The rusting of steel surfaces in contact

Abstract

When two hard steel surfaces are subject to relative motion under some load, it is well known that after some time a brown stain is liable to form at the common surface. A common example occurs in the case of a micrometer anvil operating on a spherical abutment, where it is periodically necessary to clean the surfaces in contact, owing to a considerable reddish brown deposit having accumulated. In engineering work the same phenomenon is found but in a more acute form. When two machined steel surfaces are held firmly in contact and at the same time are subject to vibration, it is often found on taking them apart that the surfaces have become cemented together by the production of relatively large quantities of oxide, and the individual surfaces are badly pitted and have a corroded appearance. This action goes on, it should be noted, without relative motion of the surfaces, or more correctly, without relative motion of ordinarily measurable amounts, a question which is taken up later.