7. Finite elements analysisThe finite element analysis was conducted in the region where the half-shaft is connected to the CV joint, as presented inFig. 9. It was possible to observe that a high stress concentration was localized in the region of the spline filet, which is inagreement with the observed fracture region (Fig. 3(a)) and the work of Leen et al. [16]. Comparing the effective stress valuescalculated versus the strength of the AISI/SAE 4140 steel, at the region of the spline filet, the yield strength of the half-shaft(665 MPa) was surpassed by the effective stress, which is related to a torque of 590 N m (65% of the 950 N m designrequirement). The maximum stress was observed at the face of the spline teeth, where the contact with the CV joint occurs[17,18]. The value achieved was higher than the yield strength (665 MPa). This result is corroborated by the observations ofwear on the face of the spline teeth (Fig. 7(a)) and the localized plastic deformation (Fig. 3(a) and (b)).