For gear systems and rlling element bearings, there are similar designations for the failures that are identified within
their respective contact surfaces. By concentrating on the contact tribo system, it is possible to go beyond the
appearance and determine the mechanisms that promote or prevent contact fatigue damage.
It is also important to identify the lubricant regime within the contact. This can be done with the modified lambda ratio.
This is aratio of the central flm thickness occurring within a contact divided by the composite roughness of the two
surfaces forming the contact, the roughness being modified to match the contact width occurring in the direction of
motion
The contact fatigue modes are identified over a range of modified lambda values. An attempt is made to describe the
failure modes and interpret the wear, fracture and/or fatigue mechanisms that lead to the failure initiation. Considering
the similarity in appearance of the gear and bearing failure modes and yet the considerably different relative surface
motions and tractions of the two contacts, this comparison helps provide insight into the basic causes of the failures and
perhaps suggests methods to avoid them.

Share on Facebook

Post on X

Follow us

Save