Abstract
Controlled nuclear fusion is a new way to produce ideal energy utilising hydrogen isotopes as fuel, where deuterium and tritium undergo a nuclear reaction at extremely high temperatures to form helium and a neutron. A growing interest in hydrogen permeation barriers is driven by approaches aimed at reducing hydrogen embrittlement on structural materials as well as radiological isotope leakage induced hazards during the service of fusion reactor. Cr2O3 is one of the potential surface coatings to improve the hydrogen resistance of stainless steel substrates, but so far the irradiation effect of high energy particles as well as the helium created by radioactive decay on the hydrogen permeation properties are far from clear. Herein, nanoscale Cr2O3 passive film formed on electroplated chromium coating and then oxidized by oxygen-poor plasma was used to investigate the influence of irradiated helium on the hydrogen permeation behaviors. Passive films have been irradiated with 300 keV helium ions at the fluence of 1×1016 ions·cm-2 prior to exposure of hydrogen at 350oC. The interactions between the embedded helium and hydrogen were analyzed by comprehensive surface analyses. The depth of ion implantation has been simulated by SRIM, microstructural evolution of these irradiated passive films has been estimated by using the non-destructive conductive atomic force microscopy, the chemical states and defect characteristics of sample were measured by X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy. Measurements indicate that He induced defects are formed in the passive film and lead to enhanced diffusion of hydrogen of the sample surface.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have