Mirrorlike Finishing of Precision Rollers and Changes on the Roller Surfaces Caused by Loaded Running.

Abstract

Recent progress in manufacturing techniques makes it possible to produce gears with mirrorlike tooth surfaces. This investigation is conducted to reexamine the changes in the contact surfaces and the surface durability of rollers which simulate the tooth surface of gears because the rollers used in earlier experiments are not ideally finished. A new bufting machine is designed and made by the authors and a method for producing precision mirrorlike-finish rollers with a roughness of about 0.02 μm Rmax is presented. Using these rollers, endurance tests under heavy loads are conducted with five kinds of lubricating oils including traction oils. Almost full EHL oi1 film is formed between the mirrorlike-finish rollers soon after start of running. An interesting change in the contact surfaces is found when an oil with a high traction coefficient is used. It is estimated that the change is the result of irregular plastic deformation which is caused by irregular soldification of the oil film between the contacting rollers.