Metallography of CB2 Steel Used for Cast Turbine Components

Abstract:

Steel CB2 developed in frame of the COST actions belongs to the most promising steel for production of cast turbine components working at ultra-supercritical steam conditions. VZÚ Plzeň has participated on assessment of original trial melt CB2 as well as on testing of samples coming from one of pilot valves produced of steel CB2 in full scale. Recently VZÚ Plzeň has cooperated with Doosan Škoda Power in development of weld processes of advanced power energy steels including steel CB2. This contribution deals with a comparison of properties of the steel CB2 produced by four various steelmakers from point of view of their microstructure in relation with their mechanical and creep resistant properties. Evaluation is focused on chemical heterogeneity, porosity, content of non-metallic inclusions, in particular on an occurrence of coarse NB, microstructure and substructure using methods of light and electron microscopy.

• Periodical: Materials Science Forum (Volume 782)
• Pages: 179-185
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.782.179
• Online since: April 2014
• Authors: Josef Kasl, Dagmar Jandová
• Keywords: Casts, Creep Resistant Steel CB2, Creep Test, Electron Microscopy, Light Microscopy, Microstructure

References

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