scholarly journals AN EXPERIMENTAL STUDY ON THIRD-BODY PARTICLE TRANSPORT IN SLIDING CONTACT

2021 ◽  
Vol 19 (1) ◽  
pp. 001
Author(s):  
Qiang Li ◽  
Iakov A. Lyashenko ◽  
Jasminka Starcevic

An experiment is designed to study the third-body particle transport in a rough contact. To study the influence of particles in a pure form, it is assured that the first bodies have no contact and the sliding is very slow, so that the process can be considered as quasistatic. An example of sliding contact of a 3D printed “rough body” on small spheres artificially located on a rubber layer is presented. The trajectory of particles during the sliding is captured for studying their movement and the correlation to the fluctuation of normal and tangential force.

Author(s):  
David Richard ◽  
Mathieu Renouf ◽  
Yves Berthier ◽  
Ivan Iordanoff

The objective of this paper is to highlight the influence of the rheology of a third body in dry sliding contact conditions. It has been shown that the local cohesion of the third body can create an asymmetric dissipative field through its thickness. The present study puts forward the consequences from a thermal point of view, overcoming the inherent experimental difficulties at this microscopic scale.


2019 ◽  
Vol 68 (1) ◽  
Author(s):  
Narinder Singla ◽  
Jean-François Brunel ◽  
Alexandre Mège-Revil ◽  
Haytam Kasem ◽  
Yannick Desplanques

Author(s):  
R. A. Waikar ◽  
Y. B. Guo

A white layer on a machined surface is often produced at abusive machining conditions. However, the effect of white layer on frictional and wear performance has received little attention. This study has shown that the existence of a turned white layer slightly decreases the coefficient of friction (COF), while a ground white layer significantly increases COF at dry conditions. At lubricated conditions, the turned white layer only slightly increases COF while the ground white layer slightly reduces it. The third body wear debris may act as solid lubricants leading to reduced friction.


2008 ◽  
Vol 130 (3) ◽  
Author(s):  
David Richard ◽  
Ivan Iordanoff ◽  
Mathieu Renouf ◽  
Yves Berthier

When the thermal aspect of sliding contacts is investigated, few models take into account the presence of a third body at the contact interface. Moreover, when the presence of the third body is considered, its rheology is neglected. For this reason, the thermal study of such contact configuration is not fully understood and relies on strong hypothesis or even important simplifications. To fill this lack of knowledge, a thermal model has been developed embedded in a discrete element scheme. Such investigations highlight the key role played by both thermal and mechanical properties of the contact elements. If the third body rheology can affect the localization of the heat generation leading to important thermal asymmetries, the diffusive nature of the first bodies can also strongly control the phenomenon and accentuate or diminish the initial differences of surfaces temperature for the contacting volumes. The goal of this paper is to bring information or complete existing theories (Blok, H. A., 1937, “Theoretical Study of Temperature Rise at Surface at Actual Contact Under Oilness Lubricating Conditions,” I. Mech. E. Conf. Publ., 2, pp. 222–235;Ryhming, I. L., 1979, “On Temperature and Heat Source Distributions in Sliding Contact Problems,” Acta Mech., 32, pp. 261–274;Dragon-Louiset, M., and Stolz, C., 1999, “Approche Thermodynamique des Phénomenès liés à l’Usure de Contact,” Acad. Sci. Paris, C. R., 327, pp. 1275–1280) but also to bring a new point of view on the differences observed in the past between the numerical predictions and experimental measurements.


1999 ◽  
Vol 121 (2) ◽  
pp. 403-407 ◽  
Author(s):  
Mohamed El Mansori ◽  
Marjorie Schmitt ◽  
Daniel Paulmier

This paper completes previous studies concerning the mechanisms governing friction and wear of a steel/graphite couple under an external applied magnetic field. Friction tests were performed in a controlled chamber with a magnetised steel pin sliding against a graphite disk exposed to oxygen, argon, and vacuum environments. Wear debris and friction tracks generated by reactions with the gases after sliding, with and without magnetic field, were identified ex situ by scanning electron microscopy and energy-dispersive X-ray analysis. It shows that the magnetic field modifies the third body behavior which depends on the gases surrounding the contact; this governs the friction state, the type of graphite wear (fatigue or abrasive wear), and the surface reactivity.


2021 ◽  
Vol 133 (3) ◽  
Author(s):  
Marilena Di Carlo ◽  
Simão da Graça Marto ◽  
Massimiliano Vasile

AbstractThis paper presents a collection of analytical formulae that can be used in the long-term propagation of the motion of a spacecraft subject to low-thrust acceleration and orbital perturbations. The paper considers accelerations due to: a low-thrust profile following an inverse square law, gravity perturbations due to the central body gravity field and the third-body gravitational perturbation. The analytical formulae are expressed in terms of non-singular equinoctial elements. The formulae for the third-body gravitational perturbation have been obtained starting from equations for the third-body potential already available in the literature. However, the final analytical formulae for the variation of the equinoctial orbital elements are a novel derivation. The results are validated, for different orbital regimes, using high-precision numerical orbit propagators.


Sign in / Sign up

Export Citation Format

Share Document