高铝、铁青铜Cu-15Al-xFe在NaCl溶液中的腐蚀行为

Corrosion Behavior of High Al- and Fe-Bronze Cu-15Al-xFe in NaCl Solution

通过电化学极化、静态浸泡等方法研究了真空吸铸态高铝、高铁青铜合金Cu-15Al-x Fe(x=10,12,15,质量分数)在3.5%(质量分数)Na Cl溶液中的腐蚀行为,用扫描电镜及能谱仪对亚快速凝固合金腐蚀前后微观组织和腐蚀形貌进行了观察,分析了铝青铜合金的腐蚀机理及Fe含量对铝青铜合金耐蚀性的影响。结果表明:在3.5%Na Cl溶液中,Cu-15Al-x Fe合金中的富铁相与基体相比,具有明显的优先腐蚀倾向,合金主要发生脱Al和Fe选择性腐蚀,这主要是由于富铁相组织中Al和Fe含量高于基体组织所致。其中,Fe含量为12%时合金的耐蚀性最好。

Sub-rapidly solidified Cu-15Al-x Fe（x=10, 12, 15） alloy bars were prepared by copper mould casting. The corrosion behavior of the bronzes in 3.5% Na Cl solution was investigated by means of potential dynamic polarization measurement and static immersing corrosion test. The microstructure of the bronzes before and after corrosion test was characterized with scanning electron microscope（SEM） and energy dispersive spectrometer（EDS）, and then the relevant corrosion mechanism and the effect of Fe content on the corrosion resistance were discussed in detail. The results showed that the corrosion resistance of Cu-15Al-12 Fe alloy is the best in 3.5%Na Cl solution.The three bronzes Cu-15Al-x Fe（x=10, 12, 15） all suffered from selective corrosion, which was resulted from the dealuminization and deferrization of the phase reach in Fe and Al.