed in a previous article, was used to simulate the experiments, and the results were compared with measurements. Good agreement was found on the power losses in low-loaded deep-groove ball bearings.
TRIBOLOGY TRANSACTIONS
(2023)
Article
Engineering, Mechanical
Gabriel Lanaspeze, Berengere Guilbert, Lionel Manin, Fabrice Ville
Summary: A quasi-static chain drive model is proposed for simple two sprocket drives in single speed cycling application. Kinematics of the transmission is determined and both tensions into the links and contact forces are calculated. The results suggest that roller displacement should be considered in future studies on chain drive efficiency.
MECHANICS & INDUSTRY
(2022)
Article
Engineering, Mechanical
Ton Lubrecht, Kees Venner
Summary: The current paper focuses on Dr. R. Gohar's research on impacting ball and pressure spike measurement. It discusses contributions from other researchers in these two fields and combines them in a numerical study. The study reveals the position and velocity variation of the pressure spike over time, concluding that its shape also varies with time.
Article
Engineering, Mechanical
Huiyi Yang, Yang Xu, Chao Xu
Summary: This study focuses on the impact of dry friction interfaces on the dynamics of jointed structures, particularly on the statistics of contact pressure distribution. Through experimental and simulation analysis, it is found that surface roughness and contact load have significant effects on contact area, contact stiffness, and mean contact pressure.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2024)
Article
Engineering, Mechanical
Guanglan Hu, Houfu Dai
Summary: The effect of metal coating on the machinability of cubic silicon carbide was investigated using molecular dynamics simulation. The results showed that the type of coating has a significant impact on cutting force, surface morphology, stress, and tool wear. Among the three metals studied, Cu coating had the greatest impact on improving cutting performance.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2024)
Article
Engineering, Mechanical
Yunfan Liu, Guozheng Ma, Lina Zhu, Cuihong Han, Zhen Li, Bin Zhang, Haichao Zhao, Haidou Wang, Shuying Chen
Summary: The service performance of coated self-lubricating spherical plain bearings can be improved by applying self-lubricating coatings, especially double-sided coatings. The presence of a large-area and complete mixed friction transfer film on the contact surfaces can cause a signal downstage before the signal mutation stage.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2024)
Article
Engineering, Mechanical
Yakup Artun, C. Oktay Azeloglu, Gokhan Taylan
Summary: This article investigates the tribological properties of polymer journal bearings, particularly focusing on radial journal bearings made from UHMWPE and POM materials with different surface qualities. The study examines the performance of these bearings under varying load and speed conditions, and analyzes the relationship between material and surface roughness in tribological performance.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2024)