Advertisement

Journal of Materials Science

, Volume 26, Issue 6, pp 1605–1608 | Cite as

Corrosion, erosion-corrosion, and the flexural strength of WC-Co hardmetals

  • W. J. Tomlinson
  • I. D. Molyneux
Papers

Abstract

The corrosion of commercial hardmetals containing 6, 8 and 10% Co with small additions of Cr3C2 and VC, in solutions of pH 1, 3, 5 and 10, and in a cutting fluid of pH 8.6, has been investigated using weight loss, atomic absorption spectroscopy, and metallographic techniques. For a surface area 420 mm2, at 20°C, the amount of cobalt dissolved in pH 5 and 10 solutions was less than 0.05 mg per day and in the cutting fluid was less than 0.05 mg in 7 days. Salt in the water increased the corrosion rate in the pH 10 solution by over five times. Corrosion was highest in the hardmetal containing VC. Corrosion in a pH 1 solution at 20 °C for 24 h (weight loss about 1 mg) did not affect the mean strength of the hardmetals. Erosion by alumina balls during corrosion increased the corrosion rate in the pH 1 solution by 16 to 29 times, formed a thick layer of WC denuded of cobalt, and reduced the strength of the eroded-corroded hardmetals by 0.54 to 0.76 times.

Keywords

Polymer Alumina Spectroscopy Cobalt Atomic Absorption 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    S. Ekemar, L. Lindholm and T. Hartzell, Refractory and Hard Metals 1 (1982) 37.Google Scholar
  2. 2.
    E. Kny and L. Schmid, ibid. 6 (1987) 145.Google Scholar
  3. 3.
    M. H. Ghandehar, J. Electrochem. Soc. 127 (1980) 214.CrossRefGoogle Scholar
  4. 4.
    J. B. Fink, S. A. Hoering and J. L. Griffith, Wear 108 (1986) 97.CrossRefGoogle Scholar
  5. 5.
    G. D. Mohan and B. E. Klamechi, ibid. 74 (1981) 85.CrossRefGoogle Scholar
  6. 6.
    W. J. Tomlinson and C. R. Linzell, J. Mater. Sci. 23 (1988) 914.CrossRefGoogle Scholar
  7. 7.
    W. J. Tomlinson and N. J. Ayerst, ibid. 24 (1989) 2348.CrossRefGoogle Scholar
  8. 8.
    E. Mosher, L. Peterson and R. Skold, Mater. Perf. 25 (1987) 38.Google Scholar
  9. 9.
    M. Pourbaix, “Atlas of Electrochemical Equilibria in Aqueous Solutions”, (Pergamon, London, 1966).Google Scholar

Copyright information

© Chapman and Hall Ltd. 1991

Authors and Affiliations

  • W. J. Tomlinson
    • 1
  • I. D. Molyneux
    • 1
  1. 1.Department of MaterialsCoventry PolytechnicCoventryUK

Personalised recommendations