Thermal Conductivity Analyzers and Heat-Transfer Measurement

A thermal conductivity analyzer measures thermal conductivity and can provide quantitative data for material development and process evaluation. Steady-state and transient methods are used.

In the laser flash method, a short laser pulse strikes one surface of a specimen and an infrared detector records the temperature-rise curve at the rear face. The method directly determines thermal diffusivity; thermal conductivity is calculated when density and specific heat capacity are supplied. Examples include high-temperature superconducting ceramics, carbon-fiber composites, and aerogels, including insulation-layer design for spacecraft propellant tanks.

Measurements range from milliwatt-level heat flow to kilowatt-level heat transfer and from biological tissue to metal alloys. PCB anisotropy can be analyzed for electronics heat-sink layout, while layer-by-layer testing of wall insulation can quantify thermal-resistance contributions in prefabricated buildings.

Interchangeable specimen fixtures accommodate bulk materials, thin films, and powders. An environmental chamber can simulate operating conditions and allow study of humidity and pressure effects. A battery company used variable-temperature testing to study the relationship between electrolyte wetting and electrode thermal conductivity.

Automated fitting can process raw data and compensate for radiative losses. A three-dimensional thermal-imaging accessory can display isotherm distributions on a specimen surface and visualize heat-flow paths. Further fields of use include microelectronic packaging and geothermal-resource exploration.