Properties of Welded Joints on Superheater Coils Made from New Generation High Alloy Martensitic Steels Connected to Austenitic Creep-Resisting Steels and Supper Alloy Grades, for Supercritical Parameters

Abstract:

The continuously developing power generation sector, including boilers with supercritical parameters, requires applications of new creep-resistant steel grades for construction of boilers steam superheater components. Therefore, this paper contains selected information, results of the research and implementation process including: - evaluation, comparison of requested properties of base material and welded joints, such as tensile strength, impact strength and technological properties, - destructive examinations with evaluation of welded joints and HAZ structure and hardness distribution, - influence of manufacturing process in large boilermaker conditions and after simulated operation. A new creep-resistant steels to be used, in order to comply with the operational requirements, as to assure the appropriate reliability and safety of the boiler equipment in operation process. This document presents a simplified analysis of martensitic steels from group 9-12% Cr (T91, T92, HCM12A, VM12) and austenitic steels Cr-Ni (TP347FG, SUPER 304H, HR3C), having the chemical composition as presented in tables 1 and 2, which are to be applied for steam superheater components.

• Periodical: Advanced Materials Research (Volume 278)
• Pages: 466-471
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.278.466
• Online since: July 2011
• Authors: Jerzy Pasternak, Janusz Dobrzanski
• Keywords: Corrosion Resistance, Creep Resistance, Steel Structure Stability, Technological Property, Welding

References

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DOI: 10.1179/174892406x173657

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