Recovery of Electrical Resistivity in Gold Quenched from Below 700°C

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Abstract
The residual electrical resistivity as measured at liquid helium temperature was determined as a function of annealing time at 62.4°C, for high-purity gold quenched from temperatures between 700°C and 400°C at the rate of 25 000°C/sec. For quenches begun from below 500°C an initial increase in resistivity occurs, followed by the usual decrease with aging time. The time to reach maximum resistivity is found to be a function of the quenched-in resistivity. The increase in resistivity may be due to vacancy clustering during the aging process. Further study is required to determine the role of impurity atoms in this process. For quenches above 500°C, some clusters apparently form during the quenching process and grow, acting as stable vacancy sinks during subsequent aging; hence no increase occurs for these quenches. A calculation of the formation of divacancies and trivacancies during the annealing process, neglecting interactions with impurities, shows appreciable clustering upon annealing following a low-temperature quench for binding energies of 0.3 ev. A maximum in the calculated resistivity due to formation of clusters is reached at the same order of magnitude of time as the maximum in resistivity is observed, and is followed by an approximately exponential decay which also corresponds to the experimental observations.