NMZ1耐磨铸钢在模拟海水中的电化学腐蚀行为  

Electrochemical Corrosion Behavior of NMZ1 Wear-resistant Cast Steel in Simulated Seawater

作　　者：周祺[1,2] 马爱斌[1,2,3] 江静华[1,2,3] 杨东辉[1] 陈建清[1] 卢富敏[1] 邹中秋[2] 曹晶晶[1] 

机构地区：[1]河海大学力学与材料学院,南京210098 [2]河海大学水资源高效利用与工程安全国家工程研究中心,南京210098 [3]常州市河海科技研究院有限公司,常州213164

出　　处：《腐蚀与防护》2011年第9期677-680,共4页Corrosion & Protection

基　　金：国家"十一五"科技支撑计划重大项目(2006BAA01A24-3);常州市工业科技成果转化及产业化计划项目(CC20100004)

摘　　要：测试了NMZ1低碳高强耐磨铸钢在3.5%NaCl溶液中的极化曲线和电化学阻抗谱(EIS),结合腐蚀形貌观察分析了其电化学腐蚀机理,并以优质系泊链钢(22MnCrNiMo)为参照,评价了该新型海洋用钢的耐蚀性。结果表明,腐蚀初期NMZ1钢的耐蚀性不如系泊链钢,其分级淬火后组织中的残余奥氏体和下贝氏体诱发了选择性腐蚀,因而腐蚀速率较高(腐蚀电流密度为0.674 mA/cm^2,电荷迁移电阻值为265Ω/cm^2);浸泡至腐蚀稳态阶段,由于NMZ1钢表面形成了均匀的保护性腐蚀产物膜,其腐蚀电流密度和电荷迁移电阻均与系泊链钢接近。该新型钢种综合性能良好,有望在海洋工程领域推广使用。The corrosion resistance of NMZ1 wear-resistant cast steel was compared with that of the mooring chain steel （22MnCrNiMo） by observing the corrosion morphology and measuring the Tafel linear sweep and electrochemical impedance spectroscopy （EIS） in 3. 5% NaCl solution to reveal the electrochemical corrosion mechanism. The results showed that the corrosion resistance of the NMZ1 steel was worse than the mooring chain steel at the initial stage of soaking, the corrosion current density and the charge transfer resistance of the NMZ1 steel were 0. 674 mA/cm^2 and 265 Ω/cm^2 , respectively. The higher corrosion rate of the NMZ1 steel was due to the selective corrosion caused by the retained austenite and lower bainites existing in the microstructure. The corrosion current density and the charge transfer resistance of the NMZ1 steel were close to those of the mooring chain steel at the corrosion steady stage because of the protection of the compact corrosion product scale on the surface. It is hopeful to be widely used in marine engineering fields owing to the good comprehensive properties of the NMZ1 steel.

关 键 词：耐磨铸钢 海洋用钢 电化学腐蚀 耐蚀性 

分 类 号：TG172.5[金属学及工艺—金属表面处理]