Article
Chemistry, Physical
Ajay Chouhan, Tarun K. Sarkar, Sangita Kumari, K. L. N. Sivakumar, H. Sugimura, Om P. Khatri
Summary: The study explores the use of a nanocomposite material synthesized from reduced graphene oxide and polystyrene for preparing a self-lubricating thin film, which exhibits excellent mechanical strengthening and lubrication properties, showing significantly lower friction on a silicon substrate. The uniform thin film with a thickness of 850nm is coated on the silicon surface using a spray pyrolysis deposition technique.
APPLIED SURFACE SCIENCE
(2021)
Article
Engineering, Mechanical
Zuobing Wu
Summary: The study shows that the elastic response of the substrate can be effectively rendered in the hybrid scheme by combining an atomistic description of the near region with a coarse-grained description of the far region. In the application of the multi-scale method to investigate the tribological properties of multi-layer molecular thin-film lubrication, it is found that the systematic static friction coefficient decreases as the molecular layer thickness in the fluid film increases, reducing friction and wear of the system.
Article
Chemistry, Multidisciplinary
Samuel D. Fernandez-Silva, Miguel A. Delgado, Claudia Roman, Moises Garcia-Morales
Summary: Nanocellulose demonstrated noticeable friction-reducing and anti-wear properties in vegetable oil, depending on the nanocellulose concentration, base oil composition, and applied pressure. Adding 3.3 wt.% or higher nanocellulose in castor oil-rich mixtures can achieve excellent tribological performance.
Article
Engineering, Mechanical
Youyu Di, Shuai Zhang, Xi-Qiao Feng, Qunyang Li
Summary: The study demonstrates that different types of self-assembled films (SAFs) exhibit varying frictional performance, which is dependent on the interaction between their molecular structures and substrates. By guided self-assembling, control over the molecular structures of SAFs can be achieved, leading to rational friction tuning.
ACTA MECHANICA SINICA
(2021)
Article
Engineering, Marine
Korosh Khorshidi, Babak Soltannia, Mahdi Karimi, Ali Ghorbani
Summary: The current study investigates the free vibration analysis of a sandwich plate in contact with quiescent fluid. The structure consists of an electro-rheological (ER) fluid core and two laminated composite skins. The fluid, which is ideal, interacts partially with the plate, and the fluid potential velocity is derived satisfying the continuity equation. The developed model focuses on the nonlinear analysis of an ER sandwich panel coupled to an ideal fluid, and the obtained results can guide the future design of composite ER panels.
Article
Multidisciplinary Sciences
Yanzhong Wang, Kai Yang, Xiaomeng Chu, Wen Tang, Changyong Huang
Summary: An engineering calculation model is introduced to analyze point-contact elastohydrodynamic lubrication of spiral bevel gears, revealing the transient lubrication characteristics and film thickness variations during the meshing process.
SCIENTIFIC REPORTS
(2021)
Article
Engineering, Mechanical
Leoluca Scurria, Tommaso Tamarozzi, Oleg Voronkov, Dieter Fauconnier
Summary: The study compared the performance of different methods under various elastohydrodynamic lubrication conditions, quantifying their differences to understand the advantages and limitations of each.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Mechanical
Stephan Basten, Lukas Seis, Manuel Oehler, Benjamin Kirsch, Hans Hasse, Jan C. Aurich
Summary: This paper investigates the influence of different cooling and lubrication conditions on the tribological behavior at extremely high contact pressures. The analysis considers the thermo-mechanical load, coefficient of friction, and surface topography of the friction partners. The use of sub-zero metalworking fluids achieves a high lubricating effect even at high contact pressures.
Article
Engineering, Mechanical
J. C. Atwal, R. K. Pandey
Summary: This study investigates the performance behaviors of a fluid film thrust bearing with a newly conceived micro-texture on pads, finding that the new texture increases the minimum film thickness by 48% and reduces the friction coefficient by 24% compared to conventional plain pad cases.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Multidisciplinary
Kang-Seok Kim, Deug-Woo Lee, Mi-Ru Kim, Yoong-ho Jung
Summary: In this study, an experimental device was developed to verify the effectiveness of lubrication analysis. The study found that the slope parameter of the friction surface and the relative slope of the pad bearing surface have an impact on friction characteristics.
