中文摘要：

目的 研究2205双相不锈钢在一级反渗透（RO）淡化海水、海水及浓缩海水中的点蚀行为。方法 运用开路电位、交流阻抗、阳极极化曲线和电化学频率调制技术研究2205双相不锈钢在不同温度（60-90℃）及不同海水（一级反渗透淡化海水、天然海水、1.6倍浓缩海水）中的点蚀行为。结果 2205双相不锈钢在一级RO淡化海水中,随温度升高,自腐蚀电位逐渐负移。在80℃的一级RO淡化海水中,在浸泡1 d时即有发生点蚀的倾向,在第28 d时已经发生了稳态蚀点。浸泡初期不锈钢的扰动电流为2μA/cm-2之内,浸泡41 d的扰动电流接近12μA/cm^2,且其值波动幅度更大。结论 随着温度的升高钝化膜稳定性降低,2205不锈钢耐蚀性降低。钝化状态下,其在一级RO淡化海水中比在海水中腐蚀严重,点蚀敏感性随Cl^–浓度的升高而增加。

英文摘要：

Objective To study pitting corrosion behaviors of 2205 duplex stainless steel in level 1 reverse osmosis desalination seawater, natural seawater and concentrated seawater. Methods Open circuit potential, alternating-current impedance, anode polarization curve and electrochemical frequency modulation （EFM） were used to study pitting corrosion behaviors of 2205 duplex stainless steel in different water （level 1 reverse osmosis desalination seawater, natural seawater and 1.6 times concentrated seawater） at different temperature （60-90 ℃）. Results The EocP of 2205 duplex stainless steel changed to negative with the temperaftre increasing in level 1 reverse osmosis desalination seawater. In level 1 reverse osmosis desalination seawater at 80 ℃, the trend of pitting corrosion was found in the 1st day, and stable pitting occurred in the 28th day. The turbulent current of stainless steel was within 2 μA/cm^2 at the beginning, it was near 12 μA/cm^2 in the 41th day and the fluctuation amplitude was bigger. Conclusion The stability of passive film and the anti-corrosion of 2205 duplex stainless steel decrease with temperature increasing. In passive state, the corrosion ability is more severe in level 1 reverse osmosis desalination seawater than in artificial seawater. The sensibility to pitting corrosion increases with the increase of CF concentration.