Artigo Acesso aberto Revisado por pares

Influence of the microstructure on the degree of sensitization of a duplex stainless steel UNS S31803 aged at 650ºC

2013; Associação Brasileira de Metalurgia e Materiais (ABM); Associação Brasileira de Cerâmica (ABC); Associação Brasileira de Polímer; Volume: 16; Issue: 6 Linguagem: Inglês

10.1590/s1516-14392013005000125

ISSN

1980-5373

Autores

Evelin Barbosa de Mélo, Rodrigo Magnabosco, Carlos de Moura Neto,

Tópico(s)

High Temperature Alloys and Creep

Resumo

This work evaluates the phase transformations during aging of an UNS S31803 DSS at 650ºC and its influence on the DOS. The material was solution treated at 1175ºC and then aged at 650ºC for times up to 360 h. SEM-BSC images indicate the formation of Cr2N, σ and χ phases in the samples aged at 650ºC. The analysis of DL-EPR curves, obtained in a 1 M H2SO4 + 0.25 M NaCl + 0.01 M KSCN solution, shows an increase in DOS values for samples aged at 650ºC. Probably, this increase observed in DOS values is mainly related to the presence of Cr- and/or Mo-depleted α, as a result of σ phase, χ phase and/or Cr2N formation at 650ºC. Moreover, a possible healing up of Cr- and/ or Mo-depleted areas is observed between 1 h and 4 h of aging at 650ºC.

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