A wide choice of surface roughness parameters is available tocharacterize components, such as gears or bearings, with the goalof predicting the performance of such metal-to-metal contactingparts. Commonly in industry the Roughness Average (Ra)or the Mean Peak-to-Valley Height (Rz (DIN)) is chosento calculate the Specific Film Thickness Ratio for bothsuperfinished and honed surfaces. However, these two surfaceroughness parameters fail to adequately predict the performanceproperties of surfaces that are superfinished or surfaces that arehoned. In this paper, a superfinished surface is defined as aplanarized surface having a ≤0.25 mm Ra. A honed surfaceis not considered to be planarized, even with a finish of ≤0.25 mmRa. Thus, one is falsely led to predict that aplanarized surface or a honed surface, having an equivalentRa or Rz, will perform similarly.Experimentally, an isotropic planarized surface delivers superiorperformance. The following discussion utilizes another roughnessparameter, 3σ50, to further explain this phenomenon.
- Edition:
- 12
- Published:
- 10/01/2012
- Number of Pages:
- 15
- File Size:
- 1 file , 850 KB
Reviews
There are no reviews yet.