Corrosion Behavior of Electrodeposited Nickel Coatings on AZ91 Mg Alloy

مهندسی متالورژی و مواد

Article 1, Volume 26, Issue 2 - Serial Number 12, September 2015, Pages 1-10   

Document Type: Original Articles

DOI: 10.22067/ma.v26i2.28249

Authors

Arman Zarebidaki^{* 1}; Mohammad-Reza Aboutalebi²; hassan mahmoudikohani¹

¹Department of Metallurgical Engineering, Yazd Branch, Islamic Azad University, Yazd, Iran.

²School of Metallurgy and Materials Engineering, Iran University of Science and Technology, 16846-13114, Tehran, Iran.

Abstract

In this study, nickel was electrodeposited onto the surface of AZ91 Mg alloy and its corrosion resistance was compared with those of AZ91 Mg alloy and pure nickel using polarization and electrochemical impedance spectroscopy (EIS) experiments in a 3.5 wt.% NaCl solution. The structure of coating was investigated by means of X-ray diffraction, and the specimen’s morphology and the coating’s chemical composition were analyzed using scanning electron microscope (SEM). The results showed that the coating has a nano-crystalline structure with the average grain size of 95 nm. The results of corrosion tests showed a decrease in the corrosion current density from 2.5×10-4 A.cm-2 for the uncoated sample to 1.5×10-5 A.cm-2 for the coated specimen, as well as an increase in the corrosion potential.

Keywords

AZ91 Mg alloy; Nickel electrodeposition; corrosion; EIS; Polarization

References

Iranipour, N., AzariKhosroshahi, R., ParviniAhmadi, N., "A study on the electroless Ni–P deposition on WE43 magnesium alloy", Surface and Coatings Technology, Vol. 205, pp. 2281-2286, (2010).

2. Elsentriecy, H.H., Azumi, K.,"Electroless Ni–P Deposition on AZ91 D Magnesium Alloy Prepared by Molybdate Chemical Conversion Coatings", Journal of Electrochemical Society,Vol.156, pp. D70-D77, (2009).

3. Zhang, W.X., Jiang, Z.H., Li, G.Y., Jiang, Q.,Lian, J.S., "Electroless Ni–Sn–P coating on AZ91D magnesium alloy and its corrosion resistance, Surface and Coatings Technology", Vol.202, pp. 2570-2576, (2008).

4. Gu, C., Lian, J., He, J., Jiang, Z., Jiang, Q.,"High corrosion-resistance nanocrystalline Ni coating on AZ91D magnesium alloy", Surface and Coatings Technology, Vol.200, pp. 5413-5418, (2006).

5. Ambat, R., Zhou, W.,"Electroless nickel-plating on AZ91D magnesium alloy: effect of substrate microstructure and plating parameters", Surface and Coatings Technology, Vol.179, pp. 124-134, (2004).

6. Huang, C.A., Wang, T.H., Weirich, T., Neubert, V., "A pretreatment with galvanostatic etching for copper electrodeposition on pure magnesium and magnesium alloys in an alkaline copper-sulfate bath", ElectrochimicaActa, Vol.53, pp. 7235-7241, (2008).

7. Li, G.Y., Lian, J.S., Niu, L.Y., Jiang, Z.H., Jiang, Q., "Growth of zinc phosphate coatings on AZ91D magnesium alloy", Surface and Coatings Technology, Vol.201, pp. 1814-1820, (2006).

8. ASTM Standard Designation B 480-88.

9. Spencer, L.F.,"Metal Finishing",Vol.68, p.32, (1970).

10. Sakata, Y.,"Electroless nickel plating directly on magnesium alloy die castings", 74th AESF Technical Conference,p.15, (1987).

