Mechanics

Example 1 The values of fatigue life at various stress amplitudes for specimens of an aluminium alloy are given in table below. A component made of this alloy was subjected to reversed cyclic loading in a sequence involving three stages: 20 104 at 210 MPa, 10 104 at 240 MPa, and 1.2 104 at 300 MPa, after which it remained unbroken. Determine the number of additional cycles this component would withstand at 270 MPa prior to failure. [MPa] 210 240 270 300 330 Nf [cycles] 100 104 40 104 15 104 5 104 2 104