Windchill Risk and Reliability Desktop Help > Windchill Prediction > Part Parameters Required for Predictions > Mechanical Model > Entering Threaded Fasteners > Endurance Limits
Endurance Limits
The table below displays common endurance limits for various threaded fasteners.
Material Grade or Class
Size Range
Endurance Limit
SAE 5
1/4 to 1 inch
18.6 kpsi
SAE 5
1-1/8 to 1-1/2 inch
16.3 kpsi
SAE 7
1/4 to 1-1/2 inch
20.6 kpsi
SAE 8
1/4 to 1-1/2 inch
23.2 kpsi
ISO 8.8
M16 to M36
129 Mpa
ISO 9.8
M1.6 to M16
140 Mpa
ISO 10.9
M5 to M36
163 Mpa
ISO 12.9
M1.6 to M36
190 Mpa
Metric M16, CL 8.8
M16
10.2 ksi
Metric M14 x 1.5
M14 x 1.5
7.1 to 11.4 ksi
SAE J429, GR 8
---
18 ksi
Metric CL 10.9
M12 x 1.25
8 ksi
M10, grade 12.9
---
6.9 to 10.7 ksi
Formulas for estimating the endurance limits of S-N Test Specimens are:
• For steels with tensile strength <= 200 kpsi, Endurance Limit = 0.5 * Tensile Strength.
• For steels with tensile strength > 200 kpsi, Endurance Limit = 100 kpsi.
• For wrought aluminum alloys, Endurance Limit = 0.4 * Tensile Strength.
• For cast aluminum alloys, Endurance Limit = 0.3 * Tensile Strength.
The endurance limit of nonferrous alloys is taken to occur at approximately 1E8 cycles.
Entering Threaded Fasteners