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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Fig. 4. Residual stress trend as a function of depth.

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Fig. 5. Residual stress due to nitriding, detail of a tooth section.

4. FEM analysis Several FE simulations have been carried out using the commercial software MarcMentat. Initially, two specific meshing configurations have been selected, as they have been considered the most likely to induce significant plastic deformation in the gear components. Based on a visual analysis of the fracture surface, the failure resulted from fatigue loading has been hypothesized to be associated with tooth bending during meshing. Consequently, the initial focus has been on loading conditions that could replicate this type of stress. In particular, meshing scenarios have been investigated that would maximize the bending moment at the critical location where crack initiation is located. Two different contact configurations have been considered. The first has been designed to maximize the bending moment, and thus the tensile stresses, in the root area of the tooth. The second configuration has ensured contact between only two teeth, concentrating the entire load on a single contact pair to further amplify local stress effects. In addition, a final simulation has been performed under overload conditions, modelling the complete meshing process to capture the overall stress state within the component.