Precipitation behavior of the sigma phase with Ni and Mn content variations in superaustenitic stainless steel weld metal
Autor: | Changmin Lee, Changhee Lee, Youngchai Lee, Seunggab Hong |
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Rok vydání: | 2018 |
Předmět: |
Materials science
Precipitation (chemistry) Mechanical Engineering Gas tungsten arc welding Metallurgy Sigma 02 engineering and technology Welding 021001 nanoscience & nanotechnology Condensed Matter Physics Microstructure 020501 mining & metallurgy law.invention 0205 materials engineering Depletion region Mechanics of Materials law Phase (matter) General Materials Science 0210 nano-technology Weld metal |
Zdroj: | Materials Characterization. 144:148-154 |
ISSN: | 1044-5803 |
Popis: | In this study, precipitation behavior of the sigma phase with variations of the Ni and Mn in superaustenitic stainless steel weld metal was evaluated focused on microstructure and thermodynamic analysis. Experiments were conducted with variation of Ni and Mn based on a 23Cr-17Ni-6Mo superaustenitic stainless steel weld. And GTAW welding was performed on the casted specimens for simulating the weld metal. The weld metal consisted of γ-dendrite and an amount of sigma phases at interdendritic boundaries. And the sigma phase fraction showed decreasing behavior inversely according to addition of the Ni and Mn in the weld metal. From the microstructural analysis, the Ni addition induced increase of Mo content in the sigma phase, which caused the Mo depletion zone around the sigma phase. Whereas, the Mn addition induced replacement of Mo in sigma phase by Mn, so that the Mo depletion zone was not formed. Also, from the Thermo-Calc analysis, it was revealed that Ni addition caused increase of Mo activity, which induced Mo clustering in the sigma phase, while the Mn addition showed opposite effect of the Mo activity. |
Databáze: | OpenAIRE |
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