Advertisement

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

Abstract

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.

Keywords

aqueous corrosion copper tube corrosion intergranular attack 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    J.L. McDougall and M.E. Stevenson: “Stress Corrosion Cracking in Copper Refrigerant Tubing,”J. Failure Anal. Prevent., 2005,5(1), pp. 13–17.CrossRefGoogle Scholar
  2. 2.
    M.E. Stevenson, M.E. Barkey, and J.L. McDougall: “Stresses in Bent Copper Tubing: Application to Fatigue and Stress-Corrosion Cracking Failure Mechanism,”J. Failure Anal. Prevent., 2005,5(6), pp. 25–29.CrossRefGoogle Scholar
  3. 3.
    D.H. Duffner: “Air Conditioner Failure Investigation— Intergranular Cracking in a Pure Copper Condenser Tube,”J. Failure Anal. Prevent., 2005,5(1), pp. 79–85.CrossRefGoogle Scholar
  4. 4.
    R. Lane: “Under the Microscope: Understanding, Detecting, and Preventing Microbiologically Influenced Corrosion,”J. Failure Anal. Prevent., 2005,5(5), pp. 33–38.Google Scholar
  5. 5.
    R.A. Clark and D.R. Clark: “Microbiologically Influenced Corrosion in Hydronic Heating Systems,”J. Failure Anal. Prevent., 2004,4(4), pp. 38–42.CrossRefGoogle Scholar
  6. 6.
    “Copper and Copper Alloys: Seamless Round Tubes for General Purposes,” EN 12449:1999, European Committee for Standardization (CEN), Brussels, Belgium.Google Scholar

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

Personalised recommendations