CO_2饱和高温弱酸性介质中Ni-Cu-P合金、纯Ni和A3钢的电化学行为

Electrochemical Behaviors of Ni, A3 Steel and Ni Cu P Alloy in CO 2 Saturated Weak Acid at High Temperature

用线性极化法、极化曲线法和失重法研究了化学镀Ｎｉ－Ｃｕ－Ｐ非晶态合金、纯Ｎｉ和Ａ３钢于１４０℃、ｐＨ值５．０、ＣＯ２饱和的２％（ｗｔ）Ｎａ２ＳＯ４溶液中的腐蚀电化学行为。结果表明，在该介质条件下，Ｎｉ－Ｃｕ－Ｐ合金、纯Ｎｉ和Ａ３钢的耐蚀性依次减弱，比值为８１．２∶２３．９∶１．０。Ｎｉ－Ｃｕ－Ｐ合金于２５０～５５０ｍＶ（ｖｓＯＰ）区间发生钝化；纯Ｎｉ在５０～１５０ｍＶ和高于４００ｍＶ（ｖｓＯＰ）的电位下发生两次钝化；而Ａ３钢在高于４００ｍＶ（ｖｓＯＰ）的电位下呈现浓差极化。３种材料于介质中的腐蚀速率随温度的升高而增大。

AbstractThe electrochemical behaviors of Ni, A3 steel and Ni Cu P alloy in CO 2 saturated weak acid (pH=5) at 140 ℃ were studied by polarization curve and weight loss methods. The ratio in corrosion resistance of Ni Cu P alloy ,pure Ni and A3 steel was 81.2∶ 23.9∶1.0.