Daniella Caluscio dos SantosRodrigo Magnabosco2023-08-262023-08-262010-07-26SANTOS, D. C. DOS; MAGNABOSCO, R. Influenzce of the sigma phase formation in pitting potential of UNS s31803 duplex stainless steel in 0,6M NACL AGED at 850 E 900°C. 65th ABM International Congress, 18th IFHTSE Congress and 1st TMS/ABM International Materials Congress 2010, p. 3594-3605, v. 4, jul, 2010.https://repositorio.fei.edu.br/handle/FEI/4987The main purpose of this work is to analyze the mechanisms and kinetics of sigma phase formation of UNS S31803 stainless steel after isothermal aging between 850 e 900°C, evaluating the influence of sigma phase formation on pitting potential in 0.6M NaCl solution. Solution treated samples of the UNS S31803 duplex stainless steel were isotermically aged at 850°C or 900°C up to 360 h. The microstructural characterization of the samples was made through quantitative metallography, ferritscope analysis and Vickers microhardness. The cyclic polarization tests used to the determination of the pitting potential were conducted in polished samples. The electrochemical behavior of aged UNS S31803 duplex stainless steel in 0.6M NaCl solution is strongly dependent on the microstructure, since both changes in mechanisms and kinetics of sigma phase formation influenced the pitting potential of the material. Increasing aging time lead to the decrease of pitting potential, due to the formation of chromium impoverished regions. Oscillations in pitting potential values were noted due to the chromium redistribution enabled by easy diffusion of this element in high temperatures.Acesso RestritoArtigo de eventoDuplex stainless steelPitting corrosionSigma phase