在NaHCO_3-NaCl体系中阴离子对低碳钢点蚀的抑制作用  

EFFECT OF ANIONS ON PITTING CORROSION OF A3 STEEL IN NaHCO_3-NaCl SOLUTION

作　　者：赵景茂[1] 左禹[1] 熊金平[1] 田连朋[1] 

机构地区：[1]北京化工大学材料科学与工程学院北京100029

出　　处：《腐蚀科学与防护技术》2001年第2期77-80,共4页Corrosion Science and Protection Technology

基　　金：国家重点基础研究规划! (G19990 65 0 );北京市自然科学基金!(2 972 0 0 9)

摘　　要：采用动电位和恒电位技术研究了低碳钢在NaHCO3 -NaCl体系中的点蚀电位和再钝化电位的分布以及 5种阴离子对它们的影响 .结果表明 ,点蚀电位和再钝化电位均服从正态分布 ;在 5种阴离子中 ,NO-2 和MoO2 -4 能够抑制点蚀的发生和发展 ,而SO2 -4 、NO-3 在低浓度时降低点蚀电位和再钝化电位 ,促进点蚀的发生 ,在高浓度时能够破坏自钝化 ;Cr2 O2 -7能显著抑制点蚀的发生 。The effects of anions on the pit nucleation and growth on A3 steel in NaHCO 3-NaCl solutions were investigated by potentiodynamic and potentiostatic techniques. Pitting potential and repassivation potential were shifted towards positive direction by the addition of NO - 2 and MoO 2- 4, indicating suppression of pit nucleation and propagation. Cr 2O 2- 7 anion suppressed pit nucleation but stimulated pit growth. SO 2- 4, NO - 3 anions stimulated both pit nucleation and propagation at low concentrations.The pitting potential and repassivation potential decreased linearly with logarithm of SO 2- 4 concentration. Increasing the concentrations of SO 2- 4, NO - 3 over 0.02M changed the potential from passive to active region. Pitting potential and repassivation potential of carbon steel were found to obey normal distributions.

关 键 词：阴离子 点蚀 低碳钢 NaHCO3-NaCl水溶液 

分 类 号：TG172.63[金属学及工艺—金属表面处理] TG174.41[金属学及工艺—金属学]