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Rp_ Studying the Effect of Notch Depth and Position on Fatigue Properties pdf

The present work investigates the effects of notch depth, location and load magnitude on fatigue life and thermal behavior of a rotating cantilever beam made of low carbon steel (ST37-2) by applying fully reversed load, zero mean stress. During the fatigue test, the temperature variation on the testing specimens was monitored using an IR camera, particularly at two specific points (edge and notch). By the way studying the effects of the above parameters on the area of sudden fracture surface and hardness of two points on fractured surface (point on propagation region and other point on the sudden fracture region) was done. Numerically, finite element simulation for the fatigue test was implemented using ANSYS Workbench 15.0, where the ANSYS input data was based on an experimental S/N curve.
From the results, the notch location can change the fracture position from the notch to the edge position. Furthermore, the fatigue life is increased to its maximum value through shifting the notch by the maximum ratio: experimentally more than (75) % and numerically more than (73) %. On the other hand, the shifting of notch away from the edge position produces a decreasing the area of sudden fracture surface as well as the hardness of the fracture surface till the transforming point. The comparison between the experimental and numerical results shows apparent agreement in behavior, where the ANSYS model based on experimental S/N curve provides a good prediction for fatigue life. Temperature variation at different points on the specimens offers a practical way to predict the fracture position before it happens.