Temperature profiles, the size of the heat-affected zone and dilution in electroslag welding

Abstract

A mathematical model was developed to represent the three-dimensional temperature field in the slag, the metal pool and the baseplate regions in the electroslag welding process. The spatially distributed heat generation patterns used in the calculations were obtained from the solution of the electric field equations. The output from the model were the temperature fields in the baseplate, the dilution, the size of the heat-affected zone and the grain growth in the heat-affected zone. Reasonably good agreement was obtained between the predictions based on the model and experimental measurements reported in the literature and those obtained in the Welding Laboratory, Massachusetts Institute of Technology. The two important findings that result from this work are that for electroslag welding systems the heat-affected zone is relatively uniform and its size is not markedly affected by the process parameters; furthermore, the percentage dilution is appreciably influenced by process parameters, such as the plate gap and the liquidus temperature.