3. Influence of parameters

The classification of lubrication regimes according to average lubricant film thickness, proposed in Section 1, is conceptually very appealing. However, it has two major drawbacks limiting its scope for industrial applications:

• the parameter used is difficult to measure. In fact, measuring the thickness of the lubricant film in a contact requires very specific instrumentation because of the limited accessibility, the order of magnitude of the dimensions, and the need to extract an average value (see note in subsection 2.2 on mixed lubrication);

• contact operating parameters (normal force, speed, materials, microgeometries, etc.) are not explained.

This section describes the influence of the main contact technology parameters on the establishment of the mixed lubrication regime....