The Effect of Cold Bending Process and Degradation at Boiler Conditions on the Properties of New Austenitic Creep Resistant Steel Super 304H for Boiler Super-Heaters Tubes

Abstract:

This paper is focused on evaluation of the plastic deformation effect, after the cold bending process for new austenitic material Super 304H designed for supercritical conditions. The aim of the project was to qualify the process of cold bending and then verify the properties of these bends in conditions approaching application. This paper presents the results of the plastic deformation effect on changes in the structure and mechanical properties at operating temperatures in corrosive environments coal combustion products and comparison to results before degradation. The tests were carried out on bends in two dimensions of tubes which are the most common sizes used in super-heaters for supercritical power plant boiler. The bends were produced by the method of cold bending on several bending radii in order to obtain information about the structure and behaviour of materials at various stages of deformation. To obtain reliable information tensile test, hardness test and metallographic examination were used on material from straight tubes of the bends and drawn parts before degradation and after degradation.

• Periodical: Materials Science Forum (Volume 891)
• Pages: 230-234
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.891.230
• Online since: March 2017
• Authors: Šárka Hermanová*, Ladislav Kander, Jakub Horváth
• Keywords: Austenitic Steels, Bends, Sigma Phase, Super-Heater Tubes

References

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DOI: 10.4028/www.scientific.net/msf.891.230

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