Stress Corrosion Cracking Behavior in the Transition Region of Alloy 182/Low-Alloy Reactor Pressure Vessel Steel Dissimilar Metal Weld Joints in Light Water Reactor Environments

The influence of ppb levels of chloride impurities on the stress corrosion crack growth behaviour of low-alloy steels under simulated boiling water reactor conditions

“…The maximal KI at the final load step was ≤ 15 MPa•m 1/2 . The crack plane in the DMW specimens was perpendicular to the fusion boundary and the pre-crack tip located in the Alloy 182 weld metal [4]. The DMW tests thus started with an actively growing intergranular SCC crack in the Alloy 182 weld metal [4].…”

“…The investigated materials are characteristic for RPVs of Western light water reactors. The specimens were fabricated either directly from the forged ingots and hot-rolled steel plates [9] or from simulated Alloy 182-RPV steel dissimilar metal joints [4] of the corresponding steels ( Table 3). The corresponding chemical compositions are given in Tables 4 and 5.…”

“…Under the simultaneous effect of the reactor coolant, thermo-mechanical operational loads and irradiation, cracks can initiate and grow in the RPV during service by environmentally-assisted cracking (EAC) and thermo-mechanical fatigue. Important examples from the field are, e.g., the RPV feedwater nozzle corner cracking by thermo-mechanical fatigue and EAC in boiling water reactors (BWR) [1,2] or the stress corrosion cracking (SCC) in RPV penetration and attachment welds in BWRs and pressurized water reactors (PWR) [3,4]. Fabrication-or welding-induced incipient cracks (e.g., hot and relaxation cracks in the cladding or cladding/RPV interface) were observed in few isolated cases.…”

“…The SCC [7], strain-induced corrosion cracking (SICC) [8] and corrosion fatigue (CF) [9] crack growth behaviour of different low-alloy RPV steels and weldments/heat-affected zones (HAZ) and the SCC crack growth behaviour in the Alloy 182-RPV steel transition region of dissimilar metal welds (DMW) [3,4] under BWR normal water (NWC) and hydrogen water chemistry (HWC) conditions as well as the role of dynamic strain ageing (DSA) in EAC of low-alloy steels (LAS) [7,10] was therefore investigated at Paul Scherrer Institut (PSI) in detail in the last two decades. Currently, these investigations are extended to potential high-temperature water and hydrogen effects on the fracture toughness and tearing resistance of RPV steels [5,6].…”

Corrosion Behavior of Keyhole-Free Friction Stir Spot Welded Joints of Dissimilar 6082 Aluminum Alloy and DP600 Galvanized Steel in 3.5% NaCl Solution

“…Compared with the traditional welding method, this technology produces a high joint quality, small welding distortion, small residual stress, green welding process and no pollution, and is widely used in aerospace, shipping, transportation and other fields [1][2][3][4][5].…”