Morais L.D.C.Magnabosco R.2019-08-202019-08-202017MORAIS, LUARA DA COSTA; Magnabosco, Rodrigo. Experimental investigations and DICTRA ® simulation of sigma phase formation in a duplex stainless steel. CALPHAD-COMPUTER COUPLING OF PHASE DIAGRAMS AND THERMOCHEMISTRY, v. 58, p. 214-218, 2017.0364-5916https://repositorio.fei.edu.br/handle/FEI/2291© 2017 Elsevier LtdSigma phase formation in an UNS S31803 duplex stainless steel aged at 940 °C was evaluated by computational simulation in DICTRA® software, using MOB2 diffusion database and TCFE8 thermodynamic database. Simulation results were compared to experimental tests. Two models were tested in DICTRA® software: in model 1 sigma phase are placed between ferrite and austenite, and in model 2 sigma is placed at one side of ferrite region, and austenite on the other. The volume fraction of sigma and ferrite phases obtained in model 1 showed adherence to the experimental results up to 7200 s (2 h) of simulation, indicating the ability of the model in the description of early stages of sigma formation. Model 2 showed good agreement with experimental data up to 86,400 s (24 h) of simulation. The composition profile obtained by the simulation of the model 1 represented better the impoverishment in Cr and Mo in ferrite/sigma and austenite/sigma interfaces, while the profiles obtained by the simulation of model 2 described better the partition of the chemical elements between austenite and ferrite during sigma formation.Acesso RestritoArtigo10.1016/j.calphad.2017.07.006Computational simulationDICTRA®Duplex stainless steelSigma phase