from the conferences organized by TANGER Ltd.
The martensitic stainless steel AISI 410 was subjected to plasma nitriding at an increased temperature of 550 °C, 24 h in 3H2:1N2 (l/h) nitriding gas ratio and compared to untreated one. The microstructure and microhardness of the untreated and nitrided stainless steel were evaluated. The corrosion properties of the untreated and plasma nitrided steel samples were evaluated using the anodic potentiodynamic polarization tests in neutral 2.5% NaCl deaerated solution. The phase analysis of nitrided steel sample was compared to untreated one. The results showed that plasma nitriding process on the X12Cr13 Steel (AISI 410) stainless steel produced a nitride layer consisting of compound layer and a nitrogen rich diffusion layer with iron carbides Fe3C, iron nitrides Fe4N, chromium nitrides Cr4N4 and chromium iron carbide Cr15Fe7C6. Plasma nitriding process significantly increased the surface hardness of the martensitic stainless steel but also decreased the corrosion resistance. The pitting and type of corrosion were evaluated, and the pitting coefficient was calculated. During electrochemical corrosion tests, the nitrided AISI 410 stainless steel showed lower corrosion potentials (more negative), higher current densities (nearly forty times higher) and nearly forty times increased corrosion rates compared to untreated X12Cr13 stainless steel.
Keywords: Plasma nitriding, stainless steel, corrosion resistance© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.