A solid spindle is pictured with dimensions of D = 2.0 in. and d = 1.0...

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A solid spindle is pictured with dimensions of D = 2.0 in. and d = 1.0 in. It is machined from steel in which Sut = 90 kpsi and Sy = 70 kpsi. It will operate in an environment at 100C with a reliability of 95%. The loading is one of reversed bending about a mean of zero. Given r = 0.1 in., assume the notch sensitivity factor for bending to be 0.8. a. (15 pts) Using the information provided with the attached log-log scale, create an S-N diagram assuming the steel shaft is subjected to only bending. b. (6 pts) Estimate how many cycles of life can be expected if the alternating stress is 50 kpsi. c. (9 pts) During a typical 40 seconds of operation, the cyclic bending stress was measured as recorded below. Estimate the fatigue life of the shaft in hours when operated continuously under these conditions. Bending Stress (kpsi) 60 40 20 0 -20 -40 -60 -40 sec A solid spindle is pictured with dimensions of D = 2.0 in. and d = 1.0 in. It is machined from steel in which Sut = 90 kpsi and Sy = 70 kpsi. It will operate in an environment at 100C with a reliability of 95%. The loading is one of reversed bending about a mean of zero. Given r = 0.1 in., assume the notch sensitivity factor for bending to be 0.8. a. (15 pts) Using the information provided with the attached log-log scale, create an S-N diagram assuming the steel shaft is subjected to only bending. b. (6 pts) Estimate how many cycles of life can be expected if the alternating stress is 50 kpsi. c. (9 pts) During a typical 40 seconds of operation, the cyclic bending stress was measured as recorded below. Estimate the fatigue life of the shaft in hours when operated continuously under these conditions. Bending Stress (kpsi) 60 40 20 0 -20 -40 -60 -40 sec