Thermal Conductivity Chart
Thermal conductivity (k) of common materials — metals, insulators, fluids, and building materials.
Reference
All values at ~25 °C unless noted. Units: W/(m·K).
Metals (high k)
| Material | k (W/m·K) |
|---|---|
| Silver | 429 |
| Copper | 401 |
| Gold | 318 |
| Aluminum | 237 |
| Tungsten | 173 |
| Brass | 109 |
| Zinc | 116 |
| Nickel | 90 |
| Iron (pure) | 80 |
| Carbon steel | 43 |
| Stainless steel 304 | 16 |
| Titanium | 21.9 |
| Lead | 35 |
Semiconductors / ceramics
| Material | k (W/m·K) |
|---|---|
| Diamond | 2 200 |
| Graphene | ~5 000 |
| Silicon carbide (SiC) | 270 |
| Aluminum nitride (AlN) | 285 |
| Silicon | 148 |
| Alumina (Al₂O₃) | 30 |
| Fused silica (SiO₂) | 1.38 |
| Beryllia (BeO, toxic) | 330 |
Fluids / gases
| Fluid | k (W/m·K) |
|---|---|
| Mercury | 8.3 |
| Water (liquid) | 0.598 |
| Ethylene glycol | 0.252 |
| Engine oil | 0.145 |
| Air | 0.026 |
| Hydrogen | 0.182 |
| Helium | 0.152 |
| Argon | 0.018 |
Insulators / building
| Material | k (W/m·K) |
|---|---|
| Mineral wool | 0.034 |
| Fiberglass | 0.040 |
| Polystyrene (EPS) | 0.033 |
| Polyurethane foam | 0.024 |
| Aerogel | 0.013 |
| Wood (pine) | 0.12 |
| Drywall (gypsum) | 0.17 |
| Concrete | 1.0–1.4 |
| Brick | 0.72 |
| Glass | 0.96 |
Notes
- k increases with density but is not a simple function of it — porosity and crystalline order matter.
- Thermal paste / TIM typically sits between 0.5 and 10 W/(m·K) — but only a thin layer, so effective resistance is very low.
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