Abstract
Friction between two contacting surfaces is studied extensively. One of the known friction theories is Amontons’ law which states that the friction force is proportional to the normal force. However, Amontons’ law has been found to be invalid for elastomers. In the present study, the validity of Amontons’ law for short-cut aramid fiber reinforced elastomers is studied. Two types of fillers are used to reinforce the elastomers, namely highly dispersible silica and short-cut aramid fibers. Short-cut aramid fibers with two different surface treatments are used, namely non-reactive fibers with standard oily finish (SF-fibers) and fibers treated with an epoxy coating (EF-fibers). A pin-on-disc tribometer is used to investigate the frictional behavior of the composites in sliding contact with a granite counter surface. The results show that, after the run-in phase, Amontons’ law is valid for those composites that are reinforced by short-cut aramid fibers (without reinforcing filler, i.e., silica) if the contact pressure is below a threshold value. However, once the contact pressure exceeds this threshold value, Amontons’ law will be invalid. The threshold contact pressure of the composites containing EF-fibers is higher than of the composites containing SF-fibers. The composites that are reinforced by silica and short-cut aramid fibers do not follow Amontons’ law.
Article PDF
Similar content being viewed by others
References
Popova E, Popov V L. The research works of Coulomb and Amontons and generalized laws of friction. Friction3(2): 183–190: (2015)
Persson B N J, Sivebæk I M, Samoilov V N, Zhao K, Volokitin A I, Zhang Z Y. On the origin of Amonton’s friction law. J Phys: Condens Matter20(39): 395006: (2008)
Bowden F P, Tabor D. Friction and Lubrication of Solids. Oxford (UK): Clarendon Press, 1950.
Burton Z, Bhushan B. Hydrophobicity, adhesion, and friction properties of nanopatterned polymers and scale dependence for micro- and nanoelectromechanical systems. Nano Lett5(8): 1607–1613: (2005)
Baumberger T, Caroli C. Solid friction from stick–slip down to pinning and aging. Adv Phys55(3–4): 279–348: (2006)
Otsuki M, Matsukawa H. Systematic breakdown of Amontons’ law of friction for an elastic object locally obeying Amontons’ law. Sci Rep3: 1586: (2013)
Maegawa S, Itoigawa F, Nakamura T. Effect of normal load on friction coefficient for sliding contact between rough rubber surface and rigid smooth plane. Tribol Int92: 335–343: (2015)
Schallamach A. Friction and abrasion of rubber. Wear1(5): 384–417: (1958)
Jiménez M A, Bielsa J M, Rodríguez R, Dobón S. The influence of contact pressure on the dynamic friction coefficient in cylindrical rubber-metal contact geometries. In IUTAM Symposium on Computational Methods in Contact Mechanics. Wriggers P, Nackenhorst U, Eds. Dordrecht: Springer, 2007.
Gao J P, Luedtke W D, Gourdon D, Ruths M, Israelachvili J N, Landman U. Frictional forces and Amontons’ law: From the molecular to the macroscopic scale. J Phys Chem B108(11): 3410–3425: (2004)
Müser M H, Wenning L, Robbins M O. Simple microscopic theory of Amontons’s laws for static friction. Phys Rev Lett86(7): 1295–1298: (2001)
Vleugels N. Short fibre-reinforced elastomeric composites, fundamental routes towards improvement of the interfacial interaction of short-cut aramid fibres in a SBR compound, to improve friction and wear properties. Master’s thesis. Enschede (The Netherlands): University of Twente, 2017.
Rauline R. Composition de caoutchouc et enveloppes de pneumatiques à base de ladite composition. Patent EP 0501227, 1992.
Rodriguez N V, Masen M A, Schipper D J. A contact model for orthotropic-viscoelastic materials. Int J Mech Sci74: 91–98: (2013)
Hintze C, Boldt R, Wiessner S, Heinrich G. Influence of processing on morphology in short aramid fiber reinforced elastomer compounds. J Appl Polym Sci130(3): 1682–1690: (2013)
Khafidh M, Schipper D J, Masen M A, Vleugels N, Noordermeer J W M. Tribological behavior of short-cut aramid fiber reinforced SBR elastomers: The effect of fiber orientation. J Mech Eng Sci12(2): 3700–3711: (2018)
Khafidh M, Schipper D J, Masen M A, Vleugels N, Dierkes W K, Noordermeer J W M. Friction and wear mechanism of short-cut aramid fiber and silica reinforced elastomers. Wear428–429: 481–487: (2019)
Persson B N J. Theory of powdery rubber wear. J Phys: Condens Matter21(48): 485001: (2009)
Persson B N J. Contact mechanics for randomly rough surfaces. Surf Sci Rep61(4): 201–227: (2006)
Ronsin O, Coeyrehourcq K L. State, rate and temperature–dependent sliding friction of elastomers. Proc Roy Soc A: Math Phys Eng Sci457(2010): 1277–1294: (2001)
Chateauminois A, Fretigny C. Local friction at a sliding interface between an elastomer and a rigid spherical probe. Eur Phys J ESoft Matter27(2): 221–227: (2008)
Acknowledgements
This work is part of the Research Program of the Dutch Polymer Institute DPI, The Netherlands (Project No. #782).
Author information
Authors and Affiliations
Corresponding author
Additional information
M. KHAFIDH. He received his bachelor and master degrees in mechanical engineering from University of Diponegoro in 2012 and 2013, respectively. In 2019, he received his Ph.D. degree in tribology from University of Twente. His current position is a lecturer and researcher in Islamic University of Indonesia. His research interests include tribology of elastomeric material and biotribology.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International Li-cense, which permits use, sharing, adaptation, distribution and reproduction in any medium or for-mat, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not in-cluded in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.
To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
About this article
Cite this article
Khafidh, M., Schipper, D.J., Masen, M.A. et al. Validity of Amontons’ law for run-in short-cut aramid fiber reinforced elastomers: The effect of epoxy coated fibers. Friction 8, 613–625 (2020). https://doi.org/10.1007/s40544-019-0311-5
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s40544-019-0311-5