Showing papers in "Tribology Transactions in 2019"
TL;DR: NiTiNOL 60, or 60NiTi, is a nickel-titanium alloy being investigated for bearing and gear applications as mentioned in this paper, which has many desirable properties for these applications.
Abstract: NiTiNOL 60, or 60NiTi, is a nickel–titanium alloy being investigated for bearing and gear applications. 60NiTi has many desirable properties for these applications; for example, it is hard,...
23 citations
TL;DR: In order to improve the toughness of NiP coatings, Ti particles were introduced into the plating solution to produce a Ni-P-Ti composite coating (on API-X100 steel) as discussed by the authors.
Abstract: In order to improve the toughness of Ni-P coatings, Ti particles were introduced into the plating solution to produce a Ni-P-Ti composite coating (on API-X100 steel), which was subsequently...
22 citations
TL;DR: In this article, the authors investigated the correlation between the friction-induced oscillation of a wheelset-track system and curve radius and explained the typical phenomenon of rail corrugation in metros.
Abstract: © 2019, © 2019 Society of Tribologists and Lubrication Engineers. The purpose of this article is to investigate the correlation between the friction-induced oscillation of a wheelset–track system and curve radius and to explain a general phenomenon of rail corrugation based on the viewpoint of friction-induced oscillation. The typical phenomenon of rail corrugation in metros is that corrugation generally arises when the curve radius is quite small, whereas it rarely occurs when the curve radius is larger or on a straight track. Different multibody models of the vehicle–track system and finite-element models of the multiple-wheelset–track system with different curve radii are established, respectively. According to the creep force analyses and unstable vibration analyses, the correlation between the creep force and friction-induced oscillation can be identified. Then the effect of the track curve radius on the friction-induced oscillation of the wheelset–track system can be summarized, which provides an explanation of the typical phenomenon of corrugation.
21 citations
TL;DR: A tolerancing method highlighting trade-offs against key design variables of mechanical systems is proposed and applied to herringbone-grooved gas journal bearings, highlighting that the radius and viscosity have the greatest impact on the robustness.
Abstract: A tolerancing method highlighting trade-offs against key design variables of mechanical systems is proposed and applied to herringbone-grooved gas journal bearings. Gas bearings typically s...
20 citations
TL;DR: In this article, the tribological behavior of nanoparticles of titanium dioxide anatase TiO2 (A), graphene, and titanium dioxide + graphene added to the pure base oil group was investigated.
Abstract: This article investigates the tribological behavior of nanoparticles (NPs) of titanium dioxide anatase TiO2 (A), graphene, and TiO2 (A) + graphene added to the pure base oil group ΙΙ (PBO-GΙΙ). The...
20 citations
TL;DR: In this paper, the surface properties of electrical contact materials in terms of high friction coefficient and wear rate were improved by using diamond-like carbon (DLC) films containing different metal elements.
Abstract: In an effort to improve the surface properties of electrical contact materials in terms of high friction coefficient and wear rate, diamond-like carbon (DLC) films containing different metal elemen...
19 citations
TL;DR: In this paper, the shear stability of dry and water-contaminated lubricating calcium sulfonate complex greases is described using a novel aging method, where no shear softening is observed for the dry greases due to the good mechanical stability of the particle-like thickener structure.
Abstract: Calcium sulfonate complex greases have excellent extreme pressure, antiwear, and anticorrosion properties and are widely applied in rolling bearings, particularly in humid environments. In this article, the shear stability of dry and water-contaminated lubricating calcium sulfonate complex greases is described using a novel aging method. Unlike lithium and polyurea greases, no shear softening is observed for the dry greases due to the good mechanical stability of the particle-like thickener structure. For water-contaminated greases, no water separation was found during the prolonged aging. Instead, a homogeneous water–calcium sulfonate thickener micellar structure is generated. These micelles function as apparent thickeners and effectively increase the thickener concentration, which thickens the grease. This may explain why calcium sulfonate complex grease has excellent water absorption properties.
19 citations
TL;DR: In this paper, a solid contact asperity distribution model based on height and curvature was constructed to consider surface properties, such as skewness and kurtosis, corresponding to surface properties.
Abstract: In this study, we constructed a solid contact asperity distribution model based on height and curvature that is capable of considering surface properties, such as skewness and kurtosis, correspondi...
