ABSTRACT
Measurements of contact resistance can be an efficient tool in various engineering applications. These measurements can be applied in many areas, including failure analysis, condition monitoring, and predictive maintenance of machines and apparatuses. Surface characterization is one of the most informative areas when using electrical methods. Electrical methods are used extensively in tribology. Historically, the development of electrical methods began in connection with the problem of evaluating lubrication conditions. The probe method of evaluating the surface electrical conductivity was later improved by many researchers. The preferred probe is made of solid pure gold and has a smooth spherical end with a radius of curvature equal to 1.6 mm. The probe contact material, its shape, and its dimensions have been found to insignificantly affect contact resistance, and solid gold uniquely satisfied the requirements of a readily available inert reference material having well-known properties.
