• Xu, Zhiqiang
• Wood, Robert J. K.
• Harvey, T. J.
• Humprheys, A.
• Wharton, Julian A.

Abstract

This study has investigated the relationship between applied interfacial electrical potentials and friction<br/>and abrasion for steel/steel contacts in alkaline aqueous-based solutions. The potential at a steel-aqueous<br/>lubricated surface is important since it determines a number of important surface properties which<br/>influence the overall friction and resistance to abrasion. The experimental approach used a pin-on-disc<br/>rig incorporating potentiostatic control of the disc between ?1.0 and +1.0V overpotential.<br/>Tests employed a load of 50N at a sliding speed of 0.03ms?1. EN 24 grade steel, equivalent to AISI<br/>4340, was used as the material for the pin and disc. Tests were conducted in electrolyte that contained<br/>electroactive species, namely octanoate ions, which could be “switched on” to the surface. Coefficient<br/>of friction measurements were carried out throughout testing and later linked to potential or current<br/>density behaviour to assess the mechanical and electrochemical interactions and its effect on wear and<br/>friction. The effects of lubricity of the adsorbed layers are discussed and used to explain the performance.

Topics

• density
• impedance spectroscopy
• surface
• steel