17 citations
TL;DR: In this article, the surface groove width is of great significance to the performance of the cylinder liner-piston ring (CLPR) with the different surface textures in marine diesel engines.
Abstract: Surface groove width is of great significance to the performance of the cylinder liner–piston ring (CLPR) with the different surface textures in marine diesel. However, little is understood about t...
17 citations
TL;DR: Hardened 60NiTi alloy, which possesses a unique set of desirable properties, has been considered as an attractive candidate for the bearing materials used in space mechanisms as discussed by the authors, however, the typical...
Abstract: Hardened 60NiTi alloy, which possesses a unique set of desirable properties, has been considered as an attractive candidate for the bearing materials used in space mechanisms. However, the typical ...
17 citations
TL;DR: In this paper, pure TiN coatings were applied on AISI 52100 steel surfaces with a magnetron sputterer at different direct current (DC) powers and N2 flows to develop a wear-resistant coating for sl...
Abstract: In this study, pure TiN coatings were applied on AISI 52100 steel surfaces with a magnetron sputterer at different direct current (DC) powers and N2 flows to develop a wear-resistant coating for sl...
TL;DR: In this paper, a lubrication model of the piston ring-cylinder liner tribosystem taking account of the honing texture was established, which was characterized by the impact of the texture parameter.
Abstract: A lubrication model of the piston ring–cylinder liner tribosystem taking account of the honing texture was established in this study. The impact of honing texture parameter, which was characterized...
TL;DR: In this paper, numerical analysis of mixed elastohydrodynamic lubrication (EHL) is applied to establish a test set of cycloidal gears for rotate vector reducers.
Abstract: Cycloidal gears play an important role in the performance of rotate vector (RV) reducers. In this article, numerical analysis of mixed elastohydrodynamic lubrication (EHL) is applied to establish a...
TL;DR: In this article, different Cu-based brake pads applied in high-speed railway trains were fabricated by the co-addition of Cr and CrFe particles, and the influence of the Cr/CrFe ratio on the tribological behavior of the brake pad was analyzed.
Abstract: Different Cu-based brake pads applied in high-speed railway trains were fabricated by the co-addition of Cr and CrFe particles, and the influence of the Cr/CrFe ratio on the tribological behavior o...
TL;DR: In this paper, three kinds of halogen-free ionic liquids (ILs) incorporating long-chain quaternary phosphonium as cations and dioctylsulfosuccinate (DOSS) as the anion were synthesized and ch...
Abstract: In the present work, three kinds of halogen-free ionic liquids (ILs) incorporating long-chain quaternary phosphonium as cations and dioctylsulfosuccinate (DOSS) as the anion were synthesized and ch...
TL;DR: In this paper, the lifetime prediction of polymer-polymer contacts is a major challenge and current design methods stemming from metal contact surfaces lack accuracy because polymers behave differently, especially regar...
Abstract: Lifetime prediction of polymer–polymer contacts is a major challenge. Current design methods stemming from metal contact surfaces lack accuracy because polymers behave differently, especially regar...
TL;DR: In this paper, four sliding bearings approved for use in shipbuilding were experimentally tested and the test results showed that the choice of the bearing type has a key effect on friction during low-speed operation.
Abstract: The bearings used in shipbuilding, hydropower, and water pumps have undergone a metamorphosis in recent decades. Because of environmental regulations, lubrication with grease or mineral oil is prohibited. Thus, the standard solutions include water-lubricated bearings with polymer bushings or sealed systems lubricated with oil. When properly designed, assembled, and operated, bearings can operate reliably for years. However, specific operating conditions, such as a low rotational speed of the shaft, may result in intensive wear and premature failure. In this study, four sliding bearings approved for use in shipbuilding were experimentally tested. The test results showed that the choice of the bearing type has a key effect on friction during low-speed operation. Some of the tested bearings had significant static friction with intense slip-stick phenomena; they should not be used in applications requiring low-speed operation.
TL;DR: In this paper, the authors conducted vibration and noise experiments under dry and wet conditions using a customized small-scale brake dynamometer and testing three friction blocks with different geometric shapes and angles.
Abstract: In this study, vibration and noise experiments are conducted under dry and wet conditions using a customized small-scale brake dynamometer and testing three friction blocks with different geometric...
