Use the graphs provided in the handout to answer the following question. (Select the option that is closest to your answer).

For full marks show all calculation handwritten work in your answer booklet. 

Handout: Figure 4  

Given data: 

Material: 2014-T6 Aluminum 

Ultimate tensile strength = 414 MPa

Stress range for rotating part: Min stress = -200 MPa, Max stress = 300 MPa

Rotation: 6 Hz ( 1 Hz = 1 cycle per second)

• How many hours would the part be expected to

  survive before failing due to fatigue

  ?