Low-Radiation Vanadium-Based Alloys
Development of Scientific Fundamentals for Development of Low-Activation Radiation - and Corrosion-Resistant Vanadium-Based Alloys to be Used as Structural Materials for the first Wall and Tritium Blanket Thermonuclear Fusion Installations and Reactors
Tech Area / Field
- FIR-MAT/Materials and Materials Conversion/Fission Reactors
3 Approved without Funding
All-Russian Scientific Research Institute of Non-Organic Materials named after A. Bochvar, Russia, Moscow
- FEI (IPPE), Russia, Kaluga reg., Obninsk\nVNIITF, Russia, Chelyabinsk reg., Snezhinsk\nUral Branch of RAS / Institute of Metal Physics, Russia, Sverdlovsk reg., Ekaterinburg
- Hokkaido University / Faculty of Engineering, Japan, Sapporo\nUniversity of Tokyo / Department of Quantum Engineering and Systems Science, Japan, Tokyo\nPacific Northwest National Laboratory / Dept. of Energy, USA, WA, Richland\nPacific Northwest National Laboratory, USA, WA, Richland
Project summaryThe purpose of this project is to develop a database required for working out of scientific recommendations to optimize the compositions of low activation vanadium alloys designed for use in environment-safe prospective thermonuclear fusion plants, as well as to set the range of these alloys application in view of criteria defined by such exposure factors as temperature, thermal and radiation fluxes, static and cyclic loads, and external media (liquid lithium, hydrogen plasma).
Recent research carried out within the framework of the Fusion Reactor-Tokamak conceptual projects has shown that the potential environmental advantages of fusion reactors as compared to fission reactors can only be realized through the use of the so-called low activation materials (LAM) as structural materials. Most promising for use as low activation structural materials (SM) for the demo and subsequent power Fusion Reactor-Tokamak, also for new type reactors (utilizing accelerators, lasers) are the vanadium-based alloys of the V-Ti-Cr system.
Some uncertainty in defining the exact composition of alloys of the above system (V-Ti-Cr) is still present today, since the available database on separate alloys is still insufficient (with the data being often contradictory), and, what’s important, there have not been worked out the accurate criteria of vanadium alloys serviceability assessment, which does not allow to give a true explanation of the causes of radiation effects in vanadium alloys, influencing adversely the SM serviceability under the operating conditions.
It is the purpose of this project to create a scientific base for setting the criteria to control serviceability of vanadium alloys under the working conditions of fusion reactor power-intensive units. This may be achieved both with due account of the physical-chemical factors of the alloys metallurgical production process (ensuring uniform distribution of the alloy basic components; reaching an optimal content of alloying elements and impurities, such as oxygen, nitrogen, carbon, hydrogen; heat-treatment and machining modes optimization, etc.),and through investigation of the effects of exposure to different types of irradiation: various-spectra neutron, ion, and electron. The named goal will be reached through study of the structure and the physical and mechanical properties of materials to find out the characteristics of alloy samples in the initial state. It is planned that the alloys of small-scale melts, after their detailed certification as to composition and treatment variations, tritium-bearing and tritium-less, will be irradiated in the BR-10 and IVV-2 reactors and accelerators under different temperatures and fluences.
In the final run, the results obtained should bring us to a closer understanding of the processes going in materials under their operating conditions, which will allow us to look into the ways to increase the vanadium alloys resistance to radiation and corrosion damage at exposure to hydrogen and its isotopes, and to find the optimal alloy composition.