Predicting effect of temperature field on sensitization of alloy 690 weldments

Abstract

The present study develops two 3-D finite element (FE) thermal models of the temperature field induced within an Alloy 690 butt weld fabricated using the two-pass GTA welding and the laser beam welding (LBW) methods, respectively. The welding thermal cycles of the two welding methods are simulated using ANSYS software based upon a moving heat source model and the high-temperature thermal physical property data are derived in the JMatPro database. The validity of the numerical model is confirmed by comparing the simulation results with the corresponding experimental findings. Agreement is found between the numerical results for the temperature field and the experimental temperature measurements. In addition, the FEM models we use can help us estimate the range and size of the sensitization zone and the time duration of the sensitization temperature. Overall, the results provide useful insight into the sensitization tendencies of Alloy 690 weldments. © 2011 The Japan Institute of Metals.