Thermal Expansion Calculator
Calculate length change from temperature change for common engineering materials.
Results
All materials expand when heated and contract when cooled. The amount of expansion depends on the coefficient of thermal expansion (CTE), original length and temperature change. This is critical for bridges, railways, piping and any structure exposed to temperature swings. Aluminum expands nearly twice as much as steel, which matters when combining materials.
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Frequently asked questions
ΔL = 1 × 12×10⁻⁶ × 50 = 0.6 mm. Over a 100-meter bridge, that is 60 mm - which is why expansion joints are essential.
Aluminum's CTE (23 µm/m·°C) is nearly double steel's (12 µm/m·°C). A 1-meter aluminum bar expands 1.15 mm vs 0.6 mm for steel at 50°C rise. This causes stress in bimetallic assemblies.
Expansion joints provide gaps that allow the structure to expand freely. A 100 m steel bridge with 60°C annual temperature range needs joints accommodating 72 mm of movement.
A 30 m steel pipe heated 100°C expands 36 mm. Without expansion loops or bellows, this generates enormous stress - up to 240 MPa in constrained pipes, exceeding yield strength.
Yes, even 1°C changes matter. A 500 mm steel workpiece changes 6 µm per degree - significant for tight tolerances. Precision shops maintain temperature within 0.5°C of 20°C.