Dose effects in He implanted Eurofer97 steel

13th International Workshop on Slow Positron Beam Techniques and Applications

Carvalho, I.^1,2,3 ; Schut, H.^2 ; Fedorov, A.^3 ; Luzginova, N.^3 ; Desgardin, P.^4 ; Sietsma, J.^5

Materials Innovation Institute (M2i), Mekelweg 2, 2628 CD, Delft, Netherlands^1

Delft University of Technology, Faculty of Applied Sciences, Mekelweg 15, 2629 JB, Delft, Netherlands^2

Nuclear Research and Consultancy Group (NRG), Westerduinweg 3, 1755 LE, Petten, Netherlands^3

CEMHTI-CNRS, 3A rue de la Férolerie, 45071 Orléans Cedex, France^4

Delft University of Technology, Faculty of Mechanical, Maritime and Materials Engineering, Mekelweg 2, 2628 CD, Delft, Netherlands^5

关键词: Eurofer-97 steel;    Helium release;    Implantation-induced defects;    Irradiation conditions;    Reduced activation ferritic/martensitic steel;    Temperature increase;    Vacancy cluster;    Vacancy-type defects;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/505/1/012019/pdf
DOI  :  10.1088/1742-6596/505/1/012019

来源: IOP

【 摘 要 】

Reduced Activation Ferritic/Martensitic steels are being extensively studied because of their foreseen application in fusion reactors. To reproduce neutron irradiation conditions, Eurofer97 samples were implanted at room temperature with helium ions at energies of 500 keV and 2 MeV and doses of 1×1015-1017He /cm2. The implantation induced defects were characterized by positron beam Doppler Broadening (DB). The samples were annealed in the range 300-1500 K, in 100 K steps. As the temperature increases, the annealing of vacancies and vacancy clusters is noticed and followed by the coalescence of HenVm clusters. At temperatures around 1200 K HeV pairs dissociate and bubbles are formed. Above 1300 K the helium release from bubbles is observed. The S-W graphs reveals that the samples have similar positron traps up to 1200 K. At 1200 K helium bubbles are noticed and the S, W pair shows a clearly distinct behaviour from the S, W values of vacancy type defects. As the temperature increases and helium is release, the S, W pairs shift towards the S, W's of vacancies.