Investigation of bending fatigue strength of notched specimens for the development of new material-plasmanitriding combinations∗

Abstract Nowadays nitrided gears have been successfully introduced for applications such as steering gears in engines, internal gears in transmissions and other not very highly loaded applications. In future, the fast growing market for top performance gears in the vehicle industry with its high load demand, is a particularly promising expansion area. Especially here is a need for reliable fatigue data from optimized material-plasmanitriding combinations. To generate such fatigue data in a fast and cost effective way, a step by step approach with specially designed specimens and test procedures has been chosen. This paper discusses the results of the first steps and gives an outlook on the steps ahead. The first part of this investigation focuses on bending fatigue strength of the gear tooth, while other failure modes, such as pitting, will be tested in the second part of the project.