Numerical Simulation and Experimental Investigation of Residual Stresses in the Circumferential Butt GTAW of Incoloy 800H Pipes

Abstract

The residual stresses developed during the circumferential butt gas tungsten arc welding (GTAW) process of Incoloy 800H pipes were simulated using the finite element method. A decoupled thermostructural model was developed in three dimensions. The element birth and death technique was used for the addition of filler material in the weld pool. The Goldak double ellipsoidal model was used to simulate the distribution of arc heat during welding. The plastic behavior of the material was described by Von Mises yield function and the bilinear kinematics hardening was assumed. To validate the thermostructural model, both temperature and residual stress distributions within the pipes were measured using thermocouples and strain gages, respectively. Good agreements were found between the experimental and simulation results. The model was then used to predict distribution of residual stresses during the GTAW of Incoloy 800H pipes and to study effects of process parameters on the residual stresses.

Experimental investigation and numerical simulation on continuous wave laser ablation of multilayer carbon fiber composite

“…Nowadays, there have been extensive researches on modeling of laser material processing. 16–19 Cheng et al. 20 developed a three-dimensional finite element model to simulate the transient temperature field and the hole dimension in the laser drilling of carbon fiber composites, and good agreement with his experiment was observed.…”

Numerical simulation and experimental investigation of temperature and residual stresses in GTAW with a heat sink process of Monel 400 plates

“…The arc efficiency in the GTAW process was assumed as 0.6 (Kermanpur et al, 2008;Purmohamad et al, 2010). The welding parameters are shown in Table 2.…”

“…For example, a 3D simulation model has been developed for predicting residual stresses in circumferential welds of steel pipes including pipe diameter effects (Lee and Chang, 2008). The effect of heat input as a most important process parameter on residual stresses in the GTAW process of pipes was recently studied (Purmohamad et al, 2010).…”

The Role of Goldack Double Ellipsoidal Parameters in Temperature Distribution for the GTAW Process

“…Along with experimental work, numerical studies also carried out to check the performance and accuracy of the numerical tools [7]. Purmohamad et al used numerical simulation tools for predicting the bead pro le, stress etc., caused by the welding process [8]. But getting accurate predictions the geometrical parameters for Goldack model must be given properly in the numerical simulation Once again it was proved that numerical studies can give perfect predictions on the effect of the welding process.…”