Abstract:
Duplex stainless steels are commonly used in petrochemical industries due to their good mechanical properties and high corrosion resistance in environments containing halides. However, it may present a deleterious phase called sigma, caused by chromium diffusion which weakens locally the passive layer generating localized corrosion. The sigma phase is formed by the decomposition of ferrite at temperatures between 800 °C and 1000 °C, depending on the diffusion-process time. A way to evaluate the influence of the sigma phase is through a polarization curve which measures the current density at different voltages, showing the range that the material is active or passive. This article aims at determining changes of anodic polarization curves of this steel as a function of time of aging at 850 °C.
Reference:
PEREIRA, Henrique Boschetti; VIEIRA, Fabiana Yamasaki Martins; SANTOS, Celia Aparecida Lino dos; PANOSSIAN, Zehbour. Efeito do tempo de envelhecimento na resistência à corrosão de aço inoxidável duplex UNS S32205. Revista IPT, Tecnologia e Inovação, v.1, n.3, p. 31-40, dez., 2016.
Access to the article on the Journal’s website:
http://revista.ipt.br/index.php/revistaIPT/article/view/30/20
Duplex stainless steels are commonly used in petrochemical industries due to their good mechanical properties and high corrosion resistance in environments containing halides. However, it may present a deleterious phase called sigma, caused by chromium diffusion which weakens locally the passive layer generating localized corrosion. The sigma phase is formed by the decomposition of ferrite at temperatures between 800 °C and 1000 °C, depending on the diffusion-process time. A way to evaluate the influence of the sigma phase is through a polarization curve which measures the current density at different voltages, showing the range that the material is active or passive. This article aims at determining changes of anodic polarization curves of this steel as a function of time of aging at 850 °C.
Reference:
PEREIRA, Henrique Boschetti; VIEIRA, Fabiana Yamasaki Martins; SANTOS, Celia Aparecida Lino dos; PANOSSIAN, Zehbour. Efeito do tempo de envelhecimento na resistência à corrosão de aço inoxidável duplex UNS S32205. Revista IPT, Tecnologia e Inovação, v.1, n.3, p. 31-40, dez., 2016.
Access to the article on the Journal’s website:
http://revista.ipt.br/index.php/revistaIPT/article/view/30/20