A machinery component operates under a cyclic load conditions with the tensile stress changing with time, t, as ox = 40 (1 + (sin(21 t/7)) and shear stress changing with time as Exy = 47. (1+(sin(21 1/7)) (note that period T is the same for the tensile stress and shear stress). In every 100 cycles there are: 50 cycles with A0 = 50 MPa and Ar = 30 MPa, and 50 cycles with no = 100 MPa and Ar = 60 MPa. The material of the component has the properties with: E=205 GPa, Oy = 340 MPa, UTS=430 MPa, Ki=125 MPa:m2, and the Paris law constant A=6.8-10 MPamcycle''. The component contains a surface crack with the depth of 4 mm. Estimate by calculation the number of load Q H Edit & MAAE 4102 Engineering Materials: Strength and Fracture A. Artemev cycles within a safe service period. Assume that the crack grows along the plane normal to the direction in which the maximum tensile stress is acting. Assume that the stress intensity can be calculated as: Ky = 1.27-6-VW-a, where a is the crack depth.