Development of a new electrodeposition process for plating of Zn-Ni-X (X=Cd, P) alloys. 1. Corrosion characteristics of Zn-Ni-Cd ternary alloys
A new Zn-Ni-Cd plating process was developed which offers a unique way of controlling and optimizing the Ni and Cd contents in the final deposit. Zinc-nickel-cadmium alloy was deposited from a 0.5 M NiSO{sub 4} + 0.2 M ZnSO{sub 4} bath in the presence of 0.015 M CdSO{sub 4} and 1 g/L nonyl phenyl polyethylene oxide. Using this process a Zn-Ni-Cd ternary alloy, with a higher nickel content as compared to that obtained from conventional Zn-Ni baths, was synthesized. The Zn-Ni-Cd alloy coatings deposited from an electrolyte containing 0.015 M (0.3%) CdSO{sub 4} has a Zn to Ni ratio of 2.5:1. The increase in nickel content accounts for the observed decrease in the corrosion potential to a value lower than that of Cd but higher than the corrosion potential of iron. The coatings have superior corrosion resistance and barrier properties than the typical Zn-Ni and cadmium coatings. Polarization studies and electrochemical impedance spectroscopy analysis on Zn-Ni-Cd coatings show a barrier resistance that is ten times higher than that of a conventional Zn-Ni coating.
- Research Organization:
- Univ. of South Carolina, Columbia, SC (US)
- OSTI ID:
- 20080578
- Journal Information:
- Journal of the Electrochemical Society, Vol. 147, Issue 5; Other Information: PBD: May 2000; ISSN 0013-4651
- Country of Publication:
- United States
- Language:
- English
Similar Records
Characterization of hydrogen permeation through a corrosion-resistant zinc-nickel-phosphorus alloy
Study of electroless Ni-W-P alloy coating on martensitic stainless steel