Finite element fatigue analysis of Notched F55 super duplex stainless steel

In the current research, notch fatigue investigations are carried out for F55 super duplex grade stainless steel, using Finite Element technique. Notches of different geometric parameters i.e. width (W) and depth (D), are created on the coupons and the fatigue life (L), stress and strain are found at different forces using ANSYS package. The fatigue results are analysed using Response Surface Methodology to arrive at optimal conditions and to obtain the regression equation with respect to notch parameters and force. It is found that infinite fatigue life is yielded for all the magnitudes of the applied force in the case of un-notched specimen. However, there was a significant decrement in fatigue life in case of the notched counterparts. The notch depth was found to have a more significant impact on fatigue life reduction than the notch width, owing to localized stress concentration at the notch root. The optimal parameters condition in the current research is found to be notch width at 0.7475 mm, notch depth at 0.5 mm and applied force at 1000N. The fatigue life is found to be infinite (>10 6 ) cycles at these parameters through the regression equation as well as the confirmation experiment undertaken employing FEM.