Thermal Expansion Calculator

Calculate ΔL = α · L₀ · ΔT. Know when your weld cracks.

Input Parameters

Load Preset Scenario

The Physics Behind the Numbers

Sparks flying from metal forging at a foundry, capturing the moment thermal stress transforms raw alloy into engineered form

When I weld a 1960s racing car chassis, I am not joining metal. I am managing a thermal event. Heat expands steel at 12 micrometers per meter per degree Celsius. Cool it unevenly, and residual stress fractures the joint from within.

ΔL = α · L₀ · ΔT

Where:
• ΔL = change in length (mm)
• α = linear coefficient of thermal expansion (µm/m·°C)
• L₀ = original length (m)
• ΔT = temperature change (°C)

Material α (µm/m·°C) Critical Note
Carbon Steel 12 Standard chassis material. Predictable, forgiving.
Aluminum 6061-T6 23 Nearly double steel's expansion. Requires controlled cooling.
Titanium Ti-6Al-4V 8.6 Aerospace grade. Low expansion, high yield strength.
Invar 36 1.2 Near-zero expansion alloy. Used in precision instruments.
Source: Wikidata Q45760 (coefficient of thermal expansion).
Values verified against ASM Handbook Vol. 1: Properties and Selection of Metals.
Machine-readable data: thermal-expansion-data.json
Image: Pexels (royalty-free, no attribution required).