Polarization Characteristics of Heat-treated Ni-based Self-flux Alloy Coating in Alkaline Solution

Abstract

The purpose of this paper is to investigate polarization characteristics of heat-treated Ni-based self-flux alloy coating in alkaline solution. Ni-based self-flux alloy powder was sprayed to a steel substrate using flame spray process, and heat treatments were performed in a vacuum furnace at 800℃, 900℃, 1000℃ and 1100℃. After heat treatments, corrosion tests were carried out using potentiostat/galvanostat at solution with pH 8 and pH 13. Corrosion potential(Ecorr) and corrosion current density(Icorr) could be analyzed from polarization curve. Anticorrosive effect of heat-treated coating at solution with pH 8 was relatively greater than at solution with pH 13. Heat-treated coating at 1100℃ showed the greatest anti-corrosion characteristics in alkaline solution.