Effect of plasma nitriding at low temperature on the corrosion resistance and conductivity of 2205 duplex stainless steel

Abstract

A nitrogen expanded austenite (γ N ) layer with a thickness of 3 μm was prepared by plasma nitriding of 2205 duplex stainless steel (DSS) at 460°C for 1 h with hollow cathode discharge assistance. The microstructure and phase composition of nitrided specimens were examined. The electrical conductivity of nitrided samples was measured before and after the corrosion test, respectively. The corrosion current density of nitrided 2205 DSS polarized for 4 h was 1.3 μA cm −2 (at 0.6 V) and −1.4 μA cm −2 (at −0.1 V), respectively. The interfacial contact resistance (ICR) of the nitrided 2205 was 14.7 mΩ cm 2 which was much lower than that of bare 2205 DSS substrate (93.6 mΩ cm 2 ) after 4 h potentiostatic polarization at cathodic conditions. The corrosion resistance and electrical conductivity were evidently improved compared with 2205 DSS substrate.

Formation of Polyacetylene Films on Copper Substrate by Abnormal Glow Discharge

“…It is reported in the literature that an increase in the corrosion potential and a decrease in the corrosion current, with respect to the untreated sample, are parameters that indicate that a material has improved its corrosion resistance [19], [20], [21]. As shown in Table 1, two coatings meet both premises, the 5 s and the 120s.…”

Corrosion resistance of NbN and NbxAlyN coatings on stainless steel

“…An equal 3-electrode cell apparatus and stabilization period was employed in the potentiodynamic polarization tests. Starting from −30 mV below the OCP, the potential was swept at a scanning rate of 1 mV s −1 [16][17][18][19]. Potentiodynamic tests were performed in triplicates.…”

Investigation of evolution of γ N phase and its effect on conductivity and corrosion resistance of plasma-nitrided 316 L stainless steel bipolar plate for proton exchange membrane fuel cell

“…Nitriding treatment is driven by the concentration gradient, nitrogen atoms gradually are diffused into the material to achieve the purpose of nitriding, and there is no interface adhesion problem between the nitriding layer and the matrix. The plasma nitriding technology is the best way to improve the surface properties of the stainless steel because it has the advantages of mass production, no pollution and low cost [13,14]. The previous research results indicated that the plasma nitriding treatment can significantly enhance the conductivity and corrosion resistance of metals [15][16][17][18].…”