Thermal conductivity is the propensity for any material to transfer heat from one point to another. Of course for heat to "flow," it is necessary for a difference of temperature to exist within a continuous section of the material.
Thermal conductivity is analogous to electrical conductivity. Similarly, thermal resistance is the inverse of thermal conductivity as electrical resistance is the inverse of electrical conductivity.
Coefficient of expansion is the rate at which a material will grow in length with an increase in temperature. Most material grow in a fairly linear fashion, particularly within a defined range of temperatures. A positive coefficient of expansion indicates that the material gets longer as its temperature increases. Most metals are like that. Ice is a well-known example of a negative coefficient of expansion, since it contracts in length with increasing temperature
(in other words, ice expands as it gets colder).
|Specific Thermal Conductivityb
|Diamond (room temp)||6.299|
|Epoxy (thermally conductive)||0.008|
|Silicon (0.0025 Ω-cm)||1.457|
|Silicon Dioxide (amorphous)||0.014|
|Silicon Dioxide (quartz, a-axis)||0.059|
|Silicon Dioxide (quartz, c-axis)||0.11|
|Silicon Nitride||0.16 - 0.33|
|Stainless Steel (321)||0.146|
|Stainless Steel (410)||0.240|
|Steel (low carbon)||0.669|
a: Approximate values from 0 °C to 100 °C
b: Thermal conductivity divided by specific gravity
(introduced by Dr. Carl Zweben & K.A. Schmidt)