To lower the friction coefficient and increase the wear resistance of epoxy, nanoparticles of zinc oxide and polytetrafluoroethylene (PTFE) were added in small volume percents to an epoxy matrix. Tribological testing of the samples in this study was completed on a linear reciprocating tribometer with a 250 N normal load and a 50.8 mm/s sliding speed. Several samples were made and tested followi...

Mechanical engineering often uses fluid lubrication to limit friction. Even in the presence of a lubricant, metallic contact between the sliding surfaces may readily occur. In running-in, the oil film thickness can be so thin that contact arises at the summit of asperities, thus, increasing both the friction coefficient and wear. Such regimes are the so-called mixed or boundary lubrication. In ...

Sliding bearings with low coefficient of friction enable the base isolation system with longer natural period than previous ones and to be effective even for small to medium earthquakes. This paper introduces the sliding bearings with low coefficient of friction, which is almost under 0.03. It is shown that newly developed materials for the sliding bearings contribute to reduce coefficient of f...

This article investigates the effect of contact ageing on fretting damage of an epoxy-based cathodic electro-deposited coating for use on automotive seat slide tracks (made of cold-rolled high strength steel). Static normal load was induced at the contact between the coating and an AISI52100 ball for a certain duration. It was identified that plastically deformed contact area increased logarith...

PURPOSE OF THE STUDY The wear of articular surfaces is considered one of the most important factors limiting the life of total hip arthroplasty (THA). It is assumed that the particles released from the surface of a softer material induce a complex inflammatory response, which will eventually result in osteolysis and aseptic loosening. Implant wear is related to a friction coefficient which depe...

Internal friction in concentrated alloys at kHz frequencies and at temperatures from 120 3 0 0 K has been studied in alpha-and beta-brasses as a function of grain size, temperature and pre-strain, and a statistical model has been proposed to account for the observations.

A model that predicts the static friction for elastic-plastic contact of rough surfaces is presented. The model incorporates the results of accurate finite element analyses for the elastic-plastic contact, adhesion and sliding inception of a single asperity in a statistical representation of surface roughness. The model shows strong effect of the external force and nominal contact area on the s...

This paper investigates the friction coefficient of a moving liquid marble, a small liquid droplet coated with hydrophobic powder and floating on another liquid surface. A floating marble can easily move across water surface due to the low friction, allowing for the transport of aqueous solutions with minimal energy input. However, the motion of a floating marble has yet to be systematically ch...

Time-stepping methods using impulse-velocity approaches are guaranteed to have a solution for any friction coefficient, but they may have nonconvex solution sets. We present an example of a configuration with a nonconvex solution set for any nonzero value of the friction coefficient. We construct an iterative algorithm that solves convex subproblems and that is guaranteed, for sufficiently smal...