POLYMERS

Fiber-Reinforced Epoxy —Thermal Conductivity & Thermal Diffusivity

More and more polymers, metals or ceramics are being reinforced with fibers to improve their bending strength and to adjust them to special applications.

In many cases, the fiber reinforcement results in a high degree of anisotropy to the mechanical and thermal transport properties. By employing special sample holders, the flash technique allows analysis of this anisotropy in the Thermal DiffusivityThermal diffusivity (a with the unit mm2/s) is a material-specific property for characterizing unsteady heat conduction. This value describes how quickly a material reacts to a change in temperature.thermal diffusivity and Thermal ConductivityThermal conductivity (λ with the unit W/(m•K)) describes the transport of energy – in the form of heat – through a body of mass as the result of a temperature gradient (see fig. 1). According to the second law of thermodynamics, heat always flows in the direction of the lower temperature.thermal conductivity. The measurement example clearly demonstrates that the values for both the Thermal DiffusivityThermal diffusivity (a with the unit mm2/s) is a material-specific property for characterizing unsteady heat conduction. This value describes how quickly a material reacts to a change in temperature.thermal diffusivity and Thermal ConductivityThermal conductivity (λ with the unit W/(m•K)) describes the transport of energy – in the form of heat – through a body of mass as the result of a temperature gradient (see fig. 1). According to the second law of thermodynamics, heat always flows in the direction of the lower temperature.thermal conductivity, perpendicular to the fiber direction are significantly lower than the results of the in-plane test (in the fiber direction). (measurement with LFA 447 NanoFlash®)