Abstract:
The features of diffusion in two-phase (duplex) stainless steel (DSS), interaction the effect of hydrogen with trap sites in various steel structures, the influence of plastic deformation, local stresses and hydrogen concentrations on localized corrosion and hydrogen embrittlement. Available data indicate that the diffusivity of DSS is insensitive to plastic deformation and increase in dislocation density, but it is influenced by grain boundaries and interfaces $\alpha/\gamma$-phases The influence of hydrogen on stability is considered $\gamma$-phases, formation of second phases and hydrogen trap semi-coherent grain boundaries. The mechanisms that ensure crack propagation are discussed: brittle, associated with decohesion in the region of maximum hydrostatic stress, and plastic in the austenite phase – due to shear decohesion along the slip plane. Reviewed the influence of the yield stress of duplex steel on the susceptibility to hydrogen embrittlement, as well as on correlation of the steel embrittlement index with the total amount of absorbed hydrogen.