Numerical modeling of inconel 738LC deposition welding: Prediction of residual stress induced cracking

A predictive tool has been implemented to determine the suitable conditions for deposition welding of inconel 738LC which is particularly susceptible to hot cracking. Cracking criteria related to liquation phenomenon and reheating rely on comparisons between residual stresses derived from numerical modeling and cracking resistance identified from the confrontation between numerical and experimental results of deposition welding performed on fir tree turbine blades test specimens. A contribution to the validation of the proposed simultaneous thermal, metallurgical and mechanical numerical modeling was based on their application to the repair of upstream guide vanes. In addition, the study has shown the importance of the heating temperature prior to welding.