How does the thermal conductivity of a material change with temperature?
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The thermal conductivity of a material generally increases with temperature. In region I, at low temperatures, the thermal conductivity is determined by the physical dimensions of the material and increases quickly with temperature . In region II, the thermal conductivity reaches a maximum value, usually around the Debye temperature . In region III, the thermal conductivity decreases due to the lack of phonon harmony and the effect of phonon dispersion . Finally, in region IV, at very high temperatures, the thermal conductivity becomes independent of temperature . However, it is worth noting that there are some conflicting experimental results, where the thermal conductivity decreases with increasing temperature . Overall, the relationship between thermal conductivity and temperature is complex and depends on various factors such as material properties and phonon behavior.
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| The paper states that at high temperatures, the thermal conductivity of the ceramic materials cerium dioxide (CeO2) and magnesium oxide (MgO) is computed using first principles and compared to measurements. It is mentioned that high temperature softens phonon frequency and reduces four-phonon scattering strength in both ceramics. However, the specific change in thermal conductivity with temperature is not explicitly mentioned in the paper. | |
| The thermal conductivity of a material changes with temperature in four regions: it increases quickly in region I, reaches a maximum value in region II, diminishes in region III, and becomes independent of temperature in region IV. | |
42 Citations | The paper states that the thermal conductivity of insulation materials increases when the temperature increases. However, it does not provide specific details on how the thermal conductivity changes with temperature for different materials. |
| The paper states that the thermal conductivity of solid materials changes significantly when the temperature range is from 20k to 80k, but the change is minimal from 80k to 300k. | |
| The thermal conductivity of two-dimensional IV A materials increases with the increase of temperature, according to the research mentioned in the paper. |
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