奥氏体不锈钢在含铀碳酸钠溶液中的腐蚀行为

Corrosion Behaviors of Austenite Stainless Steel in Sodium Carbonate Solution Containing Uranium

用动电位极化法和均匀腐蚀法研究了奥氏体不锈钢 (1Cr18Ni9Ti)在含铀碳酸钠溶液中的腐蚀行为。结果表明 :铀酰离子对碳酸钠溶液中奥氏体不锈钢电极的阳极反应有抑制作用 ,95℃温度下 ,经过 2 0 0 0h ,奥氏体不锈钢在 0 .0 6mol/LNa4UO2 (CO3 ) 3 +1.1mol/LNa2 CO3 混合溶液中未发生可观测的腐蚀。给出了奥氏体不锈钢电极在含铀碳酸钠溶液中的腐蚀电位、腐蚀电流密度。腐蚀样品经XRD分析表明沉积物由UO3 和Na4UO2 (CO3 ) 3 组成 ,XPS分析表明其中铀的氧化态为铀 (Ⅵ )。初步探讨了碳酸铀酰离子的作用机制 。

Corrosion behaviors of austenite stainless steel 1Cr18Ni9Ti in sodium carbonate containing uranium were studied by electrochemical polarization and general corrosion methods.Results show that uranyl ion has inhibition for the anodic process of stainless steel in sodium carbonate.Unobservable corrosion occurs on the stainless steel electrode after 2 000 hours immersion at 95℃ in the solution.The corrosion potential and corrosion current density of stainless steel in the solution are presented.XRD analysis proves that the corrosion product is composed of UO_3 and Na_4UO_2(CO_3)_3,and XPS analysis indicates that the oxidation state of uranium is U(VI)valence.The inhibition mechanism of uranyl ion was investigated,and the corrosion resistance of austenite stainless steel was discussed.