On the base of physical-and-mechanical modelling for cleavage microcrack behaviour a new local criterion for cleavage fracture is formulated. Cleavage fracture of pressure vessel steel under various loading history is investigated. It has been experimentally shown that for steels after static prestrain by tension and cyclic prestrain brittle fracture critical stress is described by increasing f...

The effects of baking on the mechanical properties and fracture characteristics of low-carbon boron (10B21) steel screws were investigated. Fracture torque tests and hydrogen content analysis were performed on baked screws to evaluate hydrogen embrittlement (HE) susceptibility. The diffusible hydrogen content within 10B21 steel dominated the fracture behavior of the screws. The fracture torque ...

The effect of prior air exposure on rupture life of superalloys is reported. Oxygen is identified as a damaging species leading to severe losses in both rupture life and ductility. Similar embrittlement is observed in pure nickel and a mechanism is proposed in terms of reduced grain boundary mobility. Two cobalt base alloys and an oxide dispersion strengthened nickel base alloy do not embrittle...

Theories, experimental results and applications associated with hydrogen behavior in amorphous metals and alloys are reviewed. An emphasis is made on the potential use of these advanced materials for hydrogen storage technology. Therefore, several properties that are especially relevant for such applications are assessed. These include structural models for hydrogen occupancy, sorption characte...

Grain boundary (GB) segregation of impurity/solute atoms in surveillance test specimens of a commercial western-type pressurized water reactor pressure vessel (RPV) steel has been observed by using state-of-the-art 3D atom probe (3DAP) field ion microscope (laser-assisted local electrode-type atom probe: laser-LEAP). The GB segregation is considered to be an origin of the embrittlement of the R...