Journal of Applied Electrochemistry

, Volume 17, Issue 2, pp 270–282 | Cite as

Controlled nucleation and growth in chromium electroplating from molten LiCl-KCl

  • T. Vargas
  • D. Inman


The relationships between the electrochemical parameters (which can be controlled) and the resulting structures of chromium electrodeposits obtained by electrolysing chromous chloride (CrCl2) dissolved in the LiCl-KCl eutectic have been established. The electrodeposition of chromium under ordinary potentiostatic conditions leads to pure chromium but this is not in a form to provide an adequate protective coating as it is difficult to avoid dendrite formation and low initial coverage together. These limitations can be overcome by the sequential use of a high overpotential pulse to initiate good coverage and continuing electrodeposition at low overpotential to minimize dendrite formation.

The structures and morphologies of chromium electroplates were optimized. The good protective coatings that resulted were adherent, coherent and reasonably free of cracks and pores. The macro-and microthrowing powers of the bath were excellent and the high purity of the chromium electroplates led to low (130–280 HV) measured microhardness.


Chloride Chromium High Purity Protective Coating Good Coverage 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    D. Inman and S. H. White,J. Appl. Electrochem. 8 (1978) 375.Google Scholar
  2. [2]
    R. S. Sethi,9 (1979) 411.Google Scholar
  3. [3]
    A. H. Sully, ‘Metallurgy of the rarer metals — 1: Chromium’, Butterworths Scientific Publications, London (1954).Google Scholar
  4. [4]
    K. P. V. Lei, J. M. Hiegel and T. A. Sullivan,J. Less Common Metals 27 (1972) 353.Google Scholar
  5. [5]
    D. Inman, J. C. L. Legey and R. Spencer,J. Electroanal. Chem. 61 (1975) 289.Google Scholar
  6. [6]
    R. E. Cains Jr. and N. J. Grant,Trans. AIME 230 (1964) 1156.Google Scholar
  7. [7]
    A. K. Suri and C. K. Gupta,Surf. Technol. 5 (1977) 271.Google Scholar
  8. [8]
    T. Vargas, PhD Thesis, Imperial College, London (1984).Google Scholar
  9. [9]
    T. Vargas and D. Inman, to be published.Google Scholar
  10. [10]
    T. Vargas and D. Inman, to be published.Google Scholar
  11. [11]
    J. O'M. Bockris, G. J. Hills, D. Inman and L. Young,J. Sci. Instr. 33 (1956) 438.Google Scholar
  12. [12]
    F. M. Dorsey,Ind. Eng. Chem. 20 (1928) 1094.Google Scholar
  13. [13]
    A. R. Despic and K. I. Popov, in ‘Modern Aspects of Electrochemistry’, Vol. 7 (edited by B. E. Conway and J. O'M. Bockris), Butterworth & Co. Ltd, London (1972) p. 199.Google Scholar
  14. [14]
    K. I. Popov, M. D. Maksimovic and J. D. Trnjancev,J. Appl. Electrochem. 11 (1981) 239.Google Scholar
  15. [15]
    N. A. Gjostein, in ‘Metal Surfaces’, American Society for Metals, Metals Park, Ohio (1963) chap. 4.Google Scholar
  16. [16]
    T. B. Reddy,J. Electrochem. Soc. 113 (1966) 117.Google Scholar
  17. [17]
    M. P. Hill, D. Inman and T. Vargas, UK Patent Application No. 8403184, 8 Feb. 1984.Google Scholar
  18. [18]
    A. H. Sully, ‘Chromium Plating’, Robert Draper, Teddington, Middlesex, UK (1954), chap. 3.Google Scholar
  19. [19]
    D. Inman, T. Vargas, S. Duan and P. Dudley, in ‘Proceedings of 4th Int. Symposium on Molten Salts’, New Jersey, The Electrochemical Society Inc. (1984) pp. 545.Google Scholar
  20. [20]
    A. R. Despic and K. I. Popov,J. Appl. Electrochem. I (1971) 275.Google Scholar
  21. [21]
    F. A. Lowenheim, in ‘Modern Electroplating’, John Wiley & Sons Inc., New York (1974) chap. 1.Google Scholar
  22. [22]
    P. Morriset, J. W. Oswald, C. R. Draper and R. Pinner, ‘Chromium Plating’, Robert Draper, Teddington, Middlesex, UK (1954).Google Scholar
  23. [23]
    A. Brenner, P. Burkhead and C. Jennings,J. Res. Nat. Bur. Standards 40 (1948) 31.Google Scholar
  24. [24]
    J. Wurm,Met. Finish. 78 (1980) 37.Google Scholar
  25. [25]
    M. P. Hill, private communication (and seeJ. Appl. Electrochem. 17 (1987) 283.Google Scholar

Copyright information

© Chapman and Hall Ltd. 1987

Authors and Affiliations

  • T. Vargas
    • 1
  • D. Inman
    • 1
  1. 1.Department of MaterialsImperial CollegeLondonUK

Personalised recommendations