Join us at the International Thermal Conductivity Conference (ITCC) and the International Thermal Expansion Symposium (ITES).

##### Transient Plane Source (TPS)
 Materials Solids, Liquids, Paste and Powder Thermal Properties Thermal Conductivity, Thermal Diffusivity, Specific Heat Capacity, & Thermal Effusivity Temperature Range -160°C to 1000°C Accuracy, Repeatability 5%, 2% Standard ISO 22007-2

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##### Modified Transient Plane Source (MTPS)
 Materials Solids & Small Particle Powder Thermal Properties Thermal Effusivity Temperature Range Room Temperature Accuracy, Repeatability 5%, 2% Standard ASTM 7984 – Fabrics

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## Frequently Asked Questions

##### What is thermal effusivity?
Thermal effusivity is a measure of how quickly a material can exchange heat with its surroundings. It combines the thermal conductivity and the square root of the product of the density and specific heat capacity of the material. It quantifies the material’s ability to conduct heat and respond to changes in temperature.
##### What are the units of thermal effusivity?
The units of thermal effusivity depend on the system of units used. In the International System of Units (SI), thermal effusivity is typically expressed in square root of watts per meter squared Kelvin (W/m²·K^0.5). Other common units include square root of calories per centimeter squared second Kelvin (cal/cm²·s·K^0.5) in the CGS system.
##### What is thermal effusivity testing? How is thermal effusivity measured?
Thermal effusivity testing is a measure of its ability to exchange thermal energy with its surroundings. Although the quantity of thermal effusivity can be expressed in bulk property terms of e = √k∙ρ∙Cρ when measured, it is not measured in terms of bulk properties.

Thermal effusivity can be measured using various techniques, including the transient methods such as the laser flash method. These methods involve measuring the response of a material to a sudden thermal perturbation and extracting its thermal effusivity from the obtained data.

##### How does thermal effusivity differ from thermal conductivity?
While thermal conductivity measures the material’s ability to conduct heat, thermal effusivity goes beyond that by considering both the conductive and the transient aspects of heat transfer. It accounts for the material’s ability to both store and transfer heat, making it a more comprehensive parameter in characterizing thermal properties.
##### Why is thermal effusivity important?
Thermal effusivity is important in various applications where the rapid exchange of heat between a material and its surroundings is critical. It influences the thermal response of materials, such as in determining the efficiency of insulation, evaluating the performance of thermal interface materials, and optimizing heat transfer in electronic devices.
##### Can thermal effusivity be used to compare different materials?
Yes, thermal effusivity provides a means to compare the heat exchange properties of different materials. By measuring the thermal effusivity, engineers and researchers can assess and compare how effectively different materials can transfer heat or respond to changes in temperature, aiding in material selection and design optimization.