The effect of cold-work on the electrical resistivity of alloys and the law of recovery

Summary The change in resistivity due to cold-work has been determined for a number of binary alloy series having copper, silver or gold as basic metal. The effects observed are very different in the different alloy systems. A change as large as 42% of the total resistivity is found in one case. Alloys from the systems gold-chromium and gold-iron show a decrease of resistivity when cold-worked. In addition to the binary series, some alloys containing three or four components have also been investigated, and on the basis of the results obtained the question of the influence of the different solutes upon the change of resistivity is discussed. Results are given regarding the recovery of the resistivity changes as a function of time for different annealing temperatures. The resistivity change Δϱ as a function of temperatureT and time τ is found to obey the law Δϱ=cτ ⁿ exp (−nE/RT), wheren is a number of the order 0.1–0.4 andE is the activation energy of the process;R is the gas constant, andc a quantity of proportionality. Alloys belonging to the following binary systems have been investigated: Cu-Al, Cu-Si, Ag-Al, Ag-Mn, Ag-Sn, Au-Al, Au-Cr, Au-Mn, Au-Fe and Au-Sn, and the following multi-component systems: Au-Mn-Cr, Au-Mn-Cr-Fe and Au-Al-Cr.