Graphene oxide coating for improved corrosion resistance of NdFeB magnets

Authors

  • Mohsin Ali Raza University of Punjab
  • Akhlaq Ahmad
  • Faizan Ali Ghauri
  • Abdur Rehman
  • Rafiq Ahmad

DOI:

https://doi.org/10.24949/njes.v10i1.200

Keywords:

NdFeB, Electrophoretic deposition, Coating, Corrosion, Graphene oxide

Abstract

Electrophoretic deposition (EPD) of graphene oxide (GO) was carried out on Neodymium iron boron (NdFeB) magnets to study its potential as corrosion resistant coating. GO was produced from powder graphite by Hummers method. The GO was obtained by sonicating graphite oxide/water suspension and GO coatings were deposited on NdFeB magnets by making magnets anode in EPD process and by keeping voltage 10 V and time of deposition 1-2 min. GO and GO coating morphology and structure were studied by atomic force microscopy and x-ray diffraction, respectively. Electrophoretically deposited GO coatings on NdFeB were fairly uniform with some porosity. Potentiodynamic polarization and electrochemical impedance spectroscopy were used to study corrosion behavior of the GO coatings. GO coating reduced the corrosion rate of NdFeB by three times than the bare metal. The results show that GO coatings offer excellent corrosion resistant to NdFeB magnets in 3.5 % NaCl solution.

Author Biographies

Mohsin Ali Raza, University of Punjab

Department of Metallurgy & Materials Engineering

 Assistant Professor

Abdur Rehman

 

 

References

Geim, A.K. and K.S. Novoselov, The rise of graphene. Nature materials, 2007. 6(3): p. 183-191.

Nair, R., et al., Fine structure constant defines visual transparency of graphene. Science, 2008. 320(5881): p. 1308-1308.

Bunch, J.S., et al., Impermeable atomic membranes from graphene sheets. Nano letters, 2008. 8(8): p. 2458-2462.

Sutter, E., et al., Monolayer graphene as ultimate chemical passivation layer for arbitrarily shaped metal surfaces. Carbon, 2010. 48(15): p. 4414-4420.

Chen, S., et al., Oxidation resistance of graphene-coated Cu and Cu/Ni alloy. ACS nano, 2011. 5(2): p. 1321-1327.

Ghandehari, M.H., Rare earth-iron-boron permanent magnets with enhanced coercivity. 1988, Google Patents.

Tokuhara, K. and S. Hirosawa, Corrosion resistance of Nd‐Fe‐B sintered magnets. Journal of Applied Physics, 1991. 69(8): p. 5521-5523.

Chang, K.E. and G.W. Warren, The effect of absorbed hydrogen on the corrosion behavior of NdFeB alloys. Magnetics, IEEE Transactions on, 1995. 31(6): p. 3671-3673.

Schultz, L., et al., Corrosion behaviour of Nd–Fe–B permanent magnetic alloys. Materials Science and Engineering: A, 1999. 267(2): p. 307-313.

Attanasio, S. and R. Latanision, Corrosion of rapidly solidified neodymium-iron-boron (Nd Fe B) permanent magnets and protection via sacrificial zinc coatings. Materials Science and Engineering: A, 1995. 198(1): p. 25-34.

Rada, M., et al., Corrosion studies on highly textured Nd–Fe–B sintered magnets. Journal of alloys and compounds, 2006. 415(1): p. 111-120.

El-Moneim, A. and A. Gebert, Electrochemical characterization of galvanically coupled single phases and nanocrystalline NdFeB-based magnets in NaCl solutions. Journal of applied electrochemistry, 2003. 33(9): p. 795-805.

Besra, L. and M. Liu, A review on fundamentals and applications of electrophoretic deposition (EPD). Progress in materials science, 2007. 52(1): p. 1-61.

He, W., et al., Electrophoretic deposition of graphene oxide as a corrosion inhibitor for sintered NdFeB. Applied Surface Science, 2013. 279: p. 416-423.

Hummers Jr, W.S. and R.E. Offeman, Preparation of graphitic oxide. Journal of the American Chemical Society, 1958. 80(6): p. 1339-1339.

Daniel R. Dreyer, S.P., Christopher W. Bielawski, Rodney S. Ruoff, The chemistry of graphene oxide. The Royal Society of Chemistry, 2010. 39: p. 228–240.

Downloads

Published

2017-02-21

Issue

Section

Engineering Sciences