铜合金在海水中的腐蚀行为研究

Corrosion Behavior of Copper Alloy in Seawater

通过高速旋转腐蚀试验、X射线衍射、扫描电镜(SEM)及能谱分析(EDAX)、电化学特征测定等对Cu-2.9Sn-0.9Al铜合金在人工海水中的腐蚀行为进行了研究。结果表明,添加2.9％Sn、0.9％Al的铜合金在室温、pH值为8.2的人工海水中具有较好的耐腐蚀性。其高耐蚀性主要是由于在合金表面形成一层氧化膜,它对阳极过程和阴过程都有影响。这层膜是Cu的氧化物和Sn的氧化物及Cu-Al-Mg共析化合物的复合保护膜。它们的协同作用降低了氧化层的孔隙度,从而避免了局部酸性区域的形成而导致的局部腐蚀。

Corrosion behavior of Cu-2. 9Sn-0. 9A1 alloy in seawater was studied by high speed rotating corrosion test, XRD, SEM, EDAX, and electrochemical method. Results showed the copper alloy with 2.9%Sn and 0.9%Al had excellent corrosion resistance in artificial seawater of pH = 8.2 at ambient temperature. The high corrosion resistance was due to ibrming an oxidation film on the surface of alloy, which might affect both the anodic and cathodic pro-cess. The film was consisted of copper oxide and tin oxide and Cu-Al-Mg complex compound, whose synergetic effect made the porosity of oxide coating decreasing, thus avoided the local corrosion resulted by formation of local acidic area.