Electrochemical behavior of steel-FeNbC composites used in the production of oxygen

Abstract

The electrocatalytic properties of steel-FeNbC composites were evaluated after potentiostatic ageing with the purpose of establishing the potential use of such materials as electrodes for the industrial production of oxygen. The effect of processing parameters, involved in the production of the composites by powder metallurgy, such as milling conditions and compaction pressure, on the performance of the electrodes was also studied. The electrodes were characterized according to their electrical resistance in NaOH 1M solution, considering that the purpose of the application requires this value to be ~ 0.5 .cm 2 . This parameter was evaluated from repetitive electrochemical measurements carried out from 0.7 V to 1.5 V (vs. Ag/AgCl) by electrode anodization. Changes in the electrochemical behavior of the electrodes, especially concerning the O 2 evolution in alkaline medium, were studied as a function of the applied potential. The results revealed that the electrocatalytic activity of the electrodes increased upon ageing, probably as a consequence of the growth of oxide layers and/or increase in the conductivity of the material, resulting in current gain and corresponding decrease in the polarization resistance to 0.75 cm 2 .

Effect of flame spray deposition parameters on the microstructure, microhardness and corrosion resistance of FeNbC coatings on AISI 1020 steel

“…The results obtained in the polarization tests indicate that the FeNbC coating in most cases improved electrochemical behavior compared to the uncoated sample, however this performance of corrosion resistance could be differentiated. It is suggested that this behavior may be affected by low compaction and the presence of porosity and other defects such as voids and cracks in the coating, this condition was also related by other authors [45].…”

Sintering Techniques of Materials

“…Particularly, reinforced steel has been used in the automotive and textile industries and also in the manufacture of high-speed cutting and ore milling tools (Martinelli, et al, 2007). Advances in research (Silva, 2005;Silva, et al, 2005; and Silva, et al, 2012) and marketing of steel reinforced with NbC and TaC particles have also contributed to add value to manufactured products strategically using mineral sources produced in northeastern Brazil.…”

Metal Matrix Composites Added of Nanostructured Tantalum Carbide

“…Particularly, reinforced steel has been used in the automotive and textile industries and also in the manufacture of high-speed cutting and ore milling tools (Martinelli, et al, 2007). Advances in research (Silva, 2005;Silva, et al, 2005;and Silva, et al, 2012) and marketing of steel reinforced with NbC and TaC particles have also contributed to add value to manufactured products strategically using mineral sources produced in northeastern Brazil.…”