The lattice thermal conductivity of some palladium and platinum alloys

The thermal conductivity of a number of palladium-silver, platinum-gold and platinum-iridium alloys has been measured in the temperature range 2°K to 120°K. Below about 30°K the lattice thermal conductivity is an order of magnitude smaller than in noble metal alloys of similar concentrations. The low values are explained in terms of the strong electron-phonon scattering which is present in these metals, although it is concluded that it is impossible to decide at present whether the important electronic transitions are s to d or d to d. At higher temperatures, measurements from transition metal alloys are largely independent of solute concentration, and tend to the values observed in noble metal alloys. It is inferred that at ∼100°K, the lattice resistance arises mainly from phonon-phonon U-processes.