Positron Lifetime Measurement of Plastically Deformed Iron Single Crystals

Abstract

Positron lifetime measurement and analysis were made for pure iron single crystals plastically deformed at room temperature and 77 K. Both second component I 2 (175 psec, dislocations and jogs) and third component I 3 (about 350 psec, vacancy clusters) in the specimen deformed at 77 K were larger than those in the specimen deformed at room temperature. It must be concluded that jogs in the low temperature deformed specimen play an important role in positron trapping and also in production of vacancies. However, the jog number density estimated from the experiment is too high, which suggests that some modification in the model of positron trapping by jogs may be required.