Study on Positron Annihilation Life for New U₃Si₂-Al Fuel Plates

Microstructure damage configuration and transformation of shell materials for U₃Si₂-Al fuel plates under different technical conditions were studied by positron annihilation technique. The study showed that micro-effects in the shell material for tempered fuel plates were mostly single vacancy point defects, that in cooled fuel plates were mostly couple vacancies and dislocation, and that in eroded fuel plates were mostly layer-dislocation and small vacancy groups. There were no large vacancy groups which had effect on the safety of fuel plates in all samples. Some technique such as temper and eroding would change microstructure damage of shell materials, and also alter mechanical capability of fuel plates.