铝合金的中性盐雾腐蚀行为

Research on the Neutral Salt Spray Corrosion Behavior of Aluminum Alloys

为了更好地建立铝合金耐蚀性能评价体系,采用中性盐雾试验对纯铝及4类铝合金的耐蚀性进行了考察,观察了不同腐蚀时间下各试样的宏观腐蚀形貌,并结合扫描电镜(SEM)及能量色谱仪(EDS)对5类试样的微观腐蚀形貌、腐蚀产物的元素分布进行了分析研究,比较了5类试样不同试验时间下的平均腐蚀失重。结果表明:试样表面变色是铝合金开始腐蚀的一个特征,疏松白色腐蚀物及凝胶状腐蚀物是铝合金局部腐蚀严重的体现,铜元素的加入极大地影响了铝合金的耐蚀性。

In order to establish the corrosion resistance evaluation system of aluminum alloy better,the corrosion resistance of pure aluminium and four aluminium alloys was evaluated by salt spray test(NSS),and the macroscopic corrosion morphology of the five types of samples under different corrosion time was observed.In addition,the micro-corrosion morphology and element distribution of corrosion products of the five types of samples were analysed by scanning electron microscopy(SEM)and energy dispersion spectrometer(EDS).The average corrosion weight loss of five types of samples under different test time was compared.Results showed that the discoloration of the sample surface was a characteristic of the beginning corrosion of aluminium alloys,the loose white and gelatinous corrosion products were the reflection of the serious local corrosion of aluminium alloys,and the addition of copper greatly affected the corrosion resistance of aluminium alloys.