Hot Disk Thermal Conductivity Analysers
TPS2500 |
TPS1500 |
TPS500 |
 |
 |
 |
Thermal conductivity 0.005 to 500 W/mK Temperature -100C to 750C |
Thermal conductivity 0.01 to 400 W/mK Temperature -100C to 750C |
Thermal conductivity 0.03 to 100 W/mK Temperature -100C to 200C |
What sort of samples can be measured?
The Hot Disk method is used for determining thermal properties of materials such as
| Metals | Alloys, forged materials |
| Ceramics | Composites |
| Minerals | Plastics |
| Powders | Building materials (including highly insulating materials), |
| Biomaterials (in vivo and in vitro) | Multilayered materials |
How is the measurement made?
The disk sensor is placed between two pieces of the sample material and is then heated by a constant electrical current for a short period of time. The generated heat dissipates from the sensor into the surrounding unknown sample material, causing a rise in temperature of the sensor and surrounding sample material. The average transient temperature increase of the sensor, of the order 0.5 - 5 K, is simultaneously measured by monitoring the change in electrical resistance. The Temperature Coefficient of Resistivity of the sensor material correlates the change in resistivity with the corresponding change in temperature.
The time duration of the heating current is normally limited by the size of the sample, in order to avoid influence from outside (lateral) boundaries of the sample. In addition, if the sample is much larger than the sensor diameter, the probing depth of the heating (thermal penetration depth) should be of the same magnitude as the radius of the Hot Disk sensor, ensuring stable values of both thermal conductivity and diffusivity.
Above is an example of a Hot Disk Sensor (actual size 85mmx35mm)