Transport Properties of Concentrated Ag-Pd and Cu-Ni Alloys from 300–1000 K

Abstract

For temperatures above 300 K, thermal conductivity data for concentrated binary silver-palladium and copper-nickel alloys are scarce. A recent review and analysis of thermal conductivity data for selected binary alloy systems by Ho et al.1 included extrapolations of existing data for Ag-Pd and Cu-Ni into composition and temperature regions where data were absent. Over a broad composition range, the electronic Lorenz functions that were calculated showed high temperature values significantly below the Sommerfeld value, Lo = 2.443 × 10−8 V2K−2. These results strongly suggested the collection of additional experimental data to confirm the published extrapolation. Values for thermal conductivity, λ, electrical resistivity, ρ, and absolute Seebeck coefficient, S, were measured for the alloys silver (50 wt %)-palladium (50 wt %) and copper (50 wt %)-nickel (50 wt %) in the temperature interval 300–1000 K. Results for the three transport properties presented in this paper show that the electronic Lorenz functions exceed the Sommerfeld value over most of the temperature range studied.