Numerical and experimental investigation into effect of temperature field on sensitization of AISI 304 in butt welds fabricated by gas tungsten arc welding

This study examines the effect of the temperature field on the sensitization tendencies of AISI 304 two-pass butt welds fabricated using the gas tungsten arc welding (GTAW) method. The thermal cycles induced in the two-pass welding process are simulated using ANSYS software based upon a moving heat source model and the function of Element Birth and Death was employed also in the filled metal GTA welding. The validity of the numerical model is confirmed by comparing the simulation results with the corresponding experimental results. The results show that the heat-affected zone (HAZ) in the 2nd pass specimen is susceptible to intergranular corrosion (IGC). However, the HAZ in the 1st pass specimen shows no obvious signs of IGC. The difference in the sensitization tendencies of the two specimens is attributed to a difference in their respective heating and cooling times.