1. Refer to the following maximum stress (S) versus logarithm of the number of cycles to...

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1. Refer to the following maximum stress (S) versus logarithm of the number of cycles to fatigue failure (N) for several alloys in a compression-tension stress cycling along the specimen axis. (Assume the Y-axis values are for stress amplitude) Maximum stress, S (MPa) 700 600 500 400 300 200 100 4340 steel 104 Ti-5Al-2.5Sn titanium alloy 70Cu-30Zn brass EQ21A-T6 Mg alloy 105 1045 steel Ductile cast iron 106 107 Cycles to failure, N 2014-T6 Al alloy 108 10 (A) For a safety factor of 3.5, calculate the maximum allowable load (in Newtons) to ensure that fatigue failure will not occur at 107 cycles for a cylindrical Ti-5Al-2.5Sn titanium alloy bar with a diameter of 17.0 mm. (B) Compute the maximum and minimum loads that will be applied to yield a fatigue life of 1.0 x 106 cycles for a cylindrical rod of 70Cu-30Zn brass alloy with a diameter of 12.5 mm. Assume a mean stress of 30 MPa. 1. Refer to the following maximum stress (S) versus logarithm of the number of cycles to fatigue failure (N) for several alloys in a compression-tension stress cycling along the specimen axis. (Assume the Y-axis values are for stress amplitude) Maximum stress, S (MPa) 700 600 500 400 300 200 100 4340 steel 104 Ti-5Al-2.5Sn titanium alloy 70Cu-30Zn brass EQ21A-T6 Mg alloy 105 1045 steel Ductile cast iron 106 107 Cycles to failure, N 2014-T6 Al alloy 108 10 (A) For a safety factor of 3.5, calculate the maximum allowable load (in Newtons) to ensure that fatigue failure will not occur at 107 cycles for a cylindrical Ti-5Al-2.5Sn titanium alloy bar with a diameter of 17.0 mm. (B) Compute the maximum and minimum loads that will be applied to yield a fatigue life of 1.0 x 106 cycles for a cylindrical rod of 70Cu-30Zn brass alloy with a diameter of 12.5 mm. Assume a mean stress of 30 MPa.