Abstract
The width of extended dislocations in Cu-8·01 at.% Si alloy has been measured as a function of temperature using in situ heating experiments in a HVEM. A drastic increase in the width of the stacking-fault ribbon of extended dislocations ha been observed at around 560 K, both on heating and cooling the specimens. The increase in the width of the stacking-fault ribbon has also been observed on a specimen which was annealed in bulk form followed by a very slow cooling (10 K per day). These results are explained best by postulating the Suzuki effect. Effects of electron irradiation on the solute segregation are mentioned briefly.