Positron Dopplerbroadening Measurements in Cu-Al-Ni Based Shape Memory Alloys
نویسندگان
چکیده
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.
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