A cylindrical rod of diameter 8.0 mm (0.31 in.) fabricated from a red brass alloy (Figure...

A cylindrical rod of diameter 8.0 mm (0.31 in.) fabricated from a red brass alloy (Figure 9.41) is subjected to reversed tension–compression load cycling along its axis. If the maximum tensile and compressive loads are 7500 N (1700 lbf) and +7500 N (+1700 lbf), respectively, determine its fatigue life. Assume that the stress plotted in Figure 9.41 is the stress amplitude.

Figure 9.41 Stress magnitude S versus the logarithm of the number N of cycles to fatigue failure for red brass, an aluminum alloy, and a plain carbon steel.