thermal diffusivity – A measure of how quickly a material transfers heat across a temperature difference. High thermal diffusivity can minimize the development of thermal gradients by allowing a part or parts to reach a uniform temperature quickly.
Material properties and thermal properties in particular tend to vary with temperature. Thermal diffusivity tends to vary inversely with temperature.
Symbol
On Practical Precision, thermal diffusivity is represented by the symbol D.
In other references, α, a, κ, and K may be used.
Formula
D = thermal conductivity / (density x specific heat capacity) = k / (ρ x Cp)
Units
SI: m2/s
English: ft2/s
Related articles
Selecting Materials for Kinematic Components
External references
Thermal diffusivity on Wikipedia
