BS EN ISO 8044:2020 pdf free.Corrosion of metals and alloys一Vocabulary.
BS EN ISO 8044 threshold stress intensity factor for stress corrosion cracking Krscc  stress intensity factor above which stress corrosion crack propagation is sustained Note 1 to entry: The threshold stress intensity factor is a concept of linear elastic fracture mechanics (LEFM) and is applicable when the plastic zone size is large compared with the microstructure, the crack is sufficiently long, and a high constraint to plastic deformation prevails, i.e. under plane strain predominant conditions. For growing stress corrosion cracks, LEFM is not necessarily applicable in all detail but is adopted as a pragmatic tool that is commonly used.Note 2 to entry: Stress corrosion cracks may initiate at a surface or a surface defect and grow in the “small crack”regime at stress intensity factor levels below the apparent threshold stress intensity factor. Therefore, LEFM is not applicable in the“small crack” regime.stress-oriented hydrogen-induced cracking SOHIC staggered small cracks formed approximately perpendicular to the principal stress (residual or applied) resulting in a “ladder-ike” crack array linking (sometimes small) pre-existing HIC (4.39) cracks Note 1 to entry: The mode of cracking can be categorised as sulfide stress corrosion cracking (SSCC) (4.43) caused by a combination of external stress and the local strain around hydrogen-induced cracks. SOHIC is related to SSCC
and HIC/stepwise cracking (SWC) (4.42). It has been observed in parent material of longitudinally welded pipe and in the heat-affected zone (HAZ) of welds in pressure vessels. SOHIC is a relatively uncommon phenomenon usually associated with low-strength ferritic pipe and pressure vessel steels. Note 2 to entry: Compare with hydrogen embrittlement (4.32].[SOURCE: ISO 15156-1:2015, 3.22, modified一In Note 1 to entry, “SSC” has been replaced with“SSCC”. Note 2 to entry has been added.]exfoliation corrosion stratified form of subsurface stress corrosion (4.30) of susceptible primary wrought alloy mill products having a highly directional grain structure, accompanied by detachment of separate layers from the body of the material, formation of cracks and finally usually complete layer-by-layer disintegration of metal Note 1 to entry: Exfoliation generally proceeds along grain boundaries, but with certain alloys and tempering it may develop along transgranular paths or a mixed intergranular/transgranular path. Note 2 to entry: Layer corrosion can be developed on the first stage. BS EN ISO 8044 pdf downlaod.