Roughness amplitude reduction under non-newtonian EHL conditions

The influence of surface roughness on the performance of bearings and gears operating under EHL conditions has become increasingly important over the last decade, as the average film thickness decreased due to various influences. Surface features can reduce the minimum film thickness and thus increase the wear. They can also increase the temperature and the pressure fluctuations, which directly affects the component life. A discussion on the first contribution to the extension of the roughness amplitude reduction for EHL point contacts including non-Newtonian effects covers the general Contact Mechanics equations and the numerical techniques; numerical results for pressure and film thickness for isotropic harmonic roughness passing through a circular EHL contact; and the amplitude reduction of an isotropic harmonic pattern using the Ree-Eyring model and comparison with the one obtained using the traditional Newtonian model with the Roelands pressure-viscosity relation. This is an abstract of a paper presented at the World Tribology Congress III (Washington, DC 9/12-16/2005).