Short-Range Order and the Nucleation of Long-Range Order in Ni-Rich Nickel-Niobium Alloys

Abstract

The changes in the electrical resistivity of nickel-rich Ni-Nb alloys due to the formation of short-range order exhibit an anomalous dependence on the solute concentration. This anomaly can be explained by the formation of embryos of long-range order of the type Ni₈Nb in alloys approaching the NisNb composition and near the critical temperature for long-range order. In the absence of a critical concentration of quenched-in vacancies, short-range-order formation only has been detected during ageing below the critical temperature.