高氮钢在含Na_2S饱和CO_2溶液中的腐蚀电化学行为

Electrochemical Corrosion Properties of HNS in Saturated CO_2 Solution Containing Na_2S

通过电化学测试方法,对高氮钢在含Na_2S饱和CO_2溶液中的腐蚀电化学行为进行研究,得到高氮钢的钝化稳定性和腐蚀规律。在含Na_2S的饱和CO_2腐蚀介质中,Cr13的钝化膜表面载流子密度最大,钝化稳定性最差,耐蚀性最差,316L钢较好,高氮钢最优。随着Na_2S浓度的增大,高氮钢的点蚀电位下降,钝化区间变窄,维钝电流变大,钝化膜层的电荷传递电阻降低,高氮钢钝化稳定性能变差,耐蚀性变差。随着温度的升高,高氮钢的自腐蚀电位和点蚀电位均下降,维钝电流增大,钝化膜表面的载流子浓度也增大,且其电荷传递电阻和膜层电阻也降低,钝化稳定性下降。

Having the electrochemical testing method adopted to investigate electrochemical corrosion properties of HNS（high nitrogen steel） in Na2S-contained saturated CO2 solution was implemented to obtain HNS＇s passivation stability and corrosion rules. The test results show that, in Na2S-contained saturated CO2 corrosive solution, the surface carrier of Crl3 stainless steel＇ s passivation film has maximal density and it has the worst passivation stability and corrosion resistance; and in the same corrosion environment, the HNS outperforms 316L steel in the corrosion resistance; with the increasing of Na2S concentration, the pitting potential of HNS becomes decreased and the passive current density increased; the passive film＇ s resistance of charge transfer becomes decreased and the HNS＇ passivation stability and corrosion resistance decreased; with the rise of the temperature, the HNS＇ corrosion potential and pitting potential get decreased and both passivation current and surface carrier＇ s concentration increased and its charge transfer resistance and passive film resistance become decreased along with a decreased passivation stability.