Determination of thermal diffusivity and thermal conductivity of Fe-Al alloys in the concentration range 22 to 50 at.% Al

The thermal diffusivity of Fe-Al alloys in the concentration range 22 to 50 at.% Al was measured within a temperature range of 20 to 600 °C. The thermal diffusivity of the Fe-25 and 28 at.% Al alloys decreases with increasing temperature up to the Curie temperature, and then it increases up to the temperature when the D0₃ ↔ B2 transformation occurs. The thermal diffusivity of Fe-22 at.% Al alloys increases with rising temperature up to the temperature when D0₃ ↔ B2 transformation occurs, and then it decreases. A further decrease in thermal diffusivity follows up to the Curie temperature. The thermal diffusivity of Fe-34 and Fe-40 at.% Al increases monotonically with the rising temperature. The thermal diffusivity of Fe-50 at.% Al alloys decreases only up to 100 °C, and does not change any further with increasing temperature. Thermal conductivity is the highest for Fe-25 and Fe-50 at.% Al alloys at room temperature. Thermal conductivity rises for all studied alloys with increasing temperature. The smallest increase was registered for Fe-25 at.% Al alloys.