Effect of diffusion alloying time on corrosion resistance and surface conductivity of niobium-alloying-modified AISI430 stainless steel for DFAFC bipolar plate
Anti-Corrosion Methods and Materials
ISSN: 0003-5599
Article publication date: 20 February 2019
Issue publication date: 22 February 2019
Abstract
Purpose
The purpose of this study is to improve the surface electrical conductivity and corrosion resistance of AISI430 stainless steel (430 SS) as bipolar plates for direct formic acid fuel cell (DFAFC).
Design/methodology/approach
The niobium diffusion layers have been successfully synthesized on 430 SS substrate by the plasma surface diffusion alloying technique under different diffusion alloying time.
Findings
The surface morphology of Nb-modified 430 SS prepared under the diffusion alloying time of 2 h is more homogeneous, relatively sleek and compact without surface micropore and other common surface blemishes. The potentiostatic and potentiodynamic polarization measurements manifest that Nb-modified 430 SS prepared under the diffusion alloying time of 2 h enormously ameliorate the corrosion resistance of bare 430 SS compared with other Nb-modified 430 SS samples and its corrosion current density is maintained at −1.4 µA cm−2 in simulated anodic environment of DFAFC (0.05 M H2SO4 + 2 ppm HF + 10 M formic acid at 50 °C).
Originality/value
The effect of diffusion alloying time on the corrosion resistance and surface conductivity of Nb-modified 430 SS has been carefully studied. The Nb-modified 430 SS samples prepared at the diffusion alloying time of 2 h have the best surface electrical conductivity and corrosion resistance in the simulated anodic environment of DFAFC.
Keywords
Acknowledgements
This work was supported by the National Natural Science Foundation of China (Grants 51479019 and 21476035) and Fundamental Research Funds for the Central Universities (3132016341).
Citation
Han, J., Zhang, H., Sun, J., Zhao, W. and Cui, J. (2019), "Effect of diffusion alloying time on corrosion resistance and surface conductivity of niobium-alloying-modified AISI430 stainless steel for DFAFC bipolar plate", Anti-Corrosion Methods and Materials, Vol. 66 No. 2, pp. 222-229. https://doi.org/10.1108/ACMM-08-2018-1982
Publisher
:Emerald Publishing Limited
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