Design a shaft for a fatigue test (rotating beam bending) under the following conditions.
• The shaft must be able to withstand a completely reversed bending moment (depending on the load between 20 and 50 kg hanging at load point shown in Fig.1) and fail at 5 x 104 cycles.
• The students can select the material from the list available in “Shigley’s Mechanical Engineering Design” textbook. If the students use other materials other than that provided in the textbook, the printout of the material properties from the reliable source should be attached.
• The shaft must contain at least one feature where stress concentration is high (e.g. hole, keyseat, shoulder (fillet), retaining ring groove, etc.) in the design zone.
• The supports and load point are shown in Fig. 1 below.