Review
Engineering, Mechanical
Sitae Kim, Dongil Shin, Alan B. Palazzolo
Summary: This review summarizes the effects of nonlinear elements in fluid film journal bearings on rotor-bearing systems, including sub- and super-synchronous, chaos and thermally induced instability responses. It also discusses the importance of nonlinear, thermo-elasto-hydrodynamic aspects of journal bearings in high-performance turbomachines, and presents nonlinear solution methodologies and numerical tools for analyzing nonlinear vibration responses induced by bearings.
JOURNAL OF TRIBOLOGY-TRANSACTIONS OF THE ASME
(2021)
Article
Chemistry, Analytical
Stephan Emmrich, Marcel Plogmeyer, Dirk Bartel, Christoph Herrmann
Summary: The study utilized an optimized thin-film sensor system to measure temperature changes during rolling contacts under heavy duty conditions, conducting extensive tests on a two-disk test rig. The results demonstrated the complex processes within rolling contacts and the strong interaction between pressure, friction, and temperature within the contact zone.
Article
Engineering, Mechanical
Zhongliang Xie, Yuxin Tian, Jiaxin Li, Peng Du
Summary: The paper aims to reveal the lubrication bearing mechanism of double-film bearing under different conditions. Modified lubrication models are established and the influences of coupling factors on lubrication characteristics are explored. The lubrication mechanism of the double-liquid film interface is elucidated.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Jingjing Chen, Ruyi Gou, Xun Luo, Kunyao Li, Jinfa Zhang, Shunjun Long
Summary: This study investigated the friction and wear behavior of polycrystalline diamond compact (PDC) after leaching cobalt and the evolution of the friction film with nano-molybdenum disulfide (MoS2) lubricating additives. The results showed that the friction coefficient and wear rate of different materials and PDC after leaching cobalt were influenced by the amount and evolution behavior of the friction film formed on the sliding interface, as well as the filling effect of lubricating additives. Different materials and PDC after leaching cobalt exhibited different wear mechanisms due to dissimilar chemical reactions during the sliding process.
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
(2023)
Article
Engineering, Mechanical
Daofei Wang, Jialong Yang, Pengchong Wei, Wei Pu
Summary: This article focuses on the application of grease lubrication in rolling element bearings and the establishment of a mixed EHL model. Experimental results show that the grease friction behavior corresponds well with the variation of grease film thickness.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Blaza Stojanovic, Sandra Gajevic, Nenad Kostic, Slavica Miladinovic, Aleksandar Vencl
Summary: This study presents a novel methodology for evaluating the tribological properties of aluminum matrix nanocomposites. The wear rate was analyzed using design of experiments and a regression model was developed to establish the relationship between the factors and the wear rate. The combination of optimization methods determined the optimal parameters with the highest wear resistance.
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2022)
Review
Engineering, Mechanical
Sasa Vasiljevic, Jasna Glisovic, Blaza Stojanovic, Aleksandar Vencl
Summary: Wear of brake friction pairs not only reduces the active safety of vehicles, but also affects the environment and human health. In order to reduce brake wear and the formation of particles, new materials and various processing technologies are being introduced. Coating deposition techniques play a significant role in reducing brake wear rates.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2022)
Editorial Material
Engineering, Mechanical
Aleksandar Vencl
INDUSTRIAL LUBRICATION AND TRIBOLOGY
(2022)
Article
Engineering, Mechanical
Michal Michalec, Jakub Hurnik, Jan Foltyn, Petr Svoboda
Summary: Hydrostatic bearings are important components in various industrial applications, but large-scale bearings often face complications with pad alignment and levelling. A contactless measurement method based on optical tracking has been developed for film thickness diagnostics of hydrostatic bearings. The results show good agreement between the optical measurement and proximity sensors, as well as analytical calculations. This method can be utilized to improve pad levelling, alignment, or film thickness diagnostics of hydrostatic bearing pads.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2023)
Article
Engineering, Chemical
S. Reitschuster, E. Maier, T. Lohner, K. Stahl, K. Bobzin, C. Kalscheuer, M. Thiex, P. Sperka, M. Hartl
Summary: The potential of diamond-like carbon (DLC) coatings on thermoplastic polymers for reducing friction and wear in highly stressed rolling-sliding contacts was evaluated. The results showed that DLC coatings could reduce friction on the considered polymers under specific lubrication conditions. In terms of wear behavior, DLC coatings showed potential especially under severe mixed lubrication conditions.
