Physics
Instant, private, and free
Thermal Stress Calculator.
Calculate stress in a fully constrained uniaxial material.
Set your values
Results update as you type.
Results update automatically as you type.
Use Cases
Engineering design of constrained components
Determine the stress that will develop in a component that is rigidly fixed at both ends when it experiences a temperature change, helping to assess if the material can withstand it.
Example: A steel rail with E=200 GPa, α=12e-6 1/K, ΔT=50 K → stress = 120 MPa.
Material selection for temperature-varying environments
Compare different materials to see which produces lower thermal stress under the same constraints and temperature change, aiding in material choice.
Example: Compare aluminum vs. steel for a fixed beam with a 30 K temperature rise.
Frequently Asked Questions
- What is thermal stress?
- Thermal stress is the internal stress that develops in a material when it is fully constrained and subjected to a temperature change. It is calculated as the product of Young's modulus, the expansion coefficient, and the temperature change.
- How is thermal stress calculated?
- The calculator uses the formula: Thermal Stress = Young's Modulus × Expansion Coefficient × Temperature Change. This assumes the material is fully constrained and cannot expand or contract freely.
- What units should I use?
- Enter Young's modulus in pascals (Pa), expansion coefficient in per kelvin (1/K), and temperature change in kelvin (K). The result will be in pascals (Pa).
Tips & Common Mistakes
Tips
- Ensure the material is truly fully constrained; if it can expand partially, the stress will be lower.
- Use consistent units: convert all inputs to SI units (Pa, 1/K, K) before calculating.
- Remember that thermal stress is independent of the material's length or cross-sectional area.
- For temperature changes, use the difference between final and initial temperatures in kelvin.
Common Mistakes to Avoid
- Forgetting to convert temperature change from Celsius to Kelvin; the difference is the same, but ensure you use the correct value.
- Using the expansion coefficient in per °C instead of per K; they are numerically equal for differences, but be consistent.
- Assuming the material is not fully constrained when it is, leading to an underestimation of stress.
Last updated: August 13, 2026