- Turkish Journal of Physics
- Vol: 24 Issue: 4
- Positron Annihilation and XRD Studies on Deformed Al-Alloys with low concentration of Mg
Positron Annihilation and XRD Studies on Deformed Al-Alloys with low concentration of Mg
Authors : Emad Badawi, M. A. Abdel-rahman, S. A. Mahmoud
Pages : 543-550
View : 11 | Download : 4
Publication Date : 9999-12-31
Article Type : Makaleler
Abstract :Positron behaviour at grain boundaries is characterized by their bulk diffusibility D, their bulk free lifetime tf and their trapped lifetime tt (tt > tf). Al-Mgx samples (x = 0-1.4 at %) have been homogenized at 573 K for 12 hours. The mean lifetime, as (indirectly) measured at various concentrations, show a good fitting with Sigmodel giving tt = 180.664 ps and tf = 163.9 ps. The mean lifetime was found to vary exponentially with the degree of deformation. The XRD study showed that preferred orientation occurred at degrees of deformation > 32 %, whereas the peak intensity then increases with sample deformation. Heat treatment (recrystallization) is also followed by XRD study. The peak intensities decrease with increasing annealing time (attributed to recrystallization), but it does not completely reverse to the condition origin. For all cases, no peaks of Mg were revealed indicating the positron annihilation as a sensitive technique for detecting low concentrations in alloys.Keywords : Turk. J. Phys., 24, (2000), 543-550. Full text: pdf Other articles published in the same issue: Turk. J. Phys., vol.24, iss.4.