用丝束电极研究模拟碳化混凝土孔隙液中缓蚀剂对碳钢局部腐蚀的抑制行为

《用丝束电极研究模拟碳化混凝土孔隙液中缓蚀剂对碳钢局部腐蚀的抑制行为》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、物理化学学~(WuliHuaxueXuebao1JanuaryActa尸．一Chim．Sin．，2011，27(1)：127—134127[Article]、^，、^，、V．whxb．pku．edu．Crl用丝束电极研究模拟碳化混凝土孑L隙液中缓蚀剂对碳钢局部腐蚀的『】制行为董泽华石维郭兴蓬(华中科技大学化学与化工学院，武汉430074)摘要：应用丝束电极(WBE)的电位／电流扫描技术，研究了含Cr的模拟碳化混凝土孔隙液中，Q345B碳钢局部腐蚀在窄间和时间上的发生和发展特征，同时比较了四乙烯五胺(TEPA)和亚硝酸钠缓蚀剂对局部腐蚀抑

2、制能力的差异．结果表明NO；离子能快速渗透腐蚀产物层，并抑制锈层下的碳钢活性溶解，而乙烯胺由于在锈蚀层内的扩散速率低，初期反而会促进锈层下的局部腐蚀，随着烯胺分子扩散并吸附于锈蚀层，金属界面处，碳钢活性溶解才受到抑制．电化学阻抗谱(EIS)可反映局部腐蚀的萌发，但难以表征缓蚀剂在碳钢表面的不均匀吸附特征．基于丝束电极表面电位／电流分布所提出的局部腐蚀因子(LF)，可定量表征腐蚀的不均匀特征以及缓蚀剂对局部腐蚀的修复能力．关键词：丝束电极：碳化混凝土孔隙液：局部腐蚀：局部腐蚀因子：缓蚀剂中图分类号：0646；TG174．42Localiz

3、edCorrosionInhibitionofCarbonSteelinCarbonatedConcretePoreSolutionsUsingWireBeamElectrodesDONGZe—HuaSHIWeiGUOXing—PengfSchoolofChemistryandChemicalEngineering,HuazhongUniversityofScienceandTechnology,Wuhan430074R．China)Abstract：Theinitiation，growth，andtemporaIandspatiaId

4、istributionofIocalizedcorrosionofQ345BcarbonsteeIincarbonatedconcreteporesolutions(pH9．6)containing0．1mol·LCrionswereinvestigatedusingapotentialandgalvanicmappingtechniquebasedonawirebeamelectrode(WBE)．Diferentmechanismsforrepairandsuppressiononthestablelocalizedcorrosio

5、nbytetraethylenepentaminefTEPA)andnitritewerecompared．TheresultsjndicatethatnitritecanjnhibittheactivedissolutionofsteeIbeneaththerustlayerbecauseofthefastpenetrationofnitriteintotherustlayer~However．TEPAcanpromoteactivedissolutionundertherustIayerinitiallybecauseofitssl

6、owpenetrationratethroughtherustlayer．ThelocalizedactivedissolutionwasonlyrefrainedafteraIongtimebecauseofTEPAmoleculespermeatingintotheinterfacebetweentherustlayerandthesteelmatrix．Electrochemicalimpedancespectroscopy(EIS)wasusefulinallowingustodeterminehowtheIocalizedco

7、rrosionwasinitiatedbutfailedtoindicatetheheterOgeneOusadsorptionoftheinhibitorsonsteeI．AnewIocalizedcorrosionfactor(LF)basedongalvanicmappingisproposedandisshowntobeeffectiveforthecharacterizationoftheIocalizationofcorrosionandtheinhibitioneffectofinhibitorsonIocalizedco

8、rrosion．KeyWords：Wirebeamelectrode；Carbonatedconcreteporesolution；LocalizedcorrosionLocalizedcorrosionf