Industrial Applications of Positron Annihilation
J. Phys. IV France 05 (1995) C1-163-C1-169
Positron Dopplerbroadening Measurements in Cu-Al-Ni Based Shape Memory AlloysD. Segers1, I. Hurtado2, L. Dorikens-Vanpraet1 and J. van Humbeeck2
1 RUG, Vakgroep subatomaire en stralingsfysica, Proeftuinstraat 86, B-900 Gent, Belgium
2 KUL, Departement metaalkunde en toegepaste materiaalkunde, de Croylaan 2, B-3030 Heverlee, Belgium
Positron annihilation Dopplerbroadening measurements were carried out on Cu-Al-Ni based alloys to which Ti, and Ti and Mn was added. The measurements reveal a drastic effect in the S-parameter behavior when the defects anneal out at the transition from martensite to the beta phase. When crossing the transition region several times, an increase of the S-parameter value is observed. This is interpreted as due to the formation of dislocations and precipitate-martensite interfaces. In the alloy with Mn a distinct behavior is observed attributed to vacancy cluster formation.
© EDP Sciences 1995