Showing papers in "Tribology International in 2007"

TL;DR: In this paper, the basic mechanism of vegetable oil autoxidation is presented, along with methods used to monitor and analyse the products of oxidation, and the potential impact of such oxidation products on lubrication performance is discussed.

TL;DR: In this article, the influence of surface topography on lubricant film thickness has been investigated for the reciprocating sliding of patterned plane steel surfaces against cylindrical counterbodies under conditions of hydrodynamic lubrication.

TL;DR: In this paper, different types of friction models for sliding contacts running under different conditions are discussed from simulation and tribological points of view, and the models presented are suited to different situations, depending on the type of contact, running conditions and the behavior of interest.

TL;DR: In this paper, the authors reviewed the recent trends in materials technology and lubricant additive technology in engines and discussed the implications for boundary lubrication in the next decade and the extent to which materials and lubricants are being used in partnership in engineering systems.

TL;DR: In this article, the influence of surface roughness and hydrophobicity on the lubrication of a soft contact, consisting of a poly(dimethylsiloxane) (PDMS) sphere and a flat PDMS disk, was investigated.

TL;DR: In this article, the influence of an antiwear/extreme pressure (AW/EP) additive on the tribological performance of coconut oil was also evaluated experimentally, which brought about considerable reduction in wear with coconut oil as 2T oil.

TL;DR: In this paper, the tribological properties of ionic liquids are examined under boundary conditions, and it was found that tribochemical properties of the ionic liquid are better than those of conventional lubricants such as synthetic hydrocarbons.

TL;DR: Tribological behavior of stircast $Al-Si/SiC_p$ composites against automobile brake pad material was studied using Pin-on-Disc tribo-tester as mentioned in this paper.

TL;DR: In this paper, bearing defect is detected using the stator current analysis via Meyer wavelet in the wavelet packet structure, with energy comparison as the fault index, and the presented method is evaluated using experimental signals.

TL;DR: In this article, the tribological properties of two kinds of high temperature resistant thermoplastic composites, polyetheretherketone (PEEK) and polyetherimide (PEI), reinforced with short carbon fibre (SCF), graphite flakes, and sub-micro particles of TiO 2 and ZnS, were investigated in dry sliding conditions.

TL;DR: In this paper, the authors investigated the response of titanium to oxidation at various temperatures and timings, in terms of layer thickness, phase evolution, surface morphology, oxide layer-substrate adhesion, hardness and tribological characteristics.

TL;DR: In this article, bovine calf serum was used to simulate the body fluid, and a model solution of 0.36% NaCl solution was employed to isolate the influence of organic species (such as proteins, amino acids etc.).

TL;DR: In this paper, the tribological behavior of highly hydrogenated diamond-like carbon (DLC) coatings was evaluated in the presence of air, vacuum and dry nitrogen environments.

TL;DR: In this paper, the authors investigated the potential of surface textures to improve the friction situation of the piston/roller contact in hydraulic motors at low speed and high pressure at low pressure.

TL;DR: In this article, the fly ash particles were used as filler material for friction composites in automotive brake linings and the developed composite exhibited consistent coefficients of friction in the range of 0.35-0.4 and wear rates lower than 12-wt.

TL;DR: In this paper, the area and pressure distribution in elastic contacts between frictionless, non-adhesive surfaces are studied as a function of load and surface geometry using finite element calculations, showing that the true area of contact is proportional to load and inversely proportional to elastic modulus and the mean slope of the surface.

TL;DR: In this article, the interaction with friction modifiers (Moly dimer and Moly trimer) and anti-wear additive zinc dialkyldithiophosphate (ZDDP) under boundary lubrication condition was studied.

TL;DR: In this article, an experimental study conducted in order to determine the supply hole discharge coefficients of externally pressurized gas bearings was conducted, where air consumption and pressure distributions were measured as a function of supply pressure and air gap height for several different orifice and pocket sizes.

TL;DR: In this article, a pin-on-slip ring-type friction and wear test machine was designed and manufactured for the purpose of brush testing and the specific wear curve showed three distinct wear rate regimes, such as low, mild, and severe.

TL;DR: In this paper, a tribometer capable of measuring low friction forces and low loads at high speeds has been employed to measure the friction coefficient in a pure sliding, ball-on-flat contact in hydrodynamic lubrication conditions.

TL;DR: In this paper, a fundamental approach to the study of the wear process by considering the detachment of particles, their flow in the contact and their ejection is presented, and a numerical model is constructed in order to visualize and to accurately measure these phenomena.

TL;DR: In this paper, the effect of micro-dents depth on thin lubrication films was investigated and an experimental evidence of the micro-feature depth threshold for surface texturing applications in highly loaded non-conformal surfaces was found.

TL;DR: In this article, the tribological properties of the prepared CaF2 nanocrystals as an additive in lithium grease were evaluated with a four-ball tester and the results indicated that the anti-wear, friction reduction and extreme pressure (EP) properties were not proportional to the content of the nanocrystal but there existed a certain value.

TL;DR: In this article, the friction-wear properties of the Al 2 O 3 reinforced samples were investigated and compared to those of plain bronze-based break linings, and the hardness and density of the samples were also determined.

TL;DR: In this article, the properties of synthetic esters are investigated to improve the understanding on thier influence on base fluid overall performance, including viscosity, chemical, and film formation properties.

TL;DR: In this paper, the optimal packing structure of octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM) adsorbed on a SiO 2 (1.0) surface with a Si substrate was studied performing molecular dynamics (MD) computational simulations.

TL;DR: Experimental and numerical analysis demonstrated that slip occurred and that friction coefficient between the vessel and the catheter and the deformation of the specimen were small when the contact between the ball and the aorta occurred at a small angle, which shows that this difference of the parameter of the vessel could affect the trajectory of theCatheter.

TL;DR: In this article, the removal rate of low-friction tribofilms is studied using a distinctive testing procedure using a pin-on-reciprocating plate tribometer with lubricants comprising a combination of base oil (PAO6), zinc dialkyldithiophosphate (ZDDP) and molybdenum dialkyllithiocarbamate (MoDTC) additives.

TL;DR: In this paper, the performance of an aerostatic thrust bearing with pocketed orifice-type restrictor was analyzed and the rational dimension of this kind of bearing was obtained by analyzing the influences of the bearing's geometrical parameters on its load carrying capacity (LCC), stiffness, mass flow rate (MFR) and the maximum gas velocity (MGV).

TL;DR: In this paper, a friction model which takes temperature, speed and nominal pressure into account is developed and used with temperature calculations to simulate behavior of a wet clutch working in boundary lubrication regime.