铝粉的质量分数对达克罗涂层耐蚀性的影响

Influence of the Mass Fraction of Aluminum Powder on the Corrosion Resistance of Dacromet Coating

以片状锌粉和片状铝粉为原材料制备不同铝的质量分数的达克罗涂层。通过盐雾试验和电化学方法评价涂层的耐蚀性。结果表明:随着铝的质量分数的增加,达克罗涂层逐渐变得光亮、细致、光滑;涂层的自腐蚀电位依次升高,铝的质量分数50%以上的涂层,不具备牺牲阳极性能;涂层耐盐雾腐蚀时间的变化趋势与涂层牺牲阳极作用持续时间的变化趋势一致,均先升后降,在铝的质量分数为15%处达到极大值。

Dacromet coatings with different mass fraction of Al were prepared with zinc and aluminum flakes as raw materials, and the corrosion resistance of the coatings was evaluated and investigated by using salt spray test and electrochemical methods. The experimental results show that with the increasing of mass fraction of aluminum, Dacromet coating gradually becomes brighter and smoother; the selfcorrosion potential of the coating turns more positive sequentially, and coatings with mass fraction over-50 % of aluminum do not behave as sacrificial anode; the trend of corrosion resistance of the coating shown in salt spray test corresponds with the trend of sacrificial anode functioning duration of the coating. The common curves both rise up, and then fall down, and its maximum appears when mass fraction of aluminum is 15%.