This paper presents the main results of the performed experimental investigations and theoretical studies carried out to investigate the main parameters affecting facing edge tooth flank fracture damages of case carburized helical gears.
These facing edge tooth fractures were observed in different industrial gearbox applications as well as within several experimentally based research projects on the pitting load carrying capacity of case hardened gears. The crack origin of these unexpected tooth flank fractures was found to be in the area of the acute facing edge.
As a part of a special research project extensive experimental and test-accompanying investigations as well as theoretical studies were carried out to investigate the main parameters affecting facing edge tooth flank fractures.
The herein found failure mechanism is discussed in detail. Finally, recommendations to avoid gear facing edge tooth flank fractures are given in order to optimize the gear load carrying capacity.