Thermal conductivity of W-Cu composites at various temperatures

The effect of temperature on the electrical resistivity and thermal conductivity of W-Cu composites had been studied. In case of pure W and Cu, the thermal conductivity decreased with increase in temperature. However, the W-Cu composites showed increased thermal conductivity with increase of temperature up to 500°C, and then the conductivity decreased with increasing temperatures. This increase in thermal conductivity is explained by the increased number and movement of electrons as well as increased conduction paths for the electrons. The scattering of phonons is believed to be responsible for the decrease of thermal conductivity at the temperature of above 500°C.