Cu、Mn的协同作用对低合金钢在模拟海洋大气环境中腐蚀的影响

    用增重法、扫描电镜、X射线衍射、电子探针和X射线光电子能谱等手段研究了在模拟海洋大气干湿交替环境下16Mn钢和Cu-Mn耐候钢的腐蚀行为及Cu、Mn共添加对低合金钢腐蚀行为的影响.结果表明：Cu-Mn耐候钢的腐蚀速率低于16Mn钢，其锈层更致密；两种钢的铁锈均由Fe₃O₄，α-FeOOH，β-FeOOH，γ-FeOOH和大量无定形相组成；添加Cu使Fe₃O₄含量增加，添加Mn使γ-FeOOH含量减少；Cu在Cu-Mn耐候钢锈层中以CuFeO₂存在；Mn在两种钢锈蚀初期以MnO存在，后期为Mn₃O₄.Cu、Mn的协同作用使Cu-Mn耐候钢抗大气腐蚀性能优于16Mn钢.

INFLUENCE OF Cu AND Mn ON CORROSION BEHAVIOR OF LOW ALLOY STEEL IN A SIMULATED COASTAL ENVIRONMENT

    Corrosion rates of 16Mn steel and Cu-Mn weathering steel in a simulated coastal environment are measured by wet/dry cyclic test.The rust layer was observed and analyzed by SEM,XRD and XPS.The experimental results show that the corrosion rate of Cu-Mn weathering steel was lower than that of 16Mn steel,due to the formation of a denser rust layer.The  rusts on the two steels were consisded of Fe₃O₄，α-FeOOH，β-FeOOH，γ-FeOOH and amorphous. The amount of α-FeOOH and β-FeOOH in the rust of 16Mn was larger than in that of Cu-Mn steel.The addition of Cu increased the amount of Fe₃O₄，while the addition of Mn decreased the amount of γ-FeOOH in the rusts.XPS results show that,Cu existed in the form of CuFeO₂;Mn existed as MnO in the initial stage,and then transferred to Mn₃O₄ after the rust layer stabilized.The synergetic effect of Cu and Mn improved the corrosion resistance of Cu-Mn steel.