THERMAL CONDUCTIVITY OF NICKEL AND ITS ALLOYS

The thermal conductivity of pure nickel and a number of dilute Ni-Co, Ni-Fe, Ni-Cu and Ni-Pd alloys has been measured in the temperature range 2-100°K. An attempted separation of the measured conductivity into its electronic and lattice components indicates rather large deviations from the thermal equivalent of Matthiessen's rule. These deviations are greatest in Ni-Co and smallest in Ni-Pd, suggesting a close correlation with the deviations from Mattheissen's rule itself observed previously in the same alloys and attributed to a spin-mixing mechanism. Below 15°K these deviations are negligible so that the lattice conductivity can be evaluated. The values obtained are close to those found in noble metal alloys, and are not unusually low as observed in alloys of palladium and platinum.