Article
Engineering, Multidisciplinary
Pavel Cipek, Martin Vrbka, David Rebenda, David Necas, Ivan Krupka
Summary: This study focuses on the role of albumin protein in the lubrication process of synovial joints. Experimental results show that hyaluronic acid reduces friction and increases the area of albumin adsorbed boundary layer, while phospholipids have the opposite effect. The combination of albumin and c-globulin has no significant effect on the particles count of albumin clusters adsorbed in the contact.
ENGINEERING SCIENCE AND TECHNOLOGY-AN INTERNATIONAL JOURNAL-JESTECH
(2022)
Article
Engineering, Chemical
K. Bobzin, C. Kalscheuer, M. Thiex, P. Sperka, M. Hartl, S. Reitschuster, E. Maier, T. Lohner, K. Stahl
Summary: The purpose of this study was to improve the wear resistance of polymers in highly stressed tribological contacts by developing and depositing diamond-like carbon (DLC) coatings on polymers. The coatings showed the ability to undergo high plastic deformations without delamination and the possibility of forming a composite layer under dry conditions. Additionally, changes in sp(2) chain and sp(2) cluster size and distribution were observed during dry contact conditions.
Review
Chemistry, Physical
Slavica Miladinovic, Blaza Stojanovic, Sandra Gajevic, Aleksandar Vencl
Summary: The fast development of the automotive industry has led to increased demands for fuel efficiency, weight reduction, and increased reliability. Hypereutectic Al-Si alloys, with their good thermal and electrical conductivity, high strength to weight ratio, and corrosion resistance, have become popular in the automotive and aerospace industries. However, the higher Si content in the alloy can affect its properties, necessitating grain refinement. Various manufacturing technologies, heat treatments, and the addition of grain refiners have been used to improve the properties of hypereutectic Al-Si alloys.
Article
Engineering, Mechanical
Aleksandar Vencl, Petr Svoboda, Simon Klancnik, Adrian But, Milos Vorkapic, Marta Harnicarova, Blaza Stojanovic
Summary: In this study, three different ratios (0.2%, 0.3%, and 0.5%) of alumina in two sizes (approx. 25 and 100 nm) were used to improve the wear characteristics of ZA-27 alloy-based nanocomposites. The materials were produced through mechanical alloying and compocasting processes. Wear tests were conducted under lubricated sliding conditions and the experimental results were analyzed using the response surface methodology (RSM) to develop a mathematical model for the wear rate. Artificial neural network (ANN) was used to evaluate the accuracy of prediction, with an overall regression coefficient of 0.98729.
Article
Acoustics
Lubos Smolik, Jan Rendl, Milan Omasta, Miroslav Byrtus, Petr Sperka, Pavel Polach, Martin Hartl, Michal Hajzman
Summary: This paper investigates the effects of mechanically induced textures on the stability of journal bearings, focusing on lightly loaded bearings commonly used in vertical rotors and microturbines. The results show that textures near the minimum oil film thickness can improve stability at low loads, but have little effect at a specific load of 0.15 MPa. The paper also discusses computational methods for dealing with cavitation and highlights the sensitivity of numerical results to the density of computational mesh.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Chemical
Michal Michalec, Martin Ondra, Martin Svoboda, Jiri Chmelik, Petr Zeman, Petr Svoboda, Robert L. Jackson
Summary: This study proposes a new two-parameter method using Computational Fluid Dynamics (CFD) to estimate the optimal proportions of a hydrostatic bearing pad. The method considers the recess area and position, and was found to reduce energetic loss by 20% compared to the traditional one-parameter approach. The results demonstrate the versatility and effectiveness of this methodology in designing optimal hydrostatic bearings with minimum energetic loss in low-speed conditions.
Article
Engineering, Electrical & Electronic
Michal Michalec, Jan Foltyn, Tomas Dryml, Lukas Snopek, Dominik Javorsky, Martin Cupr, Petr Svoboda
Summary: This study focuses on finding assembly error tolerances for common types of segmented errors in hydrostatic bearing sliders. The experimental results can be used to determine the required film thickness.
