Hydrogen Absorption in Weldments of Overlaid Claded Pressure Vessel

Cracks was found in type 347 stainless steel internal attachment welds of a reactor for a high temperature, and highpressure hydrogen service. One of the possible causes of cracking is low cycle fatigue cracking induced by repetition ofthermal stress to embrittled weld metal. Type 347 weld metal loses its ductility by presence of sigma phase andhydrogen

Approximation of Hydrogen Induced Delayed Fracture of Overlaid Cladding in Pressure Vessels Steel Structure

Distribution and electronic states of interstitial hydrogen atoms in the iron lattice are discussed in regard to their influence to the lattice bonding, and theory of hydrogen induced delayed fracture of steel based upon it is proposed. Characteristics of delayed fracture are accordingly well accounted for