Open Access Open Access  Restricted Access Subscription or Fee Access

Electrolytic Deposition of Zn–Ni Alloy from Acidic Sulphate Bath and Their Characterization

R. S. Bhat, J. Nayak, A. C. Hegde

Abstract


A bath containing ZnSO4.7H2O, NiSO4.7H2O, thiamine hydrochloride (THC) and citric acid (CA) has been proposed. Bright Zn–Ni alloy coatings were developed galvanostatically onto mild steel (MS) and their corrosion resistance and other physical properties were studied. THC was found to improve the brightness and homogeneity of the deposit. The dependency of bath composition, current density (c.d.), pH and temperature, agitation on wt.% Ni were tested. Deposition was carried out under different c.d. and molar ratio of [Ni+2]/[Zn+2]. No transition c.d., at which codeposition behaviour changed from anomalous to normal type, was detected. Studies of the factors such as temperature, agitation, pH and [Ni+2]/[Zn+2] which influence the wt.% Ni in the deposit were made. Influence of wt.%Ni on corrosion resistance, hardness, adhesion and glossiness were studied. The wt.% Ni in the deposit was determined calorimetrically and cross-examined by EDX analysis. The morphological variation in deposit patterns with c.d. were examined by Scanning Electron Microscopy (SEM). Good corrosion resistance at optimized c.d. (3.0 A/dm2) is attributed to the capacitive reactance at the interface, evidenced by Nyquist plot having large polarization resistance. The XRD analysis was carried out to identify the phase structures of the deposits.

Full Text:

PDF

References


Bajat J.B., Kacarevic-Popovic Z., Miskovic-Stankovic V.B., et al. Corrosion behaviour of epoxy coatings electrodeposited on galvanized steel and steel modified by Zn-Ni alloys, Prog Org Coat. 2000; 39: 127–35p.

Brooks I., Erb U. Hardness of electrodeposited microcrystalline and nanocrystalline γ-phase Zn-Ni alloys, Scr Mater. 2001; 44(5): 853–8p.

Muller C., Sarret M., Benballa M. Complexing agents for a Zn-Ni alkaline bath, J Electroanal Chem. 2002; 519: 85–92p.

Shivakumara S., Manohar U., Arthoba N.Y., et al. “Influence of additives on electrodeposition of bright Zn–Ni alloy on mild steel from acid sulphate bath, Bull Mater Sci. 2007; 30: 455–62p.

Roventi G., Fratesi R., Della Guardia R.A., et al. Normal and anomalous codeposition of Zn-Ni alloys from chloride bath, J Appl Electrochem. 2000; 30: 173–9p.

Ebothe J., Hiane M. Coating and active surface of Ni-Zn alloys studied by atomic force microscopy, Appl Surf Sci. 2000; 183: 93– 102(10)p.

Ashassi-Sorkhabi H., Hagrah A., Parvini-Ahmadi N., et al. Zinc-nickel alloy coatings electrodeposited from a chloride bath using direct and pulse current, Surf Coat Technol. 2001; 140: 278–82p.

Koura N., Suzuki Y., Idemoto Y., et al. Electrodeposition of Zn–Ni alloy from ZnCl2–NiCl2–EMIC and ZnCl2–NiCl2–EMIC–EtOH ambienttemperature molten salts, Surf Coat Technol. 2003; 169–170: 120–3p.

Wang Z.-L., Yang Y.X, Chen Y.-R. A study on electroplating of ZincNickel with HEDP, J Corros Sci Eng. 2005; (7): 8–14p.

Gomez E., Alcobe X., Valles E. Characterisation of zinc-cobalt alloy phases obtained by electrodeposition, J Electroanal Chem. 2001; 505(1-2): 54–61p.

Ramanauskas R., Quintana P., Maldonado L., et al. Corrosion resistance and microstructure of electrodeposited Zn and Zn alloy coatings, Surf Coat Technol. 1997; 92: 16–21p.

Abou-Krisha M.M. Electrochemical studies of zinc-nickel codeposition in sulphate bath, Appl Surf Sci. 2005; 252: 1035–48p.

Pech-Canul M.A., Ramanauskas R., Maldonado L. An electrochemical investigation of passive layers formed on electrodeposited Zn and Zn alloy coatings in alkaline solutions, Electrochim Acta. 1997; 42(2): 255–60p.

Brenner A. Electrodeposition of Alloys-Principles and Practice. Vol. 1 & 2. New York: Academic Press; 1963.

Pardhasaradhy V. Practical Electroplating Hand Book. Prentice Hall Incl; 1989.

Abou-Krisha M.M., Assaf F.H., Toghan A.A. Electrodeposition of Zn-Ni alloys from sulfate bath, J Solid State Electrochem. 2007; 11: 244–52p.

Orinakova R., Turonova A., Kladekova D., et al. Recent developments in the electrodeposition of nickel and some nickel-based alloys, J Appl Electrochem. 2006; 36: 957–72p.

Kanani N. Electroplating: Basic Principles, Processes and Practice. Berlin, Germany: Elsevier Ltd; 2006.

Horkans J. Effect of plating parameters on electrodeposited NiFe, J Electrochem Soc. 1981; 128(1): 45–9p.

Trejo G., Ortega R., Meas Y., et al. Effect of benzylideneacetone on the electrodeposition mechanism of ZnCo alloy, J Appl Electrochem. 2003; 33: 373–9p.

Felloni L., Fratesi R., Quadrini E., et al. Electrodeposition of zinc-nickel alloys from chloride solution, J Appl Electrochem. 1987; 17: 574–82p.




DOI: https://doi.org/10.37628/jcep.v2i2.195

Refbacks

  • There are currently no refbacks.