This presentation was made at the 2019 NAFEMS World Congress in Quebec Canada

Resource Abstract

Finite element analysis (FEA) of residual stress in a single pass bead-on-plate weld is carried out in this paper. The modelling case was selected from the research work on residual stress measurement and analysis round robin of a single weld bead-on-plate specimen (AISI 316L stainless steel plate, dimension 180mmx120mmx17mm, and with a 60mm weld bead in the center and of the longitudinal orientation), that was organized by the Task Group 1 (TG1) of the European Network on Neutron Techniques Standardisation for Structural Integrity (NET). The modelling investigation was conducted using the commercial software package ABAQUS, and a sequentially coupled thermal-mechanical analysis approach was adopted. In the thermal analysis, a double ellipsoid heat source model was employed and implemented through the ABAQUS user subroutine DFLUX, the parameters of which were subsequently calibrated using a cross-sectional macrograph of the weld bead. In the mechanical analysis, three material hardening models were used, namely isotropic hardening, kinematic hardening and combined isotropic-kinematic hardening. Overall by comparison with the experiment, it has been shown that the thermal modelling method used in this study is capable of predicting the temperature history experienced by the weldment during welding. With regards to the prediction of weld residual stresses, it has been demonstrated that the combined isotropic-kinematic hardening model gives the most reasonable results compared with the experimental measurements, whereas the isotropic hardening model tends to overestimate the weld residual stress and the kinematic hardening model tends to underestimate the weld residual stress.