Microstructure and mechanical properties of electro-brush plated Fe/MWCNTs composite coatings

Fe/MWCNTs (multi walled carbon nanotubes) composite coatings with varying-content MWCNTs (0, 0.1, 0.2, 0.5 and 0.9 g/L) on the surface of AISI 1045 steel were produced by electro-brush plating technique. The effect of MWCNTs concentration in the plating solution on the microstructures and of the composite coatings was discussed in detail. The co-deposition of MWCNTs with Fe atom occurs in the Fe-based coating, which can decrease the number of through-wall cracks and increase the deposition velocity whereas the phase structure of the composite coatings cannot be affected. When the content of MWCNTs added in the plating solution is 0.2 g/L, the microhardness (612 HV0.3) of coating is much higher than that of pure Fe coating (489 HV0.3). The friction coefficient and weight loss of all Fe/MWCNTs composite coatings are significantly lower than that of pure Fe coating, which is attributed to the effect of reinforcement and lubrication of MWCNTs.