Suppression of helium bubble growth in palladium by prior cold working

Materials Science Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102, India; Department of Physics, Cochin University of Science and Technology, Cochin 682 022, India
Journal of Nuclear Materials (Impact Factor: 2.02). 01/1996; DOI: 10.1016/0022-3115(96)00359-5

ABSTRACT Growth of helium bubbles in palladium, having different pre-irradiation sample treatments and subsequently implanted with 50 appm of helium, has been investigated by positron lifetime spectroscopy. Presence of dislocations has been found to enhance the density of nucleated bubbles. A suppression of helium bubble growth due to the presence of dislocations is established. Bubble growth is reduced by over-pressure in dislocation-containing samples.

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