Protection of Mg Alloys against Galvanic and Other Forms of Corrosion


Article Preview

Galvanic corrosion is a particularly important form of corrosion for Mg alloys used in automobiles. Our research work focuses on corrosion protection using cost-effective Cr-free coatings. The top-tanking coatings are found to be effective in preventing general corrosion; some of these coatings are also good for reducing galvanic corrosion and stress corrosion. A practical approach for mitigating galvanic corrosion is to increase the electrolytic resistance between the coated steel and the Mg surfaces. This has been demonstrated in the case of a conversion coating plus a powder coat applied on the surface of a magnesium alloy and in the case of a thin Mylar isolation layer installed between the Mg and the steel surfaces.



Materials Science Forum (Volumes 488-489)

Edited by:

W.Ke, E.H.Han, Y.F.Han, K.Kainer and A.A.Luo




W. Y. Zheng et al., "Protection of Mg Alloys against Galvanic and Other Forms of Corrosion", Materials Science Forum, Vols. 488-489, pp. 787-792, 2005

Online since:

July 2005




[1] J.E. Hillis and R.W. Murray 14th International Die Casting Congress and Exposition, Toronto, Canada, Paper No. G-T87-003, (1987).

[2] Duan, H; Wang, L; Cai, Q; Zhang, S; Wei, B, China Mechanical Engineering. Vol. 14, no. 20, pp.1789-1792. 25 Oct. (2003).

[3] R. Osborne, G. Cole, B. Cox and P. Penrod, USCAR Project on Magnesium Structural Castings, Proc. IMA 2000 Magnesium Conference, Vancouver, Canada, 21-23 May, 2000, pp.1-5.

[4] W. Zheng, C. Derushie, R. Zhang and J. Lo, Protection of Mg Alloys for Structural Applications in Automobiles, SAE Paper # 2004-01-0133, SAE.


[5] P. Bakke, S. Sannes and D. Albright, Effects of Ni, Cu, Si and Co on the Corrosion Properties of Permanent Mould Cast Medallions and Die Cast Plates of Magnesium Alloy AZ91, SAE Technical Paper No. 1999-01-0926, SAE, Warrendale, PA, USA.


[6] D. Davis, Industrial Paint & Powder (USA), vol. 74, No. 6, June, 1998, pp.34-36. (b) P. Kurze, T. Singe and J. Diesing, "Corrosion protection of magnesium materials (Original Title: Korrosions-schutz von Magnesium-Werkstoffen. ), Metalloberf-lache [Metalloberflache], vol. 54, No. 9, pp.22-24, Sept. (2000).

[7] http: /www. tagnite. com.

[8] T. Korner, R. Seidel and U. Juptner, New possibilities for magnesium: Chrome-free surface treatments for magnesium, Metalloberflache (Germany), vol. 55, No. 1, p.20, Jan. (2001).

[9] J.A. Johnston and S. Smith, Proc. Alliance for the Polyurethanes Industry (API) Conference, Salt Lake City, Utah, October 13-16, (2002).

[10] G. Wang, K. Stwart, R. Berkmortel and J.I. Skar, Corrosion Prevention for External Magnesium Automotive Components, SAE Technical paper No. 2001-01-0421, SAE, Warrendale, PA, USA.


[11] G. Gao, G. Cole, M. Ricketts, J. Balzer and P. Frantzeskakis, Effects of fastener surface on galvanic corrosion of automotive magnesium components, Magnesium 2000: Second International Conference on Magnesium Science & Technology, Dead Sea, Israel Feb. 22-24, 2000, Proceedings of the Second Israeli International Conference on Magnesium Science & Technology, pp.321-338.


[12] D. Hawke and T. Ruden, Galvanic compatibility of coated steel fasteners with magnesium, Hydro Magnesium, Publ: Society of Automotive Engineers, 400 Commonwealth Dr., Warrendale, PA 15096, USA, 1995 SAE Transactions: Journal of Materials & Manufacturing, vol. 104, 1995, pp.358-362.


[13] En-Hou Han, Wanqiu Zhou, Dayong Shan and Wei Ke, Chemical Conversion Coating on AZ91D and its Corrosion Resistance, in Magnesium Technology 2004, Edited by Alan Luo, TMS (2004).