2013, Volume 8, Issue 3
Frontiers of Mechanical Engineering >> 2013, Volume 8, Issue 3 doi: 10.1007/s11465-013-0250-1
Local fracture properties and dissimilar weld integrity in nuclear power plants
Key Laboratory of Pressure Systems and Safety (Ministry of Education), East China University of Science and Technology, Shanghai 200237, China
Next Previous
Abstract
In this paper, the local fracture properties in a Alloy52M dissimilar metal welded joint (DMWJ) between A508 ferritic steel and 316 L stainless steel in nuclear power plants were investigated by using the single-edge notched bend (SENB) specimens, and their use in integrity assessment of DMWJ structures was analyzed. The results show that the local fracture resistance in the DMWJ is determined by local fracture mechanism, and which is mainly related to the microstructures and local strength mismatches of materials at the crack locations. The initial cracks always grow towards the materials with lower strength, and the crack path deviation is mainly controlled by the local strength mismatch. If the local fracture properties could not be used for cracks in the heat affected zones (HAZs), interface and near interface zones, the use of the fracture properties ( -resistance curves) of base metals or weld metals following present codes will unavoidably produce non-conservative (unsafe) or excessive conservative assessment results. In most cases, the assessment results will be potentially unsafe. Therefore, it is recommended to obtain and use local mechanical and fracture properties in the integrity assessment of DMWJs.
京公网安备 11010502051620号
