a) A bar of normalized AISI 4130 is subjected to a steady torsional stress of 103 MPa, an alternating torsional stress of 69 MPa, and alternating bending stress of 83 MPa. It has an endurance limit of 276 MPa. Using Gerber and ASME-elliptic criteria, find the safety factors guarding against a fatigue failure and the expected life of the part. Analyse your results. b) A bar of 25 mm diameter cold-drawn SAE 1045 steel is loaded in rotating bending. Determine its endurance limit or strength.

a) A bar of normalized AISI 4130 is subjected to a steady torsional stress of 103 MPa, an alternating torsional stress of 69 MPa, and alternating bending stress of 83 MPa. It has an endurance limit of 276 MPa. Using Gerber and ASME-elliptic criteria, find the safety factors guarding against a fatigue failure and the expected life of the part. Analyse your results. b) A bar of 25 mm diameter cold-drawn SAE 1045 steel is loaded in rotating bending. Determine its endurance limit or strength.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter1: Tension, Compression, And Shear

Section: Chapter Questions

Problem 1.6.5P: An aluminum bar has length L = 6 ft and diameter d = 1.375 in. The stress-strain curse for the...

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