Low temperature coefficient of resistivity Ag–Cd and Ag–Sn alloys—structure and transport

The microstructure vis-a-vis electrical transport behavior of Ag–Cd and Ag–Sn binary alloys in the temperature range 70–300 K has been studied. The 22.2 wt.% Cd and 29.4 wt.% Cd alloys were both found to have a single-phase structure made of solid solution of Ag. The lattice parameter however increased with increasing Cd content in the alloy. The microstructure of 17.7 wt.% Sn and 23.5 wt.% Sn alloys however is made of two phases Ag4Sn and Ag3Sn. The resistivity of Ag–Cd alloys increased with increasing Cd content and the temperature coefficient of resistivity (TCR) decreased to 1560 ppm K−1 for the 29.4 wt.% Cd alloy compared to 4100 ppm K−1 for pure Ag. The lowest TCR however was obtained for the 17.7 wt.% Sn alloy, 375 ppm K−1, which has a room temperature resistivity of 23.93 μΩ cm.