TL;DR: Magnetic fluid (MF) seals have typically been used under various vacuum and gaseous low-pressure conditions as mentioned in this paper, however, there are only a few cases in which MF seals can be used in a liquid environment.
Abstract: Magnetic fluid (MF) seals have typically been used under various vacuum and gaseous low-pressure conditions. However, there are only a few cases in which MF seals can be used in a liquid environmen...
TL;DR: In this article, a generalized geometric model based on triangles is proposed to characterize spiral grooves, and the film stiffness of dry gas seal must be sufficient to keep gas film stable at high and low speed.
Abstract: The film stiffness of dry gas seal must be sufficient to keep gas film stable at high and low speed. A generalized geometric model based on triangles is proposed to characterize spiral grooves. A m...
TL;DR: The wear protection problem has become increasing prominent due to their poor wear resistance, especially in high-temperature conditions as mentioned in this paper, due to the expansion of the application range of titanium alloys.
Abstract: With the expansion of the application range of titanium alloys, the wear protection problem has become increasing prominent due to their poor wear resistance, especially in high-temperature...
TL;DR: Based on the structural features of a double-row tapered roller bearing (DTRB), a test rig for multipoint temperature measurement was built to investigate the temperature filed characteristics of DTRB as mentioned in this paper.
Abstract: Based on the structural features of a double-row tapered roller bearing (DTRB), a test rig for multipoint temperature measurement was built to investigate the temperature filed characteristics of D...
TL;DR: In this article, a single contact ball-on-disc configuration was used to study the formation of greases and showed that the film formation with greases is governed by a linear process.
Abstract: The lubricating film formation of greases has been widely studied using single contact ball-on-disc configurations. However, other than for oil, the film formation with grease is governed b...
TL;DR: In this paper, the surfaces of cold-sprayed Ti-6Al-4V (Ti64) coatings were laser irradiated with different laser powers of 50-200 W to study the effects of Nd:YAG laser surface treatment on their tribological pro...
Abstract: The surfaces of cold-sprayed Ti-6Al-4V (Ti64) coatings were laser irradiated with different laser powers of 50–200 W to study the effects of Nd:YAG laser surface treatment on their tribological pro...
TL;DR: Aged mineral-oil-based, lithium-hydroxystearate-thickened grease was collected from used axle spherical roller bearings, which were used for urban commuter trains.
Abstract: Aged mineral-oil-based, lithium-hydroxystearate-thickened grease was collected from used axle spherical roller bearings, which were used for urban commuter trains. Three types of aged greas...
TL;DR: In this paper, an increase in the hardness of the road surface has been proposed to improve rolling contact fatigue (RCF) and wear for wheels and rails. But, increasing vehicle speeds and axle loads have led to the need for an increased hardness of road surface.
Abstract: Rolling contact fatigue (RCF) and wear are inevitable problems for wheels and rails. Recently, increasing vehicle speeds and axle loads have led to the need for an increase in the hardness of the w...
TL;DR: Considering the spline friction, the dynamic model of a multidisc clutch was established in this paper that permits the calculation of the contact pressure and friction torque acting at each friction surface.
Abstract: Considering the spline friction, the dynamic model of a multidisc clutch is established that permits the calculation of the contact pressure and friction torque acting at each friction surface; the...
TL;DR: In high-speed rolling element bearings, the drag forces can be prominent and it is demonstrated in this paper that the classical models may not be appropriate for correctly estimating this drag force.
Abstract: In high-speed rolling element bearings, the drag forces can be prominent and it is demonstrated in this investigation that the classical models may not be appropriate for correctly estimating this ...
TL;DR: The theory of improving the bearing capacity of fluid lubrication with a heterogeneous slip/no-slip surface has been proposed in recent years, and the extended Reynolds equation is the main...
Abstract: The theory of improving the bearing capacity of fluid lubrication with a heterogeneous slip/no-slip surface has been proposed in recent years, and the extended Reynolds equation is the main...
TL;DR: In this article, the effect of matrix alloying of Fe on microstructure and friction and wear properties of the brake pad materia was investigated. But the effect was limited.
Abstract: Argon-gas-atomized Cu–Fe prealloyed powder was used to prepare Cu-based composites, and the effect of matrix alloying of Fe on microstructure and friction and wear properties of the brake pad mater...