Journal of Phase Equilibria and Diffusion

, Volume 38, Issue 3, pp 332–342 | Cite as

Multicomponent Phase Diagram of Lean Duplex Stainless Steel UNS S82441 and Its Application to Evaluate the Microstructure in the Heat Affected Zone

  • Evandro Armini de Pauli
  • Claudio Geraldo Schön
  • Sérgio Duarte BrandiEmail author


Duplex stainless steels are Fe-Cr-Ni-Mo-N alloys with nitrogen replacing some nickel to improve its properties. These steels have a balanced microstructure, which means that ferrite (α) and austenite (γ) are in equal proportions of approximately 50% by volume. These alloys have a tendency to form intermetallic precipitates such as chromium nitrides and sigma phase (σ), depending on their chemical composition and welding thermal history. Precipitation of these intermetallic phases can impair mechanical and corrosion properties. In addition, material processes such as welding and heat treatment can change the balanced microstructure. The objective of this work was to compare phases formed during heat treatment and welding of duplex stainless steel UNS S82441 with the equilibrium phases predicted by Thermo-calc® software. In general, the results showed good agreement between predicted and measured phases, as well as, agreement between the measured volume fraction of austenite in the heat-affected zone and austenite predicted by Thermo-calc® software.


intermetallic phases lean duplex stainless steel Thermo-calc® UNS S82441 welding 



The authors appreciate the donation of Outokumpu duplex UNS S82441 steel, and Voith in providing consumables and to Prof. Dr. Flávio Beneducci for help with phase diagrams discussion.


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Copyright information

© ASM International 2017

Authors and Affiliations

  • Evandro Armini de Pauli
    • 1
  • Claudio Geraldo Schön
    • 1
  • Sérgio Duarte Brandi
    • 1
    Email author
  1. 1.Department of Metallurgical and Materials EngineeringEscola Politecnica da USPSão PauloBrazil

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