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Thermal Expansion Calculator
Calculate a material dimensional elongation and volumetric expansion from its coefficient of thermal expansion, starting length, and a temperature change, with common material presets.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
+40.0 °C
Linear Expansion (ΔL)
Final Expanded Length (L)
Volumetric Expansion (ΔV / V₀)
β ≈ 3α for isotropic solids
How it works
- Select a common engineering material (Structural Steel, Aluminum, Copper, Concrete, Glass, or PVC) or enter a custom coefficient α.
- Enter the initial component length in meters, feet, inches, or millimeters.
- Specify the initial temperature (T₁) and final operating temperature (T₂) in °C or °F.
- The calculator computes the dimensional elongation (ΔL), final expanded length, percentage strain change, and volumetric expansion.
The formula
Linear Expansion: ΔL = α × L₀ × ΔT
Final Length: L = L₀ + ΔL = L₀ × (1 + α × ΔT)
Volumetric Expansion: ΔV = 3α × V₀ × ΔT
FAQ
What is the coefficient of thermal expansion (CTE / α)?
The linear coefficient of thermal expansion (α) is a material property that quantifies the fractional change in length per degree of temperature variation, expressed in units of 10⁻⁶ /°C (parts per million per degree Celsius).
Why do bridges, rails, and pipelines have expansion joints?
Long continuous steel rails, concrete bridge decks, and steam pipes expand and contract significantly with seasonal temperature swings. Without expansion joints or loops, constrained thermal expansion creates massive internal compressive stresses that buckle rails and crack concrete.
How do linear and volumetric thermal expansion coefficients relate?
For isotropic materials (materials with uniform physical properties in all directions), the volumetric expansion coefficient β is approximately three times the linear coefficient: β ≈ 3α.
Why does Pyrex glass withstand rapid temperature changes better than window glass?
Borosilicate (Pyrex) glass has a very low thermal expansion coefficient (approx 3.3 × 10⁻⁶ /°C) compared to standard soda-lime plate glass (9.0 × 10⁻⁶ /°C), minimizing internal thermal stresses during heating and cooling.
How we compare
| Feature | Online Tool Store | Engineering reference handbooks | Manual formula |
|---|---|---|---|
| Multi-unit length & temperature support (°C and °F) | ✓ | Partial | ✗ |
| Millimeter and micro-inch expansion readouts | ✓ | ✗ | ✗ |
| Pre-loaded material CTE property library | ✓ | ✓ | ✗ |