Tensile Stress Calculator Formula
Understand the math behind the tensile stress calculator. Each variable explained with a worked example.
Formulas Used
Tensile Stress
stress = f_n / areaVariables
| Variable | Description | Default |
|---|---|---|
force | Axial Tensile Force (F)(kN) | 100 |
area | Cross-Sectional Area (A)(mm^2) | 500 |
f_n | Derived value= force * 1000 | calculated |
How It Works
Direct Tensile Stress
When a member is pulled axially, the internal stress is uniformly distributed across the cross-section.
Formula
sigma = F / A
where F is the applied tensile force and A is the cross-sectional area perpendicular to the force. For members with bolt holes, use the net area (gross area minus hole areas).
Worked Example
A steel flat bar with 500 mm^2 area subjected to 100 kN tension.
- 01Convert force: 100 kN = 100,000 N
- 02sigma = 100,000 / 500 = 200 MPa
- 03This is below the 250 MPa yield strength of mild steel, so the bar is adequate.
Frequently Asked Questions
What is the difference between stress and strain?
Stress (sigma) is force per unit area (MPa). Strain (epsilon) is the ratio of deformation to original length (dimensionless). They are linked by the elastic modulus: sigma = E x epsilon.
When should I use net area instead of gross area?
When bolt holes or other openings reduce the cross-section, use the net area (gross area minus the area of holes) to compute the actual stress at the weakest section.
What does ultimate tensile strength mean?
Ultimate tensile strength (UTS) is the maximum stress a material can sustain before fracturing. It is higher than yield strength. For A36 steel, yield is 250 MPa and UTS is about 400-550 MPa.
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Open Tensile Stress Calculator