Low-Temperature Transport Properties of Commercial Metals and Alloys. III. Gold-Cobalt

Abstract
The thermal conductivity, electrical resistivity, and Lorenz number are given in the temperature range 4–100°K for the widely used thermocouple wire, gold‐2.1 atomic percent cobalt alloy. The total thermal conductivity is relatively low: from 0.01 watt/cm°K at 4°K to 0.23 at 100°K. The lattice contribution to the total thermal conductivity is larger than the electronic contribution. The electrical resistivity is nearly independent of temperature, but does have a definite minimum of about 1.20×10−5 ohm‐cm at 30°K. Because of the relatively large contribution of the lattice term to the total thermal conductivity, the Lorenz number is considerably above the electronic Sommerfeld value, 2.44×10−8 watt‐ohm/°K2.