Thermal Conductivity

Thermal conductivity is a physical property of materials that describes their ability to conduct heat. It is the measure of the rate at which heat energy is transferred through a material per unit on time, per unit area, and per unit temperature difference. Materials with high thermal conductivity can efficiently conduct heat, while those with low thermal conductivity are poor heat conductors.

TRUSTED BY ENGINEERS FROM

Thermal Conductivity

Written by Dr. Bhargav Raval | Updated: September 10, 2025

Thermal Conductivity

Several methods for measuring thermal conductivity involve applying a heat source to a sample of the material and measuring the temperature gradient across the sample. The resulting data can be used to calculate the material’s thermal conductivity.

Some of the most common methods include:

Guarded Hot Plate Method: This steady-state method involves applying a constant temperature difference across a material and measuring the heat flux through the material. It is considered the most accurate and reliable, but it is also the most complex and expensive.
Transient Hot Wire Method: This is a transient method that involves applying a short heat pulse to a wire embedded in the material and measuring the time it takes for the heat to dissipate through the material.

Video 01: Gasoline Quality

Transient Plane Source Method: This is a transient method that involves applying a short heat pulse to a flat disc in contact with the material and measuring the temperature rise on the disc.

Laser Flash Method: This transient method involves applying a short heat pulse to one side of a material and measuring the time it takes for the heat to travel through the material and reach the other side. This method suits various materials, including solids, liquids, and gases.

Thermal conductivity testing is important in many applications, such as determining the insulation properties of building materials, assessing the performance of heat exchangers, and optimizing the design of electronic devices. It is also used in materials science research to understand the properties of various materials better and to develop new materials with improved thermal conductivity.