Question

A cylindrical 1045 steel bar is subjected to repeated compression-tension stress cycling along its axis. If the load amplitude is 22,000 N (4950 lbf), compute the minimum allowable bar diameter to ensure that fatigue failure will not occur. Assume a factor of safety of 2.0

Answer 1

13.4 mm

Step-by-step explanation:

Given data :

Load amplitude ( F ) = 22,000 N

factor of safety ( N )= 2.0

Take ( Fatigue limit stress amplitude for this alloy ) б = 310 MPa

calculate the minimum allowable bar diameter to ensure that fatigue failure will not occur

minimum allowable bar diameter = 13.4 * 10^-3 m ≈ 13.4 mm

attached below is a detailed solution