Effect of temperature and rhenium content in precipitates on dispersion hardening of tungsten

Yulia R. Sharapova, Research Laboratory for Metals and Alloys under Extreme Impacts, Ufa University of Science and Technology, Ufa, Russia;
Arseny M. Kazakov, Research Laboratory for Metals and Alloys under Extreme Impacts, Ufa University of Science and Technology, Ufa, Russia;Follow
Elena A. Korznikova, Research Laboratory for Metals and Alloys under Extreme Impacts, Ufa University of Science and Technology, Ufa, Russia
Alexandr Zinovev, Institute for Nuclear Materials Science, SCK CEN, Mol, Belgium;
Dmitry Terentyev, Institute for Nuclear Materials Science, SCK CEN, Mol, Belgium;
Sergey V. Dmitriev, Institute of Molecule and Crystal Physics, UFRC of Russian Academy of Sciences, Ufa, Russia

Abstract

Tungsten (W) is being developed as a plasma-facing material for fusion reactors, where it is subjected to MeV neutron irradiation, low-energy helium isotope particles, and high temperatures. These conditions lead to the formation of point defects, dislocation loops, voids, and transmutation into rhenium (Re) and osmium (Os), which form precipitates that significantly impact dislocation motion and increase hardness. This study uses molecular dynamics modeling to examine the interaction between an edge dislocation and Re-rich particles of various stoichiometries, specifically coherent bcc-phase particles and noncoherent σ-phase precipitates. Results show that shear stress increases by approximately 20-40% with larger particle size (3-5 nm diameter) and higher Re content (50-75 at.%), while temperature (600–1400 K) has a weak effect on critical shear stress. Coherent bcc-phase particles are weak barriers to dislocations, whereas noncoherent σ-phase precipitates are strong obstacles. The study reveals that dislocations typically cut through these particles, except for noncoherent spherical ones, which are bypassed via the Orowan mechanism.

Recommended Citation

Sharapova, Yulia R.; Kazakov, Arseny M.; Korznikova, Elena A.; Zinovev, Alexandr; Terentyev, Dmitry; and Dmitriev, Sergey V. (2024) "Effect of temperature and rhenium content in precipitates on dispersion hardening of tungsten," Karbala International Journal of Modern Science: Vol. 11 : Iss. 1 , Article 3.
Available at: https://doi.org/10.33640/2405-609X.3386