On the Development of a Mesoscale Friction Tester

Abstract

MEMS and NEMS devices typically have a large surface area to volume ratio. As a result, a major concern in the development of such devices is friction. Contact radii in MEMS and NEMS devices are expected to range from 10 j8 <a<10 j5 m. This regime, which generally lies between the limits of single asperity and macroscopic contact, has yet to be explored because the apparati used to characterize friction at these limits do not operate in the range of forces appropriate to these length scales. A Mesoscale Friction Tester (MFT) with smooth probe tip radii from 50 nm to 50 mm and capable of applying forces ranging from 10 nN to l mN over contact radii from 10 nm to 10 mm has been developed to address this need. With carefully planned experiments, this device has the potential to help answer unresolved questions regarding friction mechanisms in the mesoscale range.

On the modified Tabor parameter for the JKR–DMT transition in the presence of a liquid meniscus

“…A one to one correspondence between these relationships is used as a demonstration of the modified Tabor parameter. Friction experiments with the MFT [4] were used to perform the examination.…”

“…2) and its operation have been described in detail by Wang et al [4]. It consists of a sensor cantilever beam, laser diode, two dimensional position sensitive detector (PSD), and a piezo X Y Z positioning and scanning stage.…”

“…Interpreting data from devices such as the surface force apparatus (SFA) [1], interfacial force microscope (IFM) [2], the atomic force microscope (AFM) [3] and its recently introduced variant, the mesoscale friction tester (MFT) [4], requires the contact area, the relative approaching displacement, and the relationship between the pull-off force and the the two models and suggested that interactions within and outside the contact zone needed to be accounted for. Müller et al [11,12] solved this problem numerically by using a LennardJones-type potential, thereby demonstrating a continuous transition from DMT to JKR, as the Tabor parameter μ T increased.…”

Development of a Material-Testing Machine for Study of Friction: Experimental Analysis of Machine Dynamics and Friction of Rock

“…Interfacial coefficient of sliding friction (hereafter referred to simply as friction) plays a major role in many geophysical systems and engineering applications such as microelectromechanical devices [1], machining (to avoid stick-slip events) [2,3], and brakes [4]. One of the more important geophysical phenomena controlled by friction is crustal faulting and the generation of earthquakes.…”

Coefficient of Friction Measurement in the Presence of High Current Density

“…A mesoscale friction tester (MFT) was modified to allow the passage of direct current (dc) while simultaneously measuring the coefficient of friction and the parameters associated with current flow. Details of the construction and operation of the MFT are presented by Wang et al [1]. The MFT is capable of performing friction studies with contact radii that range from 10 nm to 10 μm and contact forces from 10 -6 to 10 -3 N. This force scale is beyond that of an atomic force microscope (AFM) and an interfacial force microscope (IFM) but is below that of a surface force apparatus (SFA).…”