Welding of Different Metals Across Ferritic Substrates: A Thermal Modeling: Thermodynamic Simulations of Dissimilar Metal Welds in Ferritic Substrates under High-Temperature Conditions

Abstract

In the modern era, scientists are able to accurately predict the microstructural evolution ofcomplex metallurgical systems, including the formation of phases at elevated temperatures over l.ongperiods of time. Those calculations are useful because they provide insight without the need forlaborious and costly experiments. Computational simulations are especially useful in the powergeneration industry, where the service parameters have a significant impact on the materials used.Dissimilar metal welds (DMWs) ranging in hardness from T23 to T91 will be the focus of thisinvestigation into the application of thermodynamic simulations to their behaviour under hightemperature,creep-like conditions. Precipitation sequences in the base metals, as well as carbonmigration in DMWs from the higher alloyed to the lower alloyed material at elevated temperatures, andthe distribution of precipitates across the fusion line of the DMWs, are all calculated using the softwareMatCalc. The simulation results are validated by testing creep-exposed cross-weld samples at 80 MPa,600 °C, and 625 °C for up to 14,000 hours.