Fatigue properties of notched specimens made of FeP04 steel

Fatigue properties of specimens with different notches made of FeP04 steel are presented. The specimens are characterized by double symmetric lateral notches with radius of the notch root ranging from ρ = 0.2 to 10 mm. An MTS 809 servohydraulic device was used for the tests. All fatigue tests were performed under force control by imposing a constant value of the nominal load ratio (R = 0) and a load amplitude P _a  = 6 kN for the notch root ρ = 0.2 mm and 7 kN for the notch roots ρ = 1.25, 2.5 and 10 mm. The test frequency varied from 13 to 15 Hz. During the tests performed under constant loading, we observe the fatigue weakening of the material and an increase in strain.