An extension of the Hertz theory for 2D coated components

The classic Hertz theory is not applicable when components in contact have coatings. An extension of the Hertz theory is presented in this paper for contact between coated cylinders. The concise form of the Hertz theory is adopted to express the maximum contact pressure and contact half-width in terms of applied load, equivalent radius, and an extended equivalent modulus. According to the form of an analytically known frequency response function, the extended equivalent modulus due to the presence of the coating is a function of Youngs moduli and Poissons ratios of the coating and the substrate, the coating thickness, and a parameter, which is obtained through substantial numerical simulation. This extension is easy to use and yields accurate predictions of the maximum contact pressure and contact half-width.