Simulated irradiation of 16Cr – 4Al – 2W – 0.3Ti – 0.3Y2O3 ODS steel, perspective for thermonuclear reactors in the plasma focus facility “Vikhr”

Abstract

A study of the radiation-thermal resistance of ferritic steel 16Cr – 4Al – 2W – 0.3Ti – 0.3Y2O3 was made. This ODS (oxide dispersion strengthened) steel is perspective for fusion applications. The “Vikhr” Plasma Focus installation was used to introduse of powerful pulsed flows of helium ions and helium plasma. The power density of a beam of fast helium ions and high-temperature helium plasma flows was ~ 108 and 107 W/cm2 at exposure times of ~ 50 and 100 ns, respectively. The number of pulses N varied in the range from 10 to 30. The rate of evaporation and radiaсtive sputtering changed slightly with an increase in the number of pulses of energy flows acting on the material and amounted to h ≈ 0.01 – 0.02 μm/puls. The irradiated surface after repeated melting under the action of a pulsed radiation-thermal load with powerful energy flows acquired a wave-like character with inclusions of dispersed micro particles of the second phase, containing mainly yttrium, oxygen, aluminum, iron, and titanium. At the same time, in contrast to the refractory metals (W, Mo, Ti) earlier under similar radiation conditions studied, no micro- and macro cracks were formed on the surface of the material facing the plasma. “Vikhr” Plasma Focus setup proved to be an effective tool for simulation testing of candidate materials with magnetic and inertial plasma confinement.