风电用环氧玻璃鳞片涂层防腐性能的电化学研究
|
摘要
通过分析环氧玻璃鳞片涂层的电化学交流阻抗谱(EIS)、电阻电容和特征频率的变化特点,对其在各个浸泡阶段的防护机理进行了研究.结果表明:在浸泡初期,环氧玻璃鳞片涂层良好的屏蔽作用可阻挡水分子和腐蚀介质的渗入;在浸泡中期,环氧玻璃鳞片涂层因吸水饱和而失效,导致腐蚀介质渗透到钢铁基材表面,发生电化学反应而引起腐蚀,但是,由于腐蚀产物添堵了孔隙,再加上玻璃鳞片的层状分布使腐蚀介质渗入得以延缓,从而使腐蚀速率降低;在浸泡后期,环氧玻璃鳞片涂层快速失效,腐蚀产物大幅增加导致膨胀剥落,腐蚀介质直接和钢铁基材发生电化学反应,防护能力极低.
Through the analysis of the electrochemical impedance spectroscopy(EIS),the resistance capacitance and the characteristic frequency of the epoxy glass flake coating,the protective mechanism were studied.Results show that in the early stage of immersion,the epoxy glass flake coating has good shielding effect,which can prevent the infiltration of water molecules and the corrosive medium;in the immersion medium,epoxy glass flake coating fails due to water saturation,resulting in corrosion spread into the steel substrate surface,electrochemical reaction and corrosion,but because the corrosion product fills pores and layered glass flake corrosion medium makes in-depth growth path,which effectively lowers the corrosion rate of coating;in the late period of immersion,the epoxy glass flake coating is quickly ineffective,and the increase of the corrosion product causes the expansion of the coating.The corrosive medium directly has an electrochemical reaction with the metal substrate,the coating is completely ineffective,and the protection ability becomes very poor.
Through the analysis of the electrochemical impedance spectroscopy(EIS),the resistance capacitance and the characteristic frequency of the epoxy glass flake coating,the protective mechanism were studied.Results show that in the early stage of immersion,the epoxy glass flake coating has good shielding effect,which can prevent the infiltration of water molecules and the corrosive medium;in the immersion medium,epoxy glass flake coating fails due to water saturation,resulting in corrosion spread into the steel substrate surface,electrochemical reaction and corrosion,but because the corrosion product fills pores and layered glass flake corrosion medium makes in-depth growth path,which effectively lowers the corrosion rate of coating;in the late period of immersion,the epoxy glass flake coating is quickly ineffective,and the increase of the corrosion product causes the expansion of the coating.The corrosive medium directly has an electrochemical reaction with the metal substrate,the coating is completely ineffective,and the protection ability becomes very poor.
引文
[1]GONZLEZ-GUZMN J,SANTANA J J,GONZLEZ S,et al.Resistance of metallic substrates protected by an organic coating containing glass flakes[J].Progress in Organic Coatings,2010,68(3):240-243.
[2]HATTORI M,NISHIKATA A,TSURU T,et al.Influence of residual rust on underlying steel surface on performance of heavy-duty coating[J].Zairyo-to-Kankyo,2011,60(1):15-21.
[3]颜小东,高敬民,王云普,等.用电化学阻抗谱(EIS)最大相角频率(fθmax)法快速评价风电涂料[J].现代涂料与涂装,2010,13(6):30-33.YAN Xiaodong,GAO Jingmin,WANG Yunpu,et al.Rapid test method of evaluating the wind power coatings by using the frequency at the maximum phase angle of EIS[J].Modern Paint and Finishing,2010,13(6):30-33.(in Chinese)
[4]张延丰.玻璃鳞片技术参数的选择及表面处理的作用[J].腐蚀与防护,2000,21(12):550-552.ZHANG Yanfeng.Influence of technological parameters of flake glass on the coating's characteristics[J].Corrosion and Protection,2000,21(12):550-552.(in Chinese)
[5]张基沛.玻璃鳞片涂料的重防腐蚀作用[J].腐蚀与防护,2003,24(9):401-402.ZHANG Jipei.Application of glass-flake-doped coatings to long-term anti-corrosion[J].Corrosion and Protection,2003,24(9):401-402.(in Chinese)
[6]曹楚南,张鉴清.电化学阻抗谱导论[M].北京:北京科学出版社,2002:219.CAO Chu'nan,ZHANG Jianqing.An introduction to electrochemical impedance spectroscopy[M].Beijing:Beijing Science Press,2002:219.(in Chinese)
[7]曹楚南.腐蚀电化学原理[M].北京:化学工业出版社,2004:217-224.CAO Chu'nan.Principles of electrochemistry of corrosion[M].Beijing:Chemical Industry Press,2004:217-224.(in Chinese)
[8]HIRAYAMA R,HARUYAMA S.Electrochemical impedance for degraded coated steel having pores[J].Corrosion,1991,47(12):952-958.
[2]HATTORI M,NISHIKATA A,TSURU T,et al.Influence of residual rust on underlying steel surface on performance of heavy-duty coating[J].Zairyo-to-Kankyo,2011,60(1):15-21.
[3]颜小东,高敬民,王云普,等.用电化学阻抗谱(EIS)最大相角频率(fθmax)法快速评价风电涂料[J].现代涂料与涂装,2010,13(6):30-33.YAN Xiaodong,GAO Jingmin,WANG Yunpu,et al.Rapid test method of evaluating the wind power coatings by using the frequency at the maximum phase angle of EIS[J].Modern Paint and Finishing,2010,13(6):30-33.(in Chinese)
[4]张延丰.玻璃鳞片技术参数的选择及表面处理的作用[J].腐蚀与防护,2000,21(12):550-552.ZHANG Yanfeng.Influence of technological parameters of flake glass on the coating's characteristics[J].Corrosion and Protection,2000,21(12):550-552.(in Chinese)
[5]张基沛.玻璃鳞片涂料的重防腐蚀作用[J].腐蚀与防护,2003,24(9):401-402.ZHANG Jipei.Application of glass-flake-doped coatings to long-term anti-corrosion[J].Corrosion and Protection,2003,24(9):401-402.(in Chinese)
[6]曹楚南,张鉴清.电化学阻抗谱导论[M].北京:北京科学出版社,2002:219.CAO Chu'nan,ZHANG Jianqing.An introduction to electrochemical impedance spectroscopy[M].Beijing:Beijing Science Press,2002:219.(in Chinese)
[7]曹楚南.腐蚀电化学原理[M].北京:化学工业出版社,2004:217-224.CAO Chu'nan.Principles of electrochemistry of corrosion[M].Beijing:Chemical Industry Press,2004:217-224.(in Chinese)
[8]HIRAYAMA R,HARUYAMA S.Electrochemical impedance for degraded coated steel having pores[J].Corrosion,1991,47(12):952-958.