Influence of Pre-Strain and Notching on the Fatigue Life of DD11 Low-Carbon Steel

Structural applications commonly adopt low-carbon steels, with the fatigue concept being one of the primary causes of failure. In this research, the aim was to study the fatigue behaviour of DD11 low-carbon steel, considering also specific conditions, like the effect of pre-deformation and influence of stress intensity factor. After determining the geometry and performing static tests to extrapolate the mechanical properties of the material, the fatigue behaviour of the base material was analysed, following the actual standards. Then, two conditions, a pre-strain equal to 11% and a notch, simulated with a hole and without pre-deformation, were studied. The results showed an absence of influence on the fatigue limit for the material with a pre-strain effect, and regarding the notching tests conducted, there was a low sensitivity to fatigue of the material.