11. Fairweather, W.A.,"Electroless nickel plating of magnesium", Transactions, Vol.75, pp. 113-117, (1997).

12. Brown, L.,"UK company leads the way in magnesium plating", Finishing, Vol.18, pp. 22-23, (1994).

13. Corley, P.J., "Magnesium magic", Finishing,Vol.19, p.26, (1995).

14. Zhu, Y., Yu, G., Hu, B., Lei, X., Yi, H., Zhang, J.,"Electrochemical behaviors of the magnesium alloy substrates in various pretreatment solutions", Applied Surface Science, Vol.256, pp. 2988-2994, (2010).

15. Huang, C.A., Wang, T.H., Weirich, T.,Neubert,V., "Electrodeposition of a protective copper/nickel deposit on the magnesium alloy (AZ31)", Corrosion Science, Vol.50, pp. 1385-1390, (2008).

16. Lee, J., Chung, W., Jung, U., Kim, Y., "Direct nickel electrodeposition on magnesium alloy in pyrophosphate electrolyte", Surface and Coatings Technology, Vol.205, pp. 4018-4023, (2011).

17. Tang, J., Azumi, K., "Effect of copper pretreatment on the zincate process and subsequent electroplating of a protective copper/nickel deposit on the AZ91D magnesium alloy", ElectrochimicaActa, Vol.56, pp. 8776-8782, (2011).

18. Birks, L.S., Friedman, H., "Particle size determination from x-ray line broadening", Journal of Applied Physics,Vol.17, pp. 687-692, (1946).

19. Gray, J.E., Luan, B., "Protective coatings on magnesium and its alloys - a critical review", Journal of Alloys and Compounds, Vol.336, pp. 88-113, (2002).

20. Bicelli, L.P., Bozzini, B., Mele, C., DUrzo, L., "A Review of Nanostructural Aspects of Metal Electrodeposition", International Journal of Electrochemical Science, Vol.3,pp. 356-408, (2008).

21. Liu, Y., Yu, S.-r., Liu, J.-d., Han, Z.-w., Yuan, D.-s., " Microstructure and wear resistance of electrodeposited Ni-SiO2 nano-composite coatings on AZ91HP magnesium alloy substrate", Transactions of Nonferrous Metals Society of China, Vol.21, Supplement 2, pp. s483-s488, (2011).

22. Mu, S., Li, N., Li, D., Xu, L., "Corrosion behavior and composition analysis of chromate passive film on electroless Ni-P coating", Applied Surface Science, Vol.256, pp. 4089-4094, (2010).

23. Jung, H., Alfantazi, A., "An electrochemical impedance spectroscopy and polarization study of nanocrystalline Co and Co–P alloy in 0.1 M H2SO4 solution", ElectrochimicaActa, Vol. 51, pp. 1806-1814, (2006).

24. Yao, Z., Jiang, Z., Wang, F., "Study on corrosion resistance and roughness of micro-plasma oxidation ceramic coatings on Ti alloy by EIS technique", ElectrochimicaActa, Vol. 52, pp. 4539-4546, (2007).

25. Mark, B.T., Orazem, E., "Electrochemical Impedance Spectroscopy", John Wiley & Sons, (2008).

26. Balaraju, J.N., Sankara Narayanan, T.S.N., Seshadri, S.K., "Electroless Ni–P composite coatings", Journal of Applied Electrochemistry,Vol. 33,pp. 807-816, (2003).

27. Liang, J., Srinivasan, P.B., Blawert, C., Dietzel, W., "Influence of chloride ion concentration on the electrochemical corrosion behaviour of plasma electrolytic oxidation coated AM50 magnesium alloy", ElectrochimicaActa, Vol.55, pp. 6802-6811, (2010).

28. Shreir, R.A.J. L.L., Burstein, G.T., " CORROSION", Butterworth-Heinemann, Great Britain, (1994).

29. Wang, L., Shinohara, T., Zhang, B.-P.,"Corrosion behavior of Mg, AZ31, and AZ91 alloys in dilute NaCl solutions", Journal of Solid State Electrochemistry, Vol.14, pp. 1897-1907, (2010).