AIEngineeringTool

Fatigue Safety Factor Calculator

Estimate modified Goodman safety factor for axial or bending stress.

Ultimate tensile strength: 550 MPa
Live concept view — geometry scales with the entered design condition.

Estimate modified Goodman safety factor for axial or bending stress.

Design inputs

Enter known values using the units shown. Results and the live SVG view update immediately.

PRELIMINARY RESULT

Assumed endurance limit275.00 MPa

Goodman safety factor: 1.96

Assumed endurance limit
275.00 MPa
Goodman safety factor
1.96

Calculation detail

Formula: 1 / n = σa / Se + σm / Sut

The modified Goodman line combines alternating and mean stress for a preliminary fatigue safety factor.

FORMULA VERIFICATION

Units, scope and reference

Reference: Shigley, modified Goodman relation for preliminary fatigue screening.

Internal unit basis: MPa. Outputs: factor of safety.

Valid conditions: Positive tensile stress inputs for the displayed linear relation.

Limitations: Uses a stated unmodified endurance approximation; no Marin or notch factors.