The fatigue data for a brass alloy are given as follows:
Stress Amplitude (MPa) -----------------Cycles to Failure
310 --------------------------------------------- 2 X 105
223 --------------------------------------------- 1 X 106
191 --------------------------------------------- 3 X 106
168 --------------------------------------------- 1 X 107
153 -------------------------------------------- 3 X 107
143 -------------------------------------------- 1 X 108
134 -------------------------------------------- 3 X 108
127 -------------------------------------------- 1 X 109
(a) Make an S-N plot using these data.
(b) Determine the fatigue strength at 5 X 105 cycles.
(c) What is the predicted useful life of this component at 200 MPa?
(d) Does this material show an ENDURANCE LIMIT.