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Required information

A part is loaded with a combination of bending, axial, and torsional stresses such that the following stresses are created at a particular location:

Bending: Completely reversed, with a maximum stress of $63$ MPa

Axial: Constant stress of $11$ MPa

Torsion: Repeated load, varying from $0$ MPa to $55$ MPa

Assume the varying stresses are in phase with each other. The part contains a notch such that $K_{f,\text{b}\text{e}\text{n}\text{d}\text{i}\text{n}\text{g}}=1\mathrm{.}4,K_{f,\text{a}\text{x}\text{i}\text{a}\text{l}}=1\mathrm{.}1,$ and $K_{f,\text{t}\text{o}\text{r}\text{s}\text{i}\text{o}\text{n}}=2\mathrm{.}0.$ The material properties are $S_y=300$MPa and $S_u=400$MPa. The completely adjusted endurance limit is found to be $S_e=200$MPa.

Estimate the number of cycles, using the Walker criterion to find the equivalent completely reversed stress. Be sure to check for yielding.

The number of cycles is $$