Development of low friction surfaces has become an important issue for the development of reliable devices with moving components. The common way to measure nanofriction is to use a sharp tip sliding on a sample surface. High contact pressure at the tip apex often induces plowing, which leads to an additional resistance to the tip motion so that the measured friction data contain contributions from multiple sources. An understanding and quantification of the plowing phenomenon would allow us to avoid plowing, if possible, and to deduct the plowing contribution to friction in order to obtain the interfacial friction data in cases that plowing is unavoidable. This paper reports our study of plowing effects, using diamond tips and several substrate materials, with the aim to quantify the plowing phenomenon. Using an energy approach, the additional work done by the tip in order to overcome the plowing resistance is found to be proportional to volume of displaced material.
Extended Abstract for International Tribology Conference