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The mechanical properties like hardness, tensile strength, wear resistance of electro-co-deposited Ni-SiC coatings are dependent on factors like bath temperature, current density, duration of deposition, amount of SiC particles etc. Ni-SiC nano composite coatings were prepared on a mild steel substrate by electro-co-deposition process. In this study, the effect of electrochemical bath parameters such as bath temperature, current density and SiC loading were varied and effect of this variation on the coating thickness and tensile strength of Ni-SiC composite coating was studied. The experimental results showed that, a uniform deposit thickness was obtained for 3 A/dm² current density, temperature of 55°C and loading of 4 g/l. A peak value of coating thickness was observed at a current density of 4 A/dm² from the experiment. The experimental results also showed that, the tensile strength of the composite coating containing SiC the is significantly higher than pure Ni coating and the tensile strength increases with an increase in the percentage of SiC particles in Ni-SiC coatings. The tensile strength of the composite coating increased by nearly about 52% with increasing SiC loading and then decreased.

This paper aims to examine the investigations made on the corrosion behaviour of magnesium (Mg) substrate electrodeposited using different nano-materials.

This study uses nano-materials such as those of reduced graphene oxide (r-GO), titanium-di-oxide (TiO₂) and also r-GO/TiO₂ nano-composites (dispersed through ultra-sonication process) at 3-min time interval. Crystalline nature of synthesized TiO₂ is studied through X-ray diffraction and its pore volume is measured to be approximately 0.1851ccg-1 by Brunauer Emmett Teller analysis.

Surface morphology of the developed set of specimens inspected through scanning electron microscopy and energy dispersive spectroscopy establishes a clean surface coating and further witnesses for only minimal defects. Electrochemical behaviour of the developed coating is studied exhaustively using Tafel polarization and electrochemical impedance spectroscopy in 0.1 M Na₂SO₄ solution.

Incremental corrosion resistance exhibited by developed composite coating owes to the factors viz. chemical stability and hydrophobic tendency of TiO₂ and r-GO; these known engineering facts resist the flow of ions into the corrosive media and thereby reduce the rate of corrosion.

The purpose of this paper is to investigate the interfacial conductivity and corrosion resistance of the Ni–P/Ti₄O₇ composite coating that is deposited on a carbon steel substrate as bipolar plates for proton exchange membrane fuel cells.

The Ni–P/Ti₄O₇ coating was prepared by electroless plating. Scanning electron microscopy, white light interference, energy dispersive spectrometry and X-ray diffraction were used, respectively, to study the surface morphology, chemical composition and phase composition of coated samples. Electrochemical impedance spectroscopy, potentiodynamic and potentiostatic polarization were used to test the electrochemical performance and corrosion behavior. The interfacial contact resistance (ICR) was measured via the standard method.

The surface of the Ni–P/Ti₄O₇ coating is complete and dense and without obvious defects. The electrochemical test results show that the Ni–P/Ti₄O₇ coating provides better corrosion resistance than the Ni–P coating and substrate. Compared with the Ni–P coating, the ICR of the Ni–P/Ti₄O₇ coating is lower by about 82.7%. This is because the coating has more conductive contact points. The more exciting thing is that the ICR of the Ni–P/Ti₄O₇ coating only increases to 12.38 mΩ·cm² after 5 h of polarization.

This paper provides a method for achieving surface modification of metal bipolar plates. Introducing Ti₄O₇ particles in the Ni–P layer reduces the contact resistance before and after polarization while ensuring good corrosion resistance.