Journal of Failure Analysis and Prevention

, Volume 6, Issue 6, pp 8–12 | Cite as

Corrosion of a copper U-shaped heating element: Some morphological and microstructural observations

  • G. Pantazopoulos
  • G. Tsinopoulos
Case Histories


In this work, observations of the corrosion on a failed copper U-shaped tube, of 1 mm nominal thickness, are presented. This tube was subjected to severe corrosion and subsequent cracking after a month of operation as the heating element of an electrical boiler. Morphological and microstructural observations of the failure area as well as cross sections of the corroded copper tube are presented. Moreover, the chemical composition of the material and the principal physicochemical characteristics of the tap water used for boiler operation were determined in the context of the failure investigation. The quality of the water used for boiler operation was a significant factor influencing the heating element efficiency and reliability. Hard water with high electrical conductivity accelerated salt precipitation and led to the corrosion and premature failure of the components.


aqueous corrosion copper tube corrosion intergranular attack 


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Copyright information

© ASM International - The Materials Information Society 2006

Authors and Affiliations

  • G. Pantazopoulos
    • 1
  • G. Tsinopoulos
    • 1
  1. 1.Quality Control and Quality Assurance DepartmentHALCOR S.A. Metal WorksAthensGreece

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