Dry Gross Fretting of Rough Surfaces

The 2D profile was analysed earlier. Standards ISO 4287 and ISO 11562 define the roughness profile, waviness profile, the primary profile and their parameters. The mean line is determined by fitting a least squares line through the profile. The roughness profile is derived from the primary profile by retaining the short-wave component. The waviness profile contains long wavelengths.

Fretting can be defined as a relative motion with a very small amplitude between two oscillating surfaces. Depending on the applied normal load and relative displacements, various sliding regimes can be identified: a partial slip and a gross slip. A fretting damage type is dependent on sliding regimes, and it leads to cracking (fretting fatigue) under a partial slip (lower amplitude) and wear damage under a gross slip (higher amplitude).

The typical operating parameters are amplitude, normal load and frequency. In previous research reported in [1], it was found that the wear volume was proportional to the amplitude to displacement; however, the effect of this amplitude on the coefficient of friction was marginal.