Science & Engineering

Thermal Conductivity Chart

Thermal conductivity (k) of common materials — metals, insulators, fluids, and building materials.

Updated Apr 19, 2026 2 min read

All values at ~25 °C unless noted. Units: W/(m·K).

Metals (high k)

Materialk (W/m·K)
Silver429
Copper401
Gold318
Aluminum237
Tungsten173
Brass109
Zinc116
Nickel90
Iron (pure)80
Carbon steel43
Stainless steel 30416
Titanium21.9
Lead35

Semiconductors / ceramics

Materialk (W/m·K)
Diamond2 200
Graphene~5 000
Silicon carbide (SiC)270
Aluminum nitride (AlN)285
Silicon148
Alumina (Al₂O₃)30
Fused silica (SiO₂)1.38
Beryllia (BeO, toxic)330

Fluids / gases

Fluidk (W/m·K)
Mercury8.3
Water (liquid)0.598
Ethylene glycol0.252
Engine oil0.145
Air0.026
Hydrogen0.182
Helium0.152
Argon0.018

Insulators / building

Materialk (W/m·K)
Mineral wool0.034
Fiberglass0.040
Polystyrene (EPS)0.033
Polyurethane foam0.024
Aerogel0.013
Wood (pine)0.12
Drywall (gypsum)0.17
Concrete1.0–1.4
Brick0.72
Glass0.96

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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