Numerical contact analysis of transversely isotropic coatings

Solid lubricant coatings are commonly used to reduce friction and wear in c ontacting surfaces. In this work, the contact characteristics of transverse ly isotropic coatings are investigated using the finite element method. A t wo-dimensional finite element model is presented for determining the maximu m surface pressure, contact area, and approach distance for the line contac t of coated cylinders. Using the model, contact behavior is evaluated over a diverse range of transversely isotropic coating materials and thicknesses . Verified numerical results are obtained at 297 distinct operating conditi ons by varying coating material (SiC, NbSe2, Graphite, Al2O3, Cadnium, Coba lt, GaS. GaSe2, InSe2, MoS2), coating thickness (10-100 mu m), normal load (200-20,000 N/m), and cylinder radii (0.005-0.015 m). Based on the finite e lement results, numerical expressions are derived as a function of a transv ersely isotropic coating parameter, zeta, for the maximum surface pressure, contact length, and approach distance. The importance of these expressions , as related to design and the selection of materials for reducing wear in contacting surfaces, is subsequently discussed. (C) 1999 Elsevier Science S .A. All rights reserved.