Session: MF-22-01 3D Crack Growth Simulation Using FEA

Paper Number: 106254

106254 - Pwscc Crack Initiation and Growth of Alloy 182 Weld Using Curved Tensile Specimen With a Notch 

As a part of development of FE-based natural crack growth simulation system, primary water stress corrosion crack (PWSCC) initiation and growth tests were performed. To simulate the cracks in the pipes, curved tensile specimens with a machined notch were fabricated from block of Alloy 182 welds. The PWSCC tests were performed in the simulated pressurized water reactor (PWR) primary coolant environment. The specimens were subjected to slow strain rate tensile testing for in an autoclave connected to recirculation loop simulating PWR environment. During the test, crack initiation and growth were monitored by direct current potential drop method (DCPD). After the tests, the measured and monitored crack sizes were compared and corrected. To measure crack size, the specimens were sectioned in several location to reveal the crack initiation and growth path. The measured crack size and morphology were compared with the results of the FE-based natural crack growth simulation. In addition, the crack initiation and growth mechanisms were investigated by analyzing the oxide layer formed on the crack surface by transmission electron microscope (TEM) with energy dispersive spectroscope (EDS). For the detailed characterization of oxide layer along the path of the crack, various electrochemical analyses were also performed for the selected regions on the crack surface.

Presenting Author: Changheui Jang KAIST

Presenting Author Biography: Prof. Jang is a professor at the Department of Nuclear and Quantum Engineering in the Korea Advanced Institute of Science and Technology (KAIST), Korea. He has been working on the variety issues related to the cracking and embrittlement of metallic materials in pressurized water reactors. Currently he is actively involved in environmentally-assited fatigue (EAF), primary water stress corrosion cracking (PWSCC), and thermal aging embrittlement of CASS and austenitic SS welds.

Authors:

Changheui Jang KAIST
Hyeon Bae Lee Korea Advanced Institute of Science and Technology
Okonkwo Bright Ogwugwa Korea Advanced Institute of Science and Technology