Figure 7
From: Probing intergranular mixed transgranular stress corrosion cracking under the high constant load
The mechanism model of an IG- mixed TGSCC process. a A SCC crack on two cleavage facets consisting of a crystal plane and a grain boundary. b Synergistic effects of the CEP assisted cleavage on σI ≥ σIC and the ductile shear on τ ≥ τC in the elastic–plastic cohesive zone, in which some dislocations are pinned by the obstacles or pile up ahead of the SCC crack tip. c A slip plane (1 1 1) gliding by a Burgers vector, b, in a canister-like elastic strain field induced by an edge dislocation. Wherein, the CEPs are composed of the hydrogen atoms and the electronegative ions such as the chloride ions for the chloride-solution SCC of the austenitic stainless steel, while the obstacles contains the grain boundaries, the CEPs, the precipitates, the Cottrell or Snoek atmospheres and the L-C dislocation locks.
