Question

P4. A 1.2" (30 mm) diameter shaft made of 1030 CD has two critical points. The torque at both points is 4 in-kips (450,000 N-mm), and the material has a tensile strength of 76 ksi (520 MPa) and an endurance limit of 23 ksi (157 MPa). .Point 1 is where the moment is the maximum, 2.5 in-kips (282,000 N-mm) and the stress concentration factors are 1.0. Point 2 is the location ofa groove where K-1.57 and Kris 1.34 where the moment is 2 in-kips (225,000 N-mm) . a) What are the factors of safety, n, using the DE-Goodman model, at both points? b) Where is the shaft more likely to break?

Answer 1