通过电化学测式技术和化学浸泡方法 ,在高温 55%LiBr +0 .0 7mol/LLiOH溶液中研究了MoO4 2 - 对低合金钢的电化学行为作用 .结果表明 ,MoO4 2 - 作为阳极型缓蚀剂能促进钝化 ,阻滞了阳极和阴极反应 .Na2 MoO4 浓度达到 2 0 0mg/L时 ,可有效地抑制低合金钢的活性溶解 .低合金钢中添加Cr和Ni元素可改善耐蚀性能 ,而AI元素则使耐蚀性能变劣 .Mo元素参与成膜过程 ,Cr和Mo元素的协调作用 ,使A钢能在较低Na2 MoO4 浓度下进入钝态
By electrochemical measurements and weight loss experiments, the effect of MoO 4 2- on low alloy steel's electrochemical behaviors was investigated at high temperature in 55%LiBr+0.07 mol/L LiOH solution. The results showed that MoO 4 2- ,as an anodic inhibitor, formed passive film rapidly and impeded both anodic and cathodic procedures. Moreover, Na 2MoO 4 prevented corrosion effectively in 55%LiBr+0.07 mol/L LiOH solution when its concentration is more than 200 mg/L. The pitting potential increased accompanying to the arising of Na 2MoO 4 concentration.Some elements of alloy strengthened resistance to corrosion, shch as chromium and nickel, but aluminum promoted corrosion. Molybdenum participated in forming protecion film. The harmonizing effect between chromium and molybdenum induced steel A to be in passive state in lower Na 2MoO 4 concentration.
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