稀土元素Ce对204Cu奥氏体不锈钢耐腐蚀性能的影响

204Cu奥氏体不锈钢(/%:0.125~0.131C，0.32~0.34Si，8.51~8.73Mn，0.002~0.006S，0.035~0.007P，16.40~16.64Cr，2.53~2.72Ni，2.33~2.38Cu，0.257~0.271N，0~0.064Ce)由10 kg真空感应炉熔炼,锻成25 mm×25 mm方坯,并进行1150℃ 2 h水冷的固溶处理。利用重量法和电化学法的交流阻抗和极化曲线技术研究了0~0.064%Ce对204Cu不锈钢在25℃ 3.5%NaCl溶液中耐腐蚀性能的影响。结果表明,204Cu不锈钢中加入一定量的稀土元素Ce,204Cu不锈钢的阳极极化电位值正移,降低腐蚀电流密度,增加极化电阻,可以显著提高其耐腐蚀性能,当向钢中加入0.029%Ce时,204Cu不锈钢可以获得最佳的耐腐蚀性能。

Effect of Rare Earth Element Ce on Corrosion-Resisting Properties of Austenite Stainless Steel 204Cu

The austenite stainless steel 204Cu (/% : 0.125-0.131C, 0.32-0.34Si, 8.51-8.73Mn, 0.002-0.006S, 0.035-0.047P, 16.40-16.64Cr, 2.53-2.72Ni, 2.33-2.38Cu, 0.257-0.271N, 0-0.064Ce) is melted by a 10 kg vacuum induction furnace, forged to 25 mm x 25 mm square billet, and solid-solution-treated at 1150 ℃ for 2 h, water cooling. The effect of 0-0.064% Ce on corrosion-resisting properties of stainless steel 204Cu in 3.5% NaCl solution at 25 ℃ has been studied by using weight method, electrochemical polarization curves and AC impedance techniques. Results show that adding definite earth element Ce in stainless steel 204Cu, the anod polarization voltage value shifts positively ,the corrosion current density decreases and the polarization resistance increases , that can obviously increase its corrosion-resisting properties, as adding 0.029% Ce the stainless steel 204Cu has optimizing corrosion-resisting properties.