Sometimes simple stress formulae are not enough. The real peak stresses in hardware occurs at geometric discontinuities such as notches, holes, & filets. To get an accurate stress value, you need a stress concentration factor. This app makes that easy. Along with stress concentration factors, this app calculates the nominal and peak stresses, displays the equations, & easily prints or shares via email your result with a couple of taps.

Stress Concentration Factors 2 Features:

- Calculates the Stress Concentration Factor
- Units in Metric and English Systems
- Nominal Stress
- Peak Stress
- Designed for use on the iPhone, iPod Touch, & iPad
- Printing Capability
- Ability to email a PDF of the Geometry, Inputs, Equations, & Results

Stress Concentration Factors 2 calculates the stress concentration factors & displays the equations for 26 different geometries including:

• Single U Notch in tension
• Single U Notch in bending
• Double U Notch in tension, bending, & out of plane bending
• Single V Notch in bending
• Infinite Row of U Notches in tension
• Central Hole in tension
• Central Hole in bending, & out of plane bending
• Off Center Hole in tension & bending
• Rectangular Hole in tension
• Infinite Row of Holes in parallel & normal tension
• Square Shoulder Fillet in Tension
• Square Shoulder Fillet in Bending
• U Notch Circular Shaft in tension
• U Notch Circular Shaft bending & torsion
• Stepped Circular Shaft in tension, bending, & torsion
• Circular Shaft with a Radial Hole in tension, bending & torsion

Check out our other engineering apps by searching the App Store for:
• Pressure Vessel Pro
• Moments of Inertia
• Mohr's Circle
• Stress Intensity Factors Pro
or search J.R.Hobbs to see them all.

Ratings and Reviews

Need References


The app is easy to use. However, you need to include the source for the equations. In my work I need to verify the source of equations, otherwise it is just a black box.


Joel Hobbs
18.9 MB
Requires iOS 10.3 or later. Compatible with iPhone, iPad, and iPod touch.
Age Rating
Rated 4+
© J.R.Hobbs


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    With Family Sharing set up, up to six family members can use this app.

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