Development of a New Electrodeposition Process for Plating of Zn-Ni-X (X5Cd, P) Alloys I. Corrosion Characteristics of Zn-Ni-Cd Ternary Alloys
نویسندگان
چکیده
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 NiSO4 1 0.2 M ZnSO4 bath in the presence of 0.015 M CdSO4 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%) CdSO4 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. © 2000 The Electrochemical Society. S0013-4651(99)11-016-4. All rights reserved.
منابع مشابه
Development of a New Electrodeposition Process for Plating of Zn-Ni-X (X = Cd, P) Alloys - Permeation Characteristics of Zn-Ni-Cd Ternary Alloys
It is shown that an electrodeposited Zn-Ni-Cd alloy coating produced from sulfate electrolyte inhibits the discharge of hydrogen on carbon steel. The newly developed ternary alloys have approximately ten times higher corrosion resistance when compared to a Zn-Ni alloy. Hydrogen permeation characteristics of Zn-Ni-Cd alloy coatings were studied and compared with those of a bare and a Zn-Ni alloy...
متن کاملDevelopment of a New Electrodeposition Process for Plating of Znâ•’Niâ•’X (X = Cd, P) Alloys: I. Corrosion Characteristics of Znâ•’Niâ•’Cd Ternary Alloys
متن کامل
Electroplating and characterization of Zn–Ni, Zn–Co and Zn–Ni–Co alloys
a r t i c l e i n f o Zn–Ni, Zn–Co and Zn–Ni–Co coatings were electrodeposited on mild steel from an acidic chloride bath containing p-aminobenzenesulphonic acid (SA) and gelatin. These additives changed the phase content in the coatings, most likely as a result of their adsorption at the surface of the cathode. The effect of gelatin was more pronounced than that of SA. The Faradaic efficiency ...
متن کاملCharacterisation and Corrosion Performance of MultilayerNano Nickel Coatings on AZ31 Magnesium Alloy
Ni-P and Ni layers multilayer coatings were applied to AZ31 magnesium alloy utilizing electroless and electrodeposition procedures. The aim of the project was to decrease cracks and increase corrosion resistance of the coatings. In order to compare the coatings, the effect of single layer electroless Ni-P coatings with different thicknesses was also investigated. The microstructure and phase co...
متن کاملA Novel Electrodeposition Process for Plating Zn-Ni-Cd Alloys
Zn-Ni-Cd alloy was electrodeposited from an alkaline electrolytic bath under potentiostatic conditions. Bath analyses using a pH concentration diagram reveal that addition of a complexing agent is essential to maintain the bath stability. Introduction of a low concentration of CdSO4 reduces the anomalous nature of the Zn-Ni deposit. Deposits obtained from the electrolytic bath which contains 60...
متن کامل