کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1499956 | 993327 | 2011 | 4 صفحه PDF | دانلود رایگان |
Spatially resolved positron annihilation was employed for mapping lateral defect distribution in Cu deformed by high-pressure torsion. Parameters describing Doppler broadening of the annihilation peak were used for mapping the spatial distribution of defects. In comparison with microhardness showing a clear development towards homogeneity, positron annihilation revealed that spatial distribution of defects was far from uniform, even after 25 turns. This was mainly due to a higher concentration of deformation-induced vacancies at the periphery compared with the center.
► Doppler broadening (DB) of annihilation radiation was used as a novel technique for two dimensional mapping of lateral defect distribution in ultra fine grained Cu produced by high pressure torsion.
► This paper introduces DB mapping and compares it with standard microhardness (HV) characterization.
► DB mapping enables to visualize lateral distribution of dislocations and in particular deformation-induced vacancies which are invisible in HV mapping.
► Hence, DB mapping can be considered as a complementary technique to standard HV characterization.
Journal: Scripta Materialia - Volume 65, Issue 2, July 2011, Pages 171–174