Effect of Secondary Phase Precipitation on the Corrosion Behavior of Duplex Stainless Steels

Materials

Kai Wang Chan¹ 

[1] Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; E-Mail

关键词: duplex stainless steel;    sigma phase;    spinodal decomposition;    nitride;    intergranular corrosion;    critical pitting temperature;    stress corrosion;    welding;   

DOI  :  10.3390/ma7075268

来源: mdpi

【 摘 要 】

Duplex stainless steels (DSSs) with austenitic and ferritic phases have been increasingly used for many industrial applications due to their good mechanical properties and corrosion resistance in acidic, caustic and marine environments. However, DSSs are susceptible to intergranular, pitting and stress corrosion in corrosive environments due to the formation of secondary phases. Such phases are induced in DSSs during the fabrication, improper heat treatment, welding process and prolonged exposure to high temperatures during their service lives. These include the precipitation of sigma and chi phases at 700–900 °C and spinodal decomposition of ferritic grains into Cr-rich and Cr-poor phases at 350–550 °C, respectively. This article gives the state-of the-art review on the microstructural evolution of secondary phase formation and their effects on the corrosion behavior of DSSs.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.