Ricardo Luiz Perez Teixeira, Allexia Izabella Pinheiro Damasceno, Rafael Nascimento, Sebastião Bruno Vilas Boas, José Carlos de Lacerda, Renata Neves Penha, Rogério Fernandes Brito, Haroldo Lhou Hasegawa, Tarcísio Gonçalves de Brito, Eduardo Miguel da Silva
This work explores the phase changes in welded AISI 316 L stainless steel coated with a nickel-watts bath containing niobium microparticles. The CALPHAD method, using Thermo-Calc with TCFE7, TCFE12, and PRISMA, simulated phase changes during rapid cooling. Simulations identified amounts of austenite, delta ferrite, and a small amount of sigma phase during cooling from 1450 °C to 25 °C. The influence of the Ni-Nb coating on stability and element diffusion was assessed. Results were confirmed by microscopy, microhardness testing, ferritoscopy, and electrochemical testing. The CALPHAD model reliably predicted phase stability, supporting its use in alloy design and in the optimization of welded stainless steel. This study’s approach lays the groundwork for the detailed background and motivation discussed in the following introduction.