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Journal of Failure Analysis and Prevention

, Volume 14, Issue 1, pp 10–12 | Cite as

Failure of a Secondary Superheater Tube in a 140-MW Thermal Power Plant

  • Atanu Saha
  • A. K. Shukla
Case History---Peer-Reviewed

Abstract

This investigation was conducted to determine the cause of failure of a welded joint of a secondary superheater tube from a 140-MW thermal power plant. Chemical analyses along with detailed optical microscopic examination of a secondary superheater tube were carried out to predict the probable cause of failure. Microstructure of the secondary superheater tube welded between austenitic stainless steel to low alloy steel revealed presence of a thin layer of metal carbide along the weld interface which eventually led to intergranular cracking at austenite grain boundaries. It was concluded that the formation of brittle carbide layer was due to migration of carbon at elevated temperature led to failure of the tube.

Keywords

Weld Superheater tube HAZ Failure 

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Copyright information

© ASM International 2013

Authors and Affiliations

  1. 1.NDT and Metallurgy GroupCSIR- Central Mechanical Engineering Research InstituteDurgapurIndia

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