铜铝层状复合板中性盐雾腐蚀行为研究

采取模拟大气环境的室内中性盐雾腐蚀实验,探讨了铜铝层状复合材料的腐蚀行为。通过扫描电镜(SEM)观察腐蚀后铜铝界面形貌,结合X射线衍射仪(XRD)和能谱仪(EDS)分析腐蚀产物成分,并通过电化学检测分析试样经过不同时间盐雾腐蚀后的表面腐蚀状态,探讨铜铝复合板在服役环境下的腐蚀机制。结果表明:铜铝复合板在盐雾环境下铜铝构成腐蚀原电池,Al为阳极铜为阴极,阴阳极面积比越大,腐蚀速率越大。随着腐蚀的不断进行,铜铝界面的Cu一侧发生腐蚀,且靠近界面的位置腐蚀最为严重,随着腐蚀时间延长,铝基体出现严重的剥蚀现象,Cu几乎无变化。腐蚀产物成分为Al2O3,Al(OH)3和AlO(OH),电化学结果显示:铜铝复合板在腐蚀的过程中,腐蚀速率呈现先增加后减小再增加的趋势。

Corrosion Behavior of Cu-Al Laminated Board in Neutral Salt Fog Environment

The corrosion behavior of Cu-Al laminated boards was investigated by means of indoor neutral salt spray test, aiming to simulate the atmospheric environment induced corrosion, and electrochemical workstation, as well as scanning electron microscopy(SEM) with energy spectrometer(EDS),and X-ray diffractometer(XRD). The results show that Cu-and Al-laminates act as corrosion galvanic couple in salt spray environment, where the Cu plays as cathode, while Al as anode. The greater the area ratio of cathode to anode, the greater the corrosion rate. As the corrosion continued, the corrosion mainly occurred on the Al plate, and the corrosion was the most serious near the interface of the Cu-Al plates,serious denudation corrosion may appear on the Al-plate for long-term corrosion, while the Cu plate has almost no change. The corrosion products composed mainly of Al2O3, Al(OH)3 and AlO(OH). The electrochemical results show that during the corrosion process, the corrosion rate of Cu-Al composite laminated board increased firstly, then decreased and finally increased again.