Characterization of electrodeposited nanocrystalline cobalt-iron coating with different iron content

Abstract

The nanocrystalline cobalt-iron (CoFe) alloy coatings were produced using the electrodeposition technique. Effect of different iron concentrations on the surface morphology, surface roughness, grain size, crystalline texture and wear resistance of the deposited CoFe were investigated. Nanocrystalline CoFe alloy coatings were electrodeposited in a sulfate bath with varying iron sulfate concentration. The temperature and pH were maintained at 40 °C and 3, respectively. The results show that grain size decreased with an increase of iron content in the deposited CoFe alloy coatings. The preferred orientation plane for the alloy coating exhibited an FCC and BCC phase depending on the iron content present in the coating. The microhardness of the nanocrystalline CoFe alloy coating were also seen to increase with higher iron content in the deposited coating. Furthermore, the surface roughness was seen to increase with higher iron concentration of the deposited alloy coating. Interestingly, higher wear resistance was obtained from coatings produced with the lowest iron concentration. This work shows that deposited CoFe alloy coating with low iron content could act as a protective layer to increase the lifetime of components exposed to wear environments.