Abstract
In the present work pure iron and low activation steel F82H have been neutron irradiated at temperatures in the interval 50°C - 350°C to a dose of 0.23 dpa (displacements per atom). The formation of defects has been investigated by the use of positron annihilation spectroscopy (PAS). In addition iron has been irradiated to different doses in the range 0.01 - 0.4 dpa at 50°C and 100°C and the dose dependence of the electrical conductivity determined. The results demonstrated that the formation of voids takes place during neutron irradiation of pure iron in the whole temperature range. For irradiation temperatures of 50°C and 100°C also a high density of micro-voids was observed. Voids and micro-voids were also detected in low activation F82H steel for a low irradiation temperature (50°C), while for irradiation close to the temperature of annealing stage V (250°C), no voids or micro-voids could be detected. Surprisingly, irradiation at the higher temperature of 350°C again resulted in void formation. The annealing behaviour of iron irradiated at 50°C and at 100°C did not show any significant difference. Coarsening of the micro-void and void population takes place below stage V by migration and coalescence of the micro-voids and voids.
The dose dependence of the electrical conductivity of iron showed a lower conductivity for the specimens irradiated at 50°C than at 100°C. This has been
associated with the segregation of carbon at about 70°C where carbon becomes
mobile.
The dose dependence of the electrical conductivity of iron showed a lower conductivity for the specimens irradiated at 50°C than at 100°C. This has been
associated with the segregation of carbon at about 70°C where carbon becomes
mobile.
Original language | English |
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Place of Publication | Roskilde |
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Publisher | Risø National Laboratory |
Number of pages | 23 |
ISBN (Print) | 87-550-2824-1 |
Publication status | Published - 2002 |
Series | Denmark. Forskningscenter Risoe. Risoe-R |
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Number | 1241(EN) |
ISSN | 0106-2840 |
Keywords
- Risø-R-1241
- Risø-R-1241(EN)