PSI - Issue 80

Francesco Manni et al. / Procedia Structural Integrity 80 (2026) 177–186 Francesco Manni/ Structural Integrity Procedia 00 (2019) 000–000

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4.1. Analysis of the first configuration In the first configuration, as shown in Fig. 6. Contact status of the first meshing configuration. , contact has been imposed on the upper part of the tooth of the gear under examination in order to maximize the bending moment acting on it. The overload condition is applied and an abnormal deformation has been induced, causing the contact to extend to the next tooth, see Fig. 6. As a result, the load has been distributed across two contacts, significantly reducing the severity of the impact of the overload. In fact, the result shows that the tooth undergoes plastic deformation, but only in the outermost area, where the contact is imposed. Despite this, the plastic deformation remains too limited to cause any noticeable change in the residual stresses imposed by nitriding, see Fig. 7. Therefore, this configuration has been considered not to be the main responsible of the gear failure.

Fig. 6. Contact status of the first meshing configuration.

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Fig. 7. Plastic strain after the application of the overload, detail of a tooth section.

4.2. Analysis of the second configuration Fig. 8 illustrates the second configuration, which has been set up to maximize the bending moment while avoiding overload-induced contact with the adjacent tooth. This setup has been intended to concentrate the load as much as