Friction

http://link.springer.com/journal/40544

List of Papers (Total 242)

The effect of different layered materials on the tribological properties of PTFE composites

Two-dimensional (2D) lamellar materials have unique molecular structures and mechanical properties, among which molybdenum disulfide (MoS2) and graphitic carbon nitride (g-C3N4) with different interaction forces served as reinforcing phase for polytetrafluoroethylene (PTFE) composites in the present study. Thermal stability, tribological and thermomechanical properties of...

Wear properties of copper and copper composites powders consolidated by high-pressure torsion

The wear characteristics of Cu and Cu-SiC composite microsize powders consolidated by cold compaction combined with sintering or high-pressure torsion (HPT) were investigated. The HPT processed (HPTed) samples with bimodal and trimodal microstructures and fine Cu grains and SiC particle sizes have superior hardness, reasonable ductility level, and high wear resistance. The wear...

Response of grease film at low speeds under pure rolling reciprocating motion

Using an optical interferometric technique, the grease film distribution under a pure rolling reciprocating motion is observed on a ball-disk test rig, to explore the transient response of grease, which is expected to fill the contact with thickener fiber and run for a long time under steady-state conditions. It is found that the reciprocating motion reduces the accumulation of...

Rapid solution for analysis of nonlinear fluid film force and dynamic behavior of a tilting-pad journal bearing-rotor system with turbulent and thermal effects

To analyze the nonlinear dynamics of a tilting-pad journal bearing (TPJB)-rotor system with high accuracy and speed, the database method (DM) is modified to rapidly determine the nonlinear fluid film force (NFFF) of a TPJB while considering turbulent and thermal effects. A high-accuracy, large-capacity NFFF database for a single pad is constructed by numerically solving the...

Molecular dynamics simulation of effects of nanoparticles on frictional heating and tribological properties at various temperatures

The temperature of a friction pair exerts considerable influence on the tribological behavior of a system. In two cases, one with and the other without Cu (copper) nanoparticles, the temperature increase in friction pairs caused by frictional heating and its tribological properties at various temperatures are studied by using the molecular dynamics approach. The results show that...

Friction of metal-matrix self-lubricating composites: Relationships among lubricant content, lubricating film coverage, and friction coefficient

Metal-matrix self-lubricating composites can exhibit excellent tribological properties owing to the release of solid lubricant from the matrix and the formation of a lubricating film on the tribosurface. The coverage of the lubricating film on a worn surface significantly influences the sliding process. However, it is difficult to quantify the film coverage owing to the thin and...

Recent advances in friction and lubrication of graphene and other 2D materials: Mechanisms and applications

Two-dimensional materials having a layered structure comprise a monolayer or multilayers of atomic thickness and ultra-low shear strength. Their high specific surface area, in-plane strength, weak layer-layer interaction, and surface chemical stability result in remarkably low friction and wear-resisting properties. Thus, 2D materials have attracted considerable attention. In...

EHD friction properties of ISO VG 320 gear oils with smooth and rough surfaces

The elastohydrodynamic (EHD) friction properties of seven ISO VG 320 gear oils including three polyalphaolefins (PAOs), three polyglycols (PG) and a mineral oil have been investigated in rolling/sliding conditions at six different temperatures and three roughnesses. Film thickness, Stribeck and traction curves have been generated using a ball-on-disc tribometer. Film thickness...

Fabrication of PTFE/Nomex fabric/phenolic composites using a layer-by-layer self-assembly method for tribology field application

Fabric composites are widely applied as self-lubricating liner for radial spherical plain bearings owing to their excellent mechanical and tribological properties. Nevertheless, the poor interfacial strength between fibers and the resin matrix limits the performance of composites utilized as tribo-materials. To overcome this drawback, a mild layer-by-layer (LbL) self-assembly...

Tribological properties of spherical and mesoporous NiAl particles as ionic liquid additives

In this study, spherical and mesoporous NiAl particles (abbreviated as sNiAl and mNiAl) were introduced as lubricant additives into two alkyl-imidazolium ionic liquids (ILs) (1-butyl-3-methylimidazolium tetrafluoroborate (LB104) and 1-butyl-3-methyl imidazolium hexafluorophosphate (LP104)) to explore their tribological properties. The sNiAl and mNiAl particles were modified in...

Investigation of parameters influencing erosive wear using DEM

The effects of several parameters on the erosive wear were studied using the discrete element method (DEM). The Finnie model was implemented using an open-source code. Regarding the time integration, the Gear algorithm was used, and to ensure the accuracy of the DEM results, a time-step sensitivity analysis was performed. The problem was modeled in two parts: first, the impact of...

Metal-containing nanomaterials as lubricant additives: State-of-the-art and future development

This review focuses on the effect of metal-containing nanomaterials on tribological performance in oil lubrication. The basic data on nanolubricants based on nanoparticles of metals, metal oxides, metal sulfides, nanocomposities, and rare-earth compounds are generalized. The influence of nanoparticle size, morphology, surface functionalization, and concentration on friction and...

Tribological properties of textured stator and PTFE-based material in travelling wave ultrasonic motors

This study fabricated textures on the stator surface of a traveling wave ultrasonic motor (USM) using laser and investigated the tribological behavior of a polytetrafluoroethylene (PTFE) composite friction material and stator. Initially, the effect of textures with different densities was tested. As the results suggested, the generation of large transfer films of PTFE composite...

Prediction of wear loss quantities of ferro-alloy coating using different machine learning algorithms

In this study, experimental wear losses under different loads and sliding distances of AISI 1020 steel surfaces coated with (wt.%) 50FeCrC-20FeW-30FeB and 70FeCrC-30FeB powder mixtures by plasma transfer arc welding were determined. The dataset comprised 99 different wear amount measurements obtained experimentally in the laboratory. The linear regression (LR), support vector...

Interplay between microstructural evolution and tribo-chemistry during dry sliding of metals

Understanding the microstructural and tribo-chemical processes during tribological loading is of utmost importance to further improve the tribological behavior of metals. In this study, the friction, wear and tribo-chemical behavior of Ni with different initial microstructures (nanocrystalline, bi-modal, coarse-grained) is investigated under dry sliding conditions. In particular...

Lubricating performances of graphene oxide and onion-like carbon as water-based lubricant additives for smooth and sand-blasted steel discs

Graphene oxide (GO) nanosheets and onion-like carbon (OLC) nanoparticles were synthesized from natural graphite powder and candle soot, respectively, and characterized by transmission electron microscopy and Raman spectroscopy. The lubricating performances of GO and OLC as lubricant additives in water were comparatively evaluated using a ball-on-disc tribometer. The effects of...

Tribological behavior of nanocarbon materials with different dimensions in aqueous systems

Due to the widespread use of nanocarbon materials (NCMs), more researchers are studying their tribological performances. In this work, the tribological behaviors of the following five types of NCMs with different geometric shapes were evaluated in a novel oil-in-water system: spherical fullerenes (C60, 0D), tubular multi-walled carbon nanotubes (MWCNT, 1D), sheet graphene oxide...

Analytical model of friction behavior during polymer scratching with conical tip

To investigate the effects of the contact geometry, interfacial friction, and substrate recovery on the behavior of polymer scratching using a conical tip, an analytical model is proposed. The normal stress acting on the contact surface between the tip and the substrate is described as a function of the included angle θ, representing the angle between two planes across the axis...

Experimental study on the tribo-chemical smoothening process between self-mated silicon carbide in a water-lubricated surface-contact reciprocating test

Silicon carbide (SiC) can be tribo-chemically smoothened during a self-mated sliding procedure in the aqueous environment. As well reported in the point-contact tests, this smoothening process works well due to the abundant water as oxidant. After this smoothening process, the tribo-surface is well polished, a closely mated tribo-gap naturally forms, and an ultra-low friction...

Sliding friction of shale rock on dry quartz sand particles

The sliding friction of rock, involving all kinds of particles at the contact surface, is relevant to many problems, ranging from those in artificial engineering to earthquake dynamics. In this work, the frictional performance of the shale rock–dry quartz sand contact was investigated using a self-developed testing device. The study showed that the coefficient of friction of the...

Comparative study of abrasion via microindentation and microscratch tests of reinforced and unreinforced lamellar cast iron

This study compares micro-abrasive wear in two kinds of grey cast iron. Classical lamellar cast iron with fully pearlitic matrix (FGL1) and lamellar micro-alloyed cast iron with phosphorus and boron (FGL2) are used. FGL2 has a fully pearlitic matrix reinforced by the hard phosphorus eutectic phase. The microstructures of these two types of iron are mechanically characterized...

Rubber plunger surface texturing for friction reduction in medical syringes

Friction is a genuine issue in the use of many medical devices involving rubbery materials such as plungers in medical syringes. This paper presents a new direction for the reduction of friction in medical syringes based on surface texturing of the rubber plunger. The specimens were prepared by casting poly(vinylsiloxane) (PVS) rubber into a pre-fabricated negative template...

Erosive wear properties of ZA-27 alloy-based nanocomposites: Influence of type, amount, and size of nanoparticle reinforcements

Metal matrix nanocomposites (MMnCs) comprise a metal matrix filled with nanosized reinforcements with physical and mechanical properties that are very different from those of the matrix. In ZA-27 alloy-based nanocomposites, the metal matrix provides ductility and toughness, while usually used ceramic reinforcements give high strength and hardness. Tested ZA-27 alloy-based...

Synthesis of water-soluble Cu nanoparticles and evaluation of their tribological properties and thermal conductivity as a water-based additive

Efficient and sustainable use of water-based lubricants is essential for energy efficiency. Therefore, the use of water-lubricated mechanical systems instead of conventional oil lubricants is extremely attractive from the viewpoint of resource conservation. In this study, water-soluble Cu nanoparticles of size approximately 3 nm were prepared at room temperature (around 25 °C...