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Self-passivating, so-called smart alloys are under development for a future fusion power plant. These alloys containing tungsten, chromium and yttrium must possess an acceptable plasma performance during a regular plasma operation of a power plant and demonstrate the suppression of non-desirable oxidation of tungsten in case of an accident. The up-scaling of the bulk smart alloys to the reactor-relevant sizes has begun and the first samples with a diameter of 50 mm and thickness of 5 mm became available. The samples feature high relative density of above 99% and good homogeneity. With production of bulk samples, the research program on joining the smart alloy to the structural material was initiated. In a present study, the novel titanium–zirconium–beryllium braze was applied successfully to join the smart alloy to the Rusfer-reduced-activation steel. The braze has survived at least a hundred of cyclic thermal excursions in the range of 300–600 °C without mechanical destruction.

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An investigation of the effect of hydrogen peroxide (H 2 O 2 ) on corrosion crack growth can be considered as a necessary stage in a study of the SCC of pipeline steels in the presence of dissolved oxygen and other oxidants. It was found that the presence of hydrogen peroxide at a low concentration (5 mM) results in a deceleration of the crack growth. With an increase in the concentration of H 2 O 2 , the crack growth rate increases. The change in the steel corrosion rate at various H 2 O 2 concentrations agrees with the dependence of the crack growth rate on the oxidant concentration. The conclusion has been made that the crack growth in a weakly acidic electrolyte (pH 5.5) is determined by the metal dissolution process. Hydrogen charging of the metal indirectly affects the crack growth by increasing the surface coverage with hydrogen, which decreases the steel dissolution rate.