The competing effects of temperature and neutron irradiation on the microstructure and mechanical properties of ITER grade tungsten

Philippos Papadakis, Dellis Spilios, Konstantina Mergia, Vasileois Chatzikos, Dmitry Terentyev, Giovanni Bonny, Andrii Dubinko, Wouter Van Renterghem, Milan Konstantinovic, Spyros Messoloras, Gerald Pintsuk

Research outputpeer-review

1 Downloads (Pure)


In the current work, ITER grade W irradiated at 1200 oC to a dose of 0.18 dpa has been investigated by Transmission Electron Microscopy (TEM), Positron Annihilation Spectroscopy (PAS), X-ray diffraction, impulse excitation and depth-sensing micro-indentation. The results are compared with those of annealed unirradiated W at 1200 oC. In the as fabricated material dislocations and small vacancy clusters of 1 to 3 vacancies are present. After annealing at 1200 oC, the small vacancy clusters disappear and only the dislocations with almost un-changed density remain. Also, hardness is reduced by 4% and creep increases by 13%. Neutron irradiation at 1200 ◦C results in the increase of the dislocation line density by 3.7 times and in the formation of dislocation loops and voids. The irradiation also causes a hardness increase of about 20% and a creep decrease of 15%. Both the elastic and shear moduli decrease by 4% after irradiation at 1200 ◦C contrary to the effect of only annealing at this temperature which causes an increase in their values by 4%. Texture changes are observed only after neutron irradiation.
Original languageEnglish
Article number112608
Pages (from-to)1-11
Number of pages11
JournalFusion Engineering & Design
StatePublished - 1 Jul 2021

Cite this