Gear Root Bending Strength: A New Multiaxial Approach to Translate the Results of Single Tooth Bending Fatigue Tests to Meshing Gears

Developing accurate design data to enable the effective use of new materials is undoubtedly an essential goal in gear industry. To speed up this process, Single Tooth Bending Fatigue (STBF) tests can be conducted. However, STBF tend overestimate material properties with respect conducted on Running Gears (RG). Therefore, it common practice a constant correction factor fkorr, value 0.9 exploit results actual gears, e.g., through ISO 6336. In paper, assumption that coefficient considered independent from material, geometry, and loading condition was questioned, combination numerical simulations multiaxial fatigue criterion, method for calculation fkorr proposed. The implementation using different geometries shows varies gears geometrical characteristics, strength, load ratio (R) set tests. particular, by applying Findley found that, same depends as well. Specifically, increases between bending torsional limits. Moreover, shown characteristics related geometry have relevant effect determining critical point (at tooth root) where fracture nucleates.