| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Use of Large Scale Facilities to Understand the Physical Metallurgy of Fe-based Alloys
|
| Presentation Title |
Nucleation and Evolution of Sigma Phase and Nitrides during Heat Treatment and Welding of Duplex Stainless Steels |
| Author(s) |
Shirin Nouhi, Niklas Pettersson, Lars Höglund, Amer Malik, Jan Y. Jonsson, Staffan Hertzman, Sten Wessman, Andreas Stark, David Lindell |
| On-Site Speaker (Planned) |
Shirin Nouhi |
| Abstract Scope |
Duplex stainless steels have unique properties in terms of strength, ductility, fatigue, and corrosion resistance. During heat treatment or welding, the molten phase solidifies into ferritic phase and austenite precipitates while cooling. The holding time and cooling cycles, however, require a delicate choice of time and rate to avoid the formation of intermetallic phases, such as sigma phase, and allow nitrogen diffusion which promotes austenite formation. For optimizing production processes and developing the application of duplex steels, understanding the conditions where the intermetallic phases precipitate is a key challenge. In this project, we have used Wide-Angle X-ray Scattering (WAXS) and Small-Angle X-ray Scattering (SAXS) in order to explore the phase tranformation, probe the nucleation and follow the kinetics of sigma phase and nitrides formation, and quantify the precipitates during heating and cooling processes relevant to e.g. welding. The results are compared to the simulations using DICTRA software. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |