The annealing of deformed potassium: I. an experimental study

Measurements of residual resistance have been used to study the recovery of high-purity potassium wires deformed at 4·2 K and below. Details of the full recovery spectrum are given in this paper. The recovery is completed by a wide stage (at about 150 K) which arises from the final annealing of dislocations, but the main feature of recovery is a large stage (accounting for about 40% of the recovery) centred at 15 K. Point defects anneal in this stage by a process which involves several mechanisms, discussed in the following paper. The parameter of chief interest in the recovery process is the migration energy of the monovacancy, E 1v M. The value for this, which proves to be almost independent of the model, is 0·034±0·006 eV, as compared with 0·071 eV, a value recently calculated by Torrens and Gerl. Evidence is given of an anomalous difference between the properties of vacancies in potassium and in sodium.