The RE Catalysis Effect On Corrosion Resistance Gas Nitriding Of Low Carbon Steel

Production of RE elements on corrosion resistance Nitriding and organization structure ingredient mechanical property and corrosion resistance on the nitriding case was studied by Orthogonal Testing design , advantage, regulation of nitriding layers effected by nitriding production ,compared RE-nitriding layers with conventional nitriding layers ; production of composite Corrosion Resistance Nitriding of Low Carbon Steel was tentative studied.The experimental results obtained have shown that: velocity of Nitriding was obviously increased , with addition of RE during Nitriding. Bonding force of nitriding layers and matrix was greatly improved comparing with conventional nitriding layers, corrosion resistance was increased ,the time of corrosion in salt spray corrosion up to 242 hours, microhardness of nitriding layers remarkable improved . corrosion potential of RE-nitriding layers decrease with increase of temperature and [CP] ; this exhibits corrosion resistance of RE-nitriding layers decrease with increase of temperature and [Cl~-] ; corrosion potential of RE-nitriding layers remove to cathode in the acidity NaCl solution comparing with neutrality and alkaline solution. This showed corrosion resistance of RE-nitriding layers was preferable in the neutrality and alkaline environment ; EIS displays that RE-nitriding layers remove with time in the NaCl solution, corrosion was controlled by electrochemistry process and then by diffusion process, and firstly the speed relief then acceleration, which according with Tafel curve. The best RE-nitriding processes of Q235 is 600℃×2.5h decomposition rate of Ammonia: 50 % the extent of RE: 30d/min . The result of Q235 of RE-nitriding showed composite nitriding was propitious to increase corrosion resistance.