Ion Implantation Induced Defects in Fe-Cr Alloys Studied by Conventional Positron Annihilation Lifetime Spectroscopy

The influence of chromium on the radiation damage resistance of the iron based alloys has been studied using conventional positron annihilation lifetime spectroscopy (PALS). Experimental data evaluation has been supported by the former theoretical calculation of positron lifetimes in the studied materials and well-defined types of defects. For this purpose, density functional theory (DFT) computation method has been applied. The spectrum of used 22Na positron source was decomposed into discrete fractions to better calculate efficiency of near surface layers study. For the experimental simulation of alpha-radiation and obtaining of defined cascade collisions in the materials, helium implantation was used. Different level of the implanted dose (6.24e17 ¿ 3.12e18 cm-2) corresponds to local damage up to 90 DPA acquired in thin <1 um region. Experimental measurement has been performed using the PALS technique on the four different Fe-Cr binary alloys (2.36; 4.62; 8.39; 11.62 wt% of Cr). The results showed that chromium has a significant effect on the size and density of the implanted defects and specific Cr content should prevent the vacancy clusters formation.

KRSJAK Vladimir;  SOJAK Stanislav;  SLUGEN Vladimir;  PETRISKA Martin; 

2011-03-09

IOP PUBLISHING LTD

JRC63181

0953-8984,   

http://iopscience.iop.org/1742-6596/265/1/012014/pdf/1742-6596_265_1_012014.pdf,    https://publications.jrc.ec.europa.eu/repository/handle/JRC63181,   

10.1088/1742-6596/265/1/012014,