Metallurgical and Materials Transactions A

, Volume 43, Issue 5, pp 1477–1486

Phase Identification and Internal Stress Analysis of Steamside Oxides on Plant Exposed Superheater Tubes

Authors

    • Department of Mechanical EngineeringTechnical University of Denmark
  • Melanie Montgomery
    • Department of Mechanical EngineeringTechnical University of Denmark
    • Vattenfall A/S, Thermal Engineering Denmark
Symposium: Neutron and X-Ray Studies of Advanced Materials IV

DOI: 10.1007/s11661-011-0874-x

Cite this article as:
Pantleon, K. & Montgomery, M. Metall and Mat Trans A (2012) 43: 1477. doi:10.1007/s11661-011-0874-x

Abstract

During long-term, high-temperature exposure of superheater tubes in thermal power plants, various oxides are formed on the inner side (steamside) of the tubes, and oxide spallation is a serious problem for the power plant industry. Most often, oxidation in a steam atmosphere is investigated in laboratory experiments just mimicking the actual conditions in the power plant for simplified samples. On real plant-exposed superheater tubes, the steamside oxides are solely investigated microscopically. The feasibility of X-ray diffraction for the characterization of steamside oxidation on real plant-exposed superheater tubes was proven in the current work; the challenges for depth-resolved phase analysis and phase-specific residual stress analysis at the inner side of the tubes with concave surface curvature are discussed. Essential differences between the steamside oxides formed on two different steels typically applied for superheaters, ferritic-martensitic X20CrMoV12-1 and lean austenitic stainless steel TP347H, respectively, are revealed by X-ray diffraction.

Copyright information

© The Minerals, Metals & Materials Society and ASM International 2011