Effect of thermal aging on the microstructure and mechanical properties of stainless steel UNS S31803.
No Thumbnail Available
Date
2020
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Duplex stainless steel UNS S31803 exhibits high mechanical strength with high corrosion properties, due to
its microstructure composed of ferrite and austenite phases, in equal proportion. When the UNS S31803 steel
is submitted to high temperatures, some precipitations can occur, such as nitrites, carbides, and third phases
(e.g. sigma phase -σ, and alpha prime - α'). These phases are deleterious in relation to the mechanical
properties and corrosion resistance, and their effects are analyzed regarding the properties of the steel. In
order to evaluate the precipitation of this deleterious phase, isothermal treatment was done at 500°C for 144
hours (α' phase) and at 850ºC for 80 minutes (σ phase). The results were obtained through the microstructural
analysis and tensile tests. The presence of sigma phase was verified in the grain boundary, an increase in the
mechanical resistance with a loss of toughness. There was as well as an increase in mechanical resistance
with the precipitation of α', with less loss of ductility than that observed in the experiments involving the
presence of sigma phase.
Description
Keywords
Duplex stainless steel, Embrittlement, Sigma phase, Mechanical properties
Citation
COSTA, J. M. G. et al. Effect of thermal aging on the microstructure and mechanical properties of stainless steel UNS S31803. Matéria, v. 27, n. 1, artigo e13128, 2022. Disponível em: <https://www.scielo.br/j/rmat/a/qVgRht4NYXM4wqpd9rkHWDn/abstract/?lang=en>. Acesso em: 15 mar. 2023.