有机膦酸盐对碳钢在NaHCO3—Na2CO3溶液中钝化性能的影响

采用恒电位方法研究了羟基乙叉二膦酸（ＨＥＤＰ）、二乙烯三胺五甲太膦酸（ＤＥＴＰＭＰ）、三乙烯四胺六甲叉膦酸（ＴＥＴＨＭＰ）、乙二胺四叉膦酸（ＥＤＴＭＰ）对碳钢在ＮａＨＣＯ３－Ｎａ２ＣＯ３缓冲液中钝化过程破裂电位的影响，结果表明；在一定的浓度范围内，上述有机膦酸盐能促进碳钢的钝化，并能使其进入自钝化状态，但当有机磷酸盐浓度增中到一定值后，碳钢的阳极溶解电流又重新增大，有机磷酸盐对碳钢在在含Ｃｌ离子的

Influence of Organic Phosphonate on the Passivation of Mild Steel in NaHCO 3 Na 2CO 3 Solution

The influence of hydroxyl ethylene diphosphonic acid (HEDP),diethylenetriamine pentmetylene phosphonic acid (DETPMP),triethyleneteramine heramethyl phosphonic acid (TETHMP) and ethylene diamine tetramethylene phosphonic acid(EDTMP) on passivation behavior,and the potential of breakdown of passivity of mild steel in NaHCO 3 Na 2CO 3 buffer solution were investigated by potentiostatic polarisation.The results can be obtained as follows:These organic phosphonate can accelerate the passivation of mild steel and make to be passivity by itself in fit concentration range;the anodic current of mild steel increases again as the concentration of the organic phosphonate increases to a certain value;and these organic phosphonates have no inhibiting ability to pitting of mild steel in the presence of Cl ion of NaHCO 3 Na 2CO 3 solution.