Thermophysical Properties Research Laboratory, Inc.
Phone : 765-463-1581
Thermal Conductivity

Thermal conductivity determines the quantity of heat which flows in unit time through unit area of a layer of the substance of unit thickness with unit difference of temperature between its faces.

TPRL provides four methods to measure conductivity.

The most common is to measure the thermal diffusivity with the laser flash (ASTM E1461), specific heat (ASTME 1269), and density of the material. The thermal conductivity is a calculation product of these values.


This method can be used for conducting solids and some viscous liquids over a temperature range of liquid nitrogen to 2225°C.

For insulating solids, the step heat apparatus is used to measure the thermal conductivity. This method runs over a temperature range of -90°C to 1000°C.

For liquids, gels, and powders, the heated probe is used.

For electrically conducting solids that are in a strip, rod, or tube form that is 10 inches in length,
the multi-property apparatus can be used.
However, generally the laser flash is the preferred technique for these solid materials.

Still not sure what is the best testing method for your material? Use our Testing Method Selector Tool to help you decide.

Thermophysical Properties Measured

Thermal Conductivity

Thermal Diffusivity

Specific Heat

Thermal Expansion

Electrical Resistivity


Thermal Gravimetric Analysis & Simultaneous Thermal Analysis


ASTM Methods

Sample Sizes & Definitions

Test Selector Tool

Copyright 2021 TPRL, Inc.
3080 Kent Avenue
West Lafayette, IN 47906
Last updated 5/21/2021