A new process of flat absorber black nickel alloy coating tion from a bath containing nickel, zinc and ammonium was developed on stainless steel by electrodeposi- sulphates; thiocyanate and sodium hypophosphite for sp...A new process of flat absorber black nickel alloy coating tion from a bath containing nickel, zinc and ammonium was developed on stainless steel by electrodeposi- sulphates; thiocyanate and sodium hypophosphite for space applications. Coating process was optimized by investigating the effects of plating parameters, viz concentration of bath constituents, current density, temperature, pH and plating time on the optical properties of the black deposits. Energy dispersive X-ray spectroscopy showed the inclusion of about 6% phosphorous in the coating. The scanning electron microscopy studies revealed the amorphous nature of the coating. The corrosion resistance of the coatings was evaluated by the electrochemical impedance spectroscopy （EIS） and linear polarization （LP） techniques. The results revealed that, phosphorous addition confers better corro- sion resistance in comparison to conventional black nickel coatings. The black nickel coating obtained from hypophosphite bath provides high solar absorptance （αs） and infrared emittance （εIR） of the order of 0.93. Environmental stability to space applications was established by the humidity and thermal cycling tests.展开更多
文摘A new process of flat absorber black nickel alloy coating tion from a bath containing nickel, zinc and ammonium was developed on stainless steel by electrodeposi- sulphates; thiocyanate and sodium hypophosphite for space applications. Coating process was optimized by investigating the effects of plating parameters, viz concentration of bath constituents, current density, temperature, pH and plating time on the optical properties of the black deposits. Energy dispersive X-ray spectroscopy showed the inclusion of about 6% phosphorous in the coating. The scanning electron microscopy studies revealed the amorphous nature of the coating. The corrosion resistance of the coatings was evaluated by the electrochemical impedance spectroscopy （EIS） and linear polarization （LP） techniques. The results revealed that, phosphorous addition confers better corro- sion resistance in comparison to conventional black nickel coatings. The black nickel coating obtained from hypophosphite bath provides high solar absorptance （αs） and infrared emittance （εIR） of the order of 0.93. Environmental stability to space applications was established by the humidity and thermal cycling tests.
