A spur gear transmission includes a stepped steel shaft as shown in thefigure. The applied torque induces a constant torsion shear stress on thesurface of 120 MPa. The applied bending moment induces an alternatingbending stress on the surface with a magnitude of 100 MPa. These stressvalues include the effect of the stress concentration.r°C)MMTTDdThe steel has an ultimate strength of 552 MPa and a yield strength of 434MPa. All of the surfaces are machined, and the hardness is 160 Bhn. Theoperating temperature stays below 300 °F.A. Estimate the endurance limit for this steel with a reliability of 50%.The shaft diameter is in the range resulting in a gradient factor, CG =0.9. The bending load factor, CL = 1, is appropriate for this state ofbiaxial stress.B. Given the defined state of stress and the calculated endurance limit,estimate the safety factor.

Answered: Image /qna-images/answer/0fa8ad7b-e143-474a-8f7f-15d6069429bb.jpg

Answered: cays below 300 °F. nce limit for this…

cays below 300 °F. nce limit for this steel with a reliability in the range resulting in a gradient fac d factor, C_ = 1, is appropriate for this

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter8: Applications Of Plane Stress (pressure Vessels, Beams, And Combined Loadings)

Section: Chapter Questions

Problem 8.5.32P

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