抄録
The precipitation of Ag from a super-saturated Pb–0.038 at% (0.02 mass%)Ag solution was followed by measuring the resistivity change on aging between 195 K and 513 K after quenching from 558 K . During the isochronal aging (45 s), the resistivity decreases in two different temperature-ranges: A, below 283 K; and B, 283–423 K . The resistivity decays in two stages (IA and IIA) with the isothermal aging in the range A . In the stage IA the reaction is of quadratic with an activation energy 37.7±3.0 kJ/mol. During the isothermal aging in the range B, the decay occurs in a single stage (IB), the reaction of which is of first-order with an activation energy 50.2±2.0 kJ/mol.
These results suggest that the Ag transport during precipitation is controlled by the movement of silver interstitials in the range A and by that of interstitial-vacancy pairs in the range B.
