Study on Micro-Structure and Tensile Mechanical Properties of Dissimilar Metal Weld Joint Connecting Steam Generator Nozzle and Safe-End

The safe-end of a steam generator (SG) nozzle dissimilar metal weld (DMW) for pressurized water reactors (PWRs) is the weakest point failure which crucial safe operation nuclear power station. Related to materials micro-structures, uniaxial stress–strain relationship basic input parameter plant design, safety evaluation, and life management. In this paper, micro-structure tensile mechanical properties DMW European reactor (EPR) were studied. Vickers hardness tester, optical microscope, electron back scatter diffraction used analyze joint. addition, residual strain joint base material, heat-affected zone, metal, fusion boundary region Based on digital image correlation (DIC) technology, obtained. results show that an accurate welded joints can be obtained by using DIC technique, relatively weak link, concentrated in zone. This study provides valuable engineering information regarding in-service performance testing, structural analysis evaluation welds containing defects.