With the aim of analyzing the effect of the notch tip radius,Fig. 10 displays the maximum torque as a function of the nominal
notch tip radius. It can be observed how the influence of the notch tip radius is limited for this material, since the average maximum torque keeps close to 60 Nm regardless the radius value. A local peak in the vicinity of notch tip radius equal to 0.3 mm can be noticed and needs to be explained, as experimental scatter does not seem to the authors be the main reason.