Session: MF-22-01 Materials and Fabrication: General Topics II

Paper Number: 61897

Start Time: Wednesday, July 14, 2021, 05:00 PM

61897 - Assessment of Residual Stress for Thick Butt-Welded Plate of a Reactor Pressure Vessel Steel 

Residual stress is one of the important influence factors in the structural integrity assessment of the nuclear components. However, at the present, there are few examples of residual stress measurements for thick butt-welded plates such case of the reactor pressure vessels (RPVs). In this study, the residual stresses generated by butt-welding of thick plates of RPV steel, which have almost the same thickness of 140 mm as actual boiling water reactor pressure vessel, were measured for post-welded heat-treated condition using the deep-hole-drilling technique. In addition, thermo–elastic–plastic creep analyses by or without considering the phase transformation in the heat-affected zone using the finite element method (FEM) were performed to evaluate the residual stress produced by butt-welding and post-weld heat treatment. In case of the analysis considering phase transformation, the fractions of the phases, such as martensite, bainite and ferrite, are calculated based on the kinetics of phase transformation using the commercial FEM analysis code Abaqus. By comparing the analytical results with the experimentally determined values, we found good agreements for the residual stress distributions within the weld and the base material near the welded part. In the presentation, the effect of phase transformation on residual stress distribution of butt-weldment of thick plate will be discussed.

Presenting Author: Yoosung Ha Japan Atomic Energy Agency

Authors:

Yoosung Ha Japan Atomic Energy Agency
Shigetaka Okano Osaka University
Hisashi Takamizawa Japan Atomic Energy Agency
Jinya Katsuyama Japan Atomic Energy Agency
Masahito Mochizuki Osaka University