摘要
在水杨酸钠溶液中采用循环伏安法在AZ31镁合金表面分别电聚合聚吡咯(PPy)膜和聚吡咯-钼酸根膜(PPy-MoO_4^(2-))。利用扫描电子显微镜(SEM)观测PPy膜和PPy-MoO_4^(2-)膜层腐蚀前后的表面形貌,衰减全反射红外光谱(ATR-IR)反映了PPy膜和PPy-MoO_4^(2-)膜的特征吸收峰,研究了MoO_4^(2-)的存在对PPy特征吸收峰的影响。使用四探针法测量薄膜的表面电阻;采用开路电位(OCP),电化学交流阻抗谱(EIS)和动电位极化曲线测试PPy膜和PPy-MoO_4^(2-)膜在3.5%Na Cl溶液中浸泡12 h后的耐腐蚀性能。结果显示,PPy-MoO_4^(2-)膜层更紧凑,PPy-MoO_4^(2-)膜层的腐蚀电流密度比PPy膜的低3个数量级。钼酸根的存在使得PPy-MoO_4^(2-)膜的表面电阻比PPy膜小,且PPy-MoO_4^(2-)膜的耐腐蚀性能较好。
The polypyrrole（PPy） coating and polypyrrole-molybdate（PPy-MoO4^2-） coating were electro-polymerized in sodium salicylate solution by cyclic voltammetry（CV） on the AZ31 Mg alloy surface.Surface morphology of PPy coating and PPy-MoO4^2-coating on Mg alloy surface before and after being corrupted was observed by scanning electron microscopy（SEM）.Attenuated total reflection-infrared（ATR-IR） spectra showed the characteristic ring stretching peaks of the PPy coating and PPy-MoO4^2-coating,and also revealed the influence of MoO4^2-on the characteristic ring stretching peaks on PPy.The surface resistance was measured by four-point probe method.The open circuit potential（OCP）,electrochemical impedance spectroscopy（EIS） and potentiodynamic polarization analyzed the corrosion resistance performance of PPy coating and PPy-MoO4^2-coating on the Mg alloy surface in 3.5% Na Cl solution immersing for 12 h.The results show that the surface morphology of PPy-MoO4^2-coating is compact.And the corrosion current density of PPy-MoO4^2-coating is lower three orders than that of the PPy coating.The PPy-MoO4^2-coating on the Mg alloy surface has better corrosion resistance and smaller surface resistance than the PPy coating because of the existence of the molybdate ion.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2017年第6期1480-1485,共6页
Rare Metal Materials and Engineering
基金
National Natural Science Foundation of China(51305090,51479037)
Natural Science Foundation of Heilongjiang(B201317)
关键词
聚吡咯-钼酸盐
循环伏安
镁合金
腐蚀性
polypyrrole-molybdate
cyclic voltammetry
magnesium alloy
